第 118 期·中文精讀

格蘭特·桑德森:數學、Manim、神經網路與 3Blue1Brown 的教學之道

Grant Sanderson: Math, Manim, Neural Networks & Teaching with 3Blue1Brown

以動畫講解數學的創作者談 Manim 工具的由來、神經網路視覺化,以及如何把抽象概念講清楚。

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中文精讀由 AI 基於原始訪談改寫,非官方翻譯,可能存在偏差或錯誤;表述以原音訊與官方文稿為準。說明

在咖啡館裡,格蘭特·桑德森(Grant Sanderson)正捧著一本關於費曼的書。一個陌生女人瞥了一眼封面,湊過來說:哦,費曼,我愛他,我讀過《別鬧了,費曼先生》。然後她開始解釋,費曼其實從來不算是個“數學型的人”。

格蘭特當時坐那兒有點懵。一個物理學家,被公眾認知成“跟數學沒什麼關係”,這事怎麼想都彆扭。但更彆扭的是,這句話反過來倒像是一種讚美:在很多人心裡,費曼的偉大恰恰在於他“繞開了”數學,用最直白的方式觸碰到了真實世界。

這是格蘭特第二次上 Lex Fridman 的播客。他做 YouTube 頻道 3Blue1Brown,做數學視覺化,做了 Manim 這個動畫引擎。兩個多小時裡,話題從費曼聊到拓撲學,從指數增長聊到 GPT-3,從貝爾實驗室聊到神經元網路,中間穿插了不少關於創作、孤獨和教育的自我剖白。

如果你只想知道結論,大概有這麼幾條:讓人爽的內容不等於讓人記住的內容;最有資格講某件事的人,往往最不敢點發布;萬物理論是塊太大的肉,啃不動;而人這一生最大的遺憾,可能是沒和同事共用過一間辦公室。

咖啡館裡那句話,把費曼說成了“不算數學型的人”

格蘭特對費曼的興趣不在那些段子。讓他真正記住費曼的,是一封信。

那是費曼寫給妻子的信,寫在妻子去世兩年之後。她在曼哈頓計劃期間得了脊髓灰質炎,很年輕就走了,兩個人當時正愛得不可開交。信裡費曼說,他有多愛她,沒有任何女人能和她比。

你在《別鬧了,費曼先生》裡看到的那個費曼,和現實裡的費曼是兩個人。(格蘭特·桑德森)

公眾印象裡的費曼,有點像個油嘴滑舌、略帶性別歧視的花花公子。可那封信是完全另一個人寫的。格蘭特說,這跟費曼在科學上的形象也有點像:表面上他是那個拍著桌子說“你們別搞那些花裡胡哨的公式,我就要最本質的東西”的傢伙,看著特別接地氣,特別反理論。可他真正在做的事,深得很,數學密度極高。

那句“他從來不是個數學型的人”之所以能流傳,大概是因為觀眾太想相信這個故事了。我們想相信,偉大可以繞開枯燥的技術細節,靠直覺和天分直接抵達真相。這種敘事聽著舒服,但它不真。

費曼身上另有一件事讓格蘭特著迷:他讀論文的方式是先自己解一遍。看到一個別人提的問題,他會先試著從零開始想,建立起自己的手感,然後才去看別人是怎麼做的。

格蘭特很認同這一點,也承認這方法極其拖慢進度。他自己不是活躍的研究者,某種程度上就是因為這個:學東西太慢。但他也由此得到了一些別人不會有的東西,那些說不清道不明、但真實存在的直覺。因為你自己試過,所以你會去構造反例,會去想象邊界情況,會在大腦裡堆積一堆屬於自己的資料和例子,而不是作者給你的那些。

如果你只是順著證明讀一遍,那些直覺是不會長出來的。(格蘭特·桑德森)

費曼效應:讓你爽的,不等於讓你記住的

但費曼也有一個“坑”。

教育界有個說法叫費曼效應:你看他講課、讀他的講義時,一切都順得像水,那種“我終於懂了”的快感,別處真找不到。可是一週之後,你回想不起來到底是什麼讓你產生了那種感覺。

格蘭特說,這個風險對他自己的影片同樣成立。他做的東西,最理想也就是一份“智力糖果”,給人一次“好像懂了”的幻覺。想要真的留住,必須自己動手:重新推一遍,做題,用間隔重複把術語的磚塊壘住。否則什麼都留不下。

讓費曼講座如此令人享受的那個東西,可能恰恰也是我們作為教育者應該警惕的那個缺陷:它和長期學習並不成正比。(格蘭特·桑德森)

對自己這份工作,他做過最清醒的一次審視就在這兒。他不否認影片的價值,但他清楚那條線畫在哪兒。

狐狸和刺蝟:他為什麼不去鑽同一個洞

有人問他,你遊過那麼多領域,懂得那麼深,有沒有想過扎進去,發現點新東西?

格蘭特提到一個老比喻:狐狸知道很多事,刺蝟只知道一件,但知道得極深。馮·諾依曼是狐狸,愛因斯坦更接近刺蝟。兩種人都推進了科學。

他把自己歸到狐狸那一類,還說了一句很實的話:他現在什麼都知道得不夠多,不足以在任何領域做出有分量的貢獻。他最大的本科遺憾是沒和教授們建立好關係,因為他覺得科研的成功很大程度上靠師徒制,靠有人給你遞上一層層墊腳的問題。

但狐狸有一個產出:講解上的新貢獻。有些東西是“已知的,但沒被講清楚”,這就留出了空間。他說,如果自己未來能做出點什麼,大機率是在這一類。

這也解釋了為什麼兩個相鄰的數學分支,可以彼此聽不懂對方在說什麼。把做複分析的和做代數幾何的博士生放進彼此的討論班,兩邊都像你我一樣懵。所以,一個願意在好幾個山頭之間來回走、試著把大圖景連起來的人,本身是有價值的。

數學要麼平凡,要麼不可能,以及拓撲學被講壞的方式

Lex 說,跟格蘭特聊天有個感受:機器學習裡兩週你就覺得自己“基本掌握”,數學裡則是另一種節奏。

格蘭特的回答很精準:在數學裡,一個東西要麼平凡,要麼不可能,中間那條線薄得驚人。你剛接觸一個主題時它完全不可穿透,等你有點感覺了,回頭看又覺得“整個主題其實挺平凡”。所以每個研究者其實都站在那道坎的另一側,你從外面看覺得遙不可及,走上一步其實就到了。

聊到教學,他把矛頭指向了拓撲學的科普方式。

你可能聽過那種經典說法:拓撲學家關心的是“可以扭曲拉伸,但不能剪開也不能粘合”的形狀。這個說法很可愛,甜甜圈和馬克杯,但格蘭特說它根本沒講到點子上。

難道真有數學家坐那兒想,我想研究一下黏土的性質?不是的。(格蘭特·桑德森)

拓撲學真正的動機是:有一大堆數學物件,它們共享某種“幾何但沒有精確距離、只有遠近概念”的結構。你把這些結構抽象出來,就能在不同數學分支之間建立對映,翻譯成非平凡的事實。這才是數學家真正在做的事,但它很少被講出來。

學習者因此陷入兩難:要麼聽了一堆咖啡杯和甜甜圈,覺得“這也太軟了”;要麼一上來撞見開集公理,發現“開集不是閉集的反義詞”,覺得“這也太硬了”。中間那段真正有意思的路,被跳過去了。

他自己拍過一支莫比烏斯環的影片,就是想補這段路:你想把一個莫比烏斯帶的邊界剛好放在平面上,同時整個帶子都在平面之上,直覺告訴你不可能不自我相交,但你沒法說清為什麼。要去說清,你就得開始定義“可定向”和“不可定向”,而一旦有了這個動機,拓撲學教材開頭那一堆看起來隨意的定義,忽然就有了來由。

我們對指數的直覺,是被訓練掉的

很多人以為自己不懂指數增長。格蘭特的看法相反:人類天生對指數極其敏感,是後來的教育把它訓練掉了。

他舉了一個人類學觀察。在一些還沒有系統算術的社會里,問“1 到 9 之間是幾”,人們的第一反應往往是 3。因為 3 在幾何意義上位於中間:1 乘 3 得 3,3 乘 3 得 9。同理,1 個朋友和 100 個朋友之間“中間是什麼”,答案是 10 個朋友,那才是社會地位上的中點。

我們天生就是用對數思考的,然後被基礎算術訓練成了線性思維。(格蘭特·桑德森)

但真正反直覺的部分,在大數那一端。你讓一個沒有算術的社會去算“1 顆石頭連翻三倍七次是多少”,答案也會讓他們吃驚。這意味著:小數段的指數直覺我們天生就有,大數段的指數直覺需要靠訓練補上。

米粒、睡蓮,和“倒數第二天”

他講了兩個經典例子。

一個是棋盤上的米粒。國王答應給一份賞賜,對方說只要在棋盤第一格放 1 粒米,第二格 2 粒,第三格 4 粒,一直翻倍到第 64 格。最後一格需要的米粒,超過全世界所有米的總和。

另一個是湖面上的睡蓮。一片睡蓮每天翻倍,第 50 天鋪滿整個湖。問:第幾天鋪滿一半?第 49 天。

Lex 聽到這兒停了一下,說“我下意識覺得這不可能”。格蘭特說這一下正好證明了問題。你知道了規則,算之前還得先愣一下,這就是我們的直覺塌陷的地方。

他還有一個更狠的版本:不要問“第幾天鋪滿一半”,改問“第幾天鋪滿百分之一”。答案是第 43 或 44 天左右,需要翻 6.5 次。也就是說,在 50 天裡的第 44 天,你還在看著 1% 的湖面,然後一轉眼,整個湖都是了。

你已經在 50 天裡的第 44 天了,而這個睡蓮才鋪了 1% 的湖面。下一秒,整個湖就是它了。(格蘭特·桑德森)

這個改法比“一半”那個版本更狠的地方在於,它對應的是真實世界裡疫情早期的心理狀態:資料看著還挺溫和,然後忽然就不是了。

摩爾定律算不上指數增長

Lex 提到馬斯克喜歡講指數思維,喜歡說“大家以為不可能的事,因為指數就變成了可能”。

格蘭特的回應分兩層。第一層,1960 年代認真對待摩爾定律的那批人,確實預言了個人電腦、智慧手機這些東西,那種“相信”本身產生了作用。

第二層更有意思。嚴格來說,摩爾定律算不上“指數增長”,它更像一個被設定出來、然後所有人被逼著去達成的基準。真正的指數增長要求變化率正比於自身,就像軟體讓你能寫出更多軟體。而摩爾定律更像“四分鐘一英里”:一旦有人證明這事可行,這件事就變成了全行業的壓力,一堆微創新被擠出來,把曲線硬頂著走。

摩爾定律更像全行業被逼著去達成的一個目標,睡蓮自己在那兒長這種解釋,套不到它頭上。(格蘭特·桑德森)

所以真正值得問的問題在於:什麼時候變化率真的正比於自身,這條曲線畫成什麼樣反而是次要的。只有搞清楚機制,你才能判斷它什麼時候會斷。疫情是反過來的版本:你希望傳播越快越好的是思想,而病毒恰恰是你不希望它遵循這個機制的。

孤獨,是格蘭特最想改掉的東西

聊到曼哈頓計劃和貝爾實驗室,Lex 問了一句:你一個人做這些,孤獨嗎?

整場對話裡,格蘭特最坦率的地方在這兒。

說實話,那是我人生裡最想改變的部分。我看著貝爾實驗室那種狀態,心裡想,天哪,我太羨慕了。(格蘭特·桑德森)

他讀費曼的傳記,發現費曼和施溫格(Julian Schwinger)共用一間辦公室,脫口而出“那當然了,他們當然共用辦公室,想法就是這麼長出來的”。雖然這兩人實際上大機率是各幹各的,但那種“你去拿個零食的路上撞見人”的魔法是真的。

他自己有一點點這種環境,因為他刻意保持和一些思維方式相近的人的聯絡。但這不是日常,不是每一天都在發生。

Lex 提到他弟弟的日程表上有一項,標題就叫“沒有具體議程”。兩人都覺得這是個好辦法,等於人為製造偶遇。我們平時在酒吧、在火車上碰到的陌生人,那種隨機的對話,是被遠端辦公悄悄拿掉的東西。

關於“一個人工作”,格蘭特還有一句很有意思的話:他其實更喜歡獨自工作。這是性格上的怪癖。但他也承認,那種“這個太長、這個太短、這個視覺化爛透了”的自我懷疑,對自己說比對合作者說容易得多。所以他會很輕易地扔掉一版指令碼,卻很難開口讓別人也扔掉。

寫作是最難的部分,所以第一件事是拔網線

格蘭特的工作有四種模式:研究、寫指令碼、動畫程式設計、處理郵件。他明確說,最難熬的是寫指令碼。

他理想中的一個高效寫作日是這樣的:早起,鍛鍊,然後把網線拔掉。想查的東西先記在便籤上,等允許上網的時候再查。寫不下去的時候,解決寫作卡殼的辦法是去讀點東西,甚至不用相關,讀個十五到三十分鐘,再回來繼續寫。

但他也承認自己不是個系統性的人,不打卡、不數小時。Lex 提到卡爾·紐波特(Cal Newport)的深度工作法,格蘭特說,那些“完美的一天”的日程表,寫出來比執行起來好玩得多,而且寫的時候你寫的是最好的自己,你不會寫“我今天想賴床但又不得不起”這種細節。

寫作這件事上,他有一條很明確的建議:不要先立專案再去學。

更糟的做法是:我要開始做這個影片了,所以我現在開始研究。更好的做法是平時在背景裡廣泛地學,等某一天你感覺“這個我懂了”,再把它放進“可以做影片”的清單裡。(格蘭特·桑德森)

先立專案再學,結果只有兩種:要麼卡死,要麼講不好。

他還提到一個判斷標準:如果一個題目沒有一個“啊哈”的瞬間能把整個故事串起來,就不該開工。他有一大袋子這種時刻,隨時可以掏出來用。

評論區的人,代表不了觀眾的大多數

聊到創作心理,格蘭特說了一句可以做所有內容創作者座右銘的話。

評論的公眾,不代表真實的公眾。(格蘭特·桑德森)

你自己想想,你多久看一次 YouTube 評論?大多數人會意識到:我從來不看。那些意識到自己從來不看的人,應該反過來推一下:和你一樣的人,也不會去留評論。

所以評論區是嚴重有偏的樣本。覺得無聊的人不會看完,更不會留言;只有特別愛你的人,或者特別憤怒的人,才會花時間打字。前者讓你高估自己,後者讓你懷疑人生。

格蘭特說他自己如果只看評論,會以為自己的內容比實際更好,因為留言的人都太友善了。而那些真正被打動的、他真正想觸達的觀眾,通常什麼都沒寫。

他還講了個段子。他媽媽早年每天手動把頻道里所有影片的播放量加起來,然後發簡訊告訴他“頻道現在有 990,000 次觀看了”,她以為自己在給他提供一份別處看不到的“全域性分析”。

Lex 提到喬·羅根(Joe Rogan)不讀評論,而且不是假裝不讀,是真的不在乎。兩人都覺得,這種狀態在今天挺稀缺。你聽那些善意觀眾的代價,是你的心理被網際網路底層的毒性一點點侵蝕,這兩筆賬,其實記在一起。

格蘭特自己的做法是:發內容的時候順便看一眼前一天的,一天一次,90% 的日子能做到。然後每兩週會有一次破功,刷到停不下來。

直播課、OBS,和“商品化的講解”

疫情期間他做了一系列直播課,叫“Lockdown Math”。這對他來說幾乎是反向操作:出鏡、實時、不能剪。

他做這個的動機很直接:他平時出片太慢,幫不上當時那些在家找學習資源的人。那就乾脆雙週一次直播,學生知道什麼時候來,老師知道往哪兒指。

技術上他說得很細。他之前完全不懂這些,是一個朋友帶的。核心是用 OBS 這類直播軟體,而不是直接螢幕共享:你可以預設好幾個場景(對著臉、俯拍紙面、演示 Desmos),然後用鍵盤快捷鍵切換。以前需要一個導播團隊喊“切三號機”,現在一個人就能幹。練一練,偶爾出錯,但整體可以很順。

他為此寫了一篇部落格,講自己的裝置佈置,以及怎麼把 OBS 和 Zoom 整合起來。

這次疫情裡,教育上可能發生的最好的一件事,是把一大批老師訓練成了內容創作者。(格蘭特·桑德森)

他有個說法叫“商品化的講解”。一個代數一的知識點,全世界每年被不同老師講幾百萬遍,這非常低效。理想狀態是:網際網路上存在那麼幾份最好的講解,誰需要誰去看;課堂時間則用來做講解之外的事,而那才是教學的大部分。

要走到那一步,就得讓已經在講課的人把講解公開出來。疫情逼著所有人上線,如果這個上線成了“一件本來就要給更多人看的東西”,而非一場恰好被錄下來的 Zoom 會議,那就值了。

他還給了一個非常實用的建議:一個老師一年只挑一個自己最懂的主題,做出這個世界上關於它的最好的一支講解影片。就一個。所有好老師都這麼做,網際網路上就什麼都有了。

這件事還有自利的一面。對學者來說,這相當於在《自然》上發一篇所有人都能讀的 letter,你畢生的熱愛會被遠超預期的人看見。而且,是這些影片在告訴年輕學生該對什麼感興趣。想讓系裡招到更好的研究生?做出你能做的最好的影片,等八年。

最有資格講的人,往往最不敢點發布

裝置這塊他說得很樸素。旁白用 USB 麥克風,Blue Yeti;直播用領夾麥,大機率是 Røde 的。至於音訊難不難搞,他說去聽自己頻道早期的影片就知道了,很長一段時間他都搞不定,“你聽自己的聲音會覺得怪,分不清是你不習慣,還是真的有音訊瑕疵”。

直播用的是兩到五臺相機,一臺俯拍紙面,一臺對著臉。俯拍那臺也可以換成 iPad 電子書寫,但他想要紙張的質感。相機輸出會經過壓縮再進電腦。

Lex 提到 MIT 的機器人教授拉斯·泰德拉克(Russ Tedrake),講欠驅動機器人,課很受歡迎,也在玩 Manim,還專門來問該買什麼裝置。格蘭特笑著說:我不推薦我這一套,太貴也太難搞。

更重要的那段在後面。Lex 說,他父親是等離子體物理的好老師,能把很複雜的東西講得很簡單,可你去搜等離子體物理,幾乎沒有影片。那麼多好老師,哪怕一年只做一個,網際網路也會比現在豐富得多。

格蘭特接過話,說真正的障礙跟技術無關,是怕丟人。

我真希望那些會說“我憑什麼來講這個”的人,才是真正去發影片的人。(格蘭特·桑德森)

真實情況有點殘酷。現在的教育內容裡,有相當一部分是兩週前才開始學的人在做,節奏還被演算法推著走。真正該講的人,因為有自知之明,反而閉嘴了。

他說這也是為什麼那些在紙上講數學的頻道(numberphile 一類)有價值:把一個極聰明的人按在那兒,逼他對著一張紙講清楚。但一個頻道做不成規模,得靠每個領域的行家自己動手。

而且現在正是時候。你反正在做線上內容了,就按一下那個釋出鍵,看看會怎樣。

YouTube 有個好處:它可能很久都沒動靜,但十年之後還在那兒。(格蘭特·桑德森)

不過這份“永久”也得打個折扣。Lex 提到喬·羅根把整個長影片庫從 YouTube 撤走搬到 Spotify,那一刻他才第一次意識到,YouTube 上的東西未必會一直在。格蘭特說他自己也想過這個:快進五十年,Alphabet 可能已經不是當年那個公司了,那些沒人看的影片伺服器成本很高,說不定哪天就開始清理。

要是五十年後人們根本不用 YouTube 了呢,他們在看別的東西,這好像挺可能的。(格蘭特·桑德森)

他甚至提了一個技術上的解法:內容定址(content addressing)系統,地址直接指向內容本身,只要網路上還有一個人託管,它就永遠在那個地址上可訪問。但他也承認,這改變不了一個事實:如果人們不再習慣去那兒,連結再穩也沒意義。想到這兒他還是有點難過,因為那本來會是一片可以永遠回去的、關於每個主題的經典影片集合。

神經網路的迷人之處:自動的抽象

聊到深度學習,格蘭特說最讓他著迷的是分層結構。

每一層乾的活看起來性質完全不同:靠近輸入的那幾層抓紋理、邊緣這種極低層的東西,越往後越抽象,開始識別“眼睛在哪”“這個眼睛組成了什麼動物”“是貓還是狗”。但每一層遵循的數學規則是一樣的:一個非線性,加一個矩陣乘法。

一臺通用的機器,層層跑過抽象,而抽象在某種意義上構成了智慧。(格蘭特·桑德森)

他管這個叫“自動化的抽象”。這一點他覺得非常有力量。你看克里斯·奧拉(Chris Olah)那些對卷積網路的經典視覺化:問一個神經元在做什麼,問一組神經元在做什麼,答案是一層層往上升的語義。同一塊數學,長出了完全不同的東西。

當然他也自嘲,深度學習的研究風格有點像“先做一堆臨時試驗,再看哪個靈,然後回頭補一個數學解釋,說它本來就該 work”。不過他說,只要最後能拿到那個漂亮的數學,怎麼走到的其實無所謂。

為什麼這麼“笨”的梯度下降能 work

Lex 提到一個常見感慨:神經網路要最佳化的那個曲面,到處都是區域性極小值,可這麼蠢的梯度下降居然能找到好解,太反直覺了。

格蘭特給了兩層回答。

第一層,他不太驚訝。引數空間維度那麼高(GPT-3 有 1750 億個引數),裡面當然到處都是“好解”,最優解未必有,但足夠好的解無窮多。真正值得問的是效率:怎麼能這麼快地碰到一個。

第二層是真正的答案。梯度下降在神經網路上好用,而在任意引數化上都好用不了,靠的是分層結構讓導數的分解在計算上可行,也就是反向傳播。這才是那個“魔法”的來源。

這跟斯蒂芬·沃爾夫勒姆(Stephen Wolfram)的一個觀察呼應:如果你把所有可能的計算空間鋪開,會驚訝於其中“有意思”的比例有多高。我們習慣性以為智慧是極小的一撮,其實有意思的計算多得是。

但真正難的問題在於:哪些有意思的東西可以用極低的資訊量描述出來。因為只有這樣,你才能把它寫出來、建出來、工程化。

夏農、隨機編碼,和低資訊量的描述

他舉了夏農(Claude Shannon)的噪聲通道編碼定理作為例子。

你要給對面發一串位元,中間有噪聲,會有位翻轉。你想找到一種編碼方式,能抗住噪聲。夏農證明這種好編碼存在的方式非常奇特:他不構造,甚至不做常規意義上的非構造性證明,他說的是隨便隨機選一個編碼,它幾乎就貼著理論極限。

聽起來很爽。但後果是:之後幾十年,沒人真的找到接近極限的編碼方式。

因為“隨機選一個”和“高效地把它寫出來”是兩件完全不同的事。那個隨機選出來的編碼,你要真實現它,就得有一張巨大的查詢表告訴你每一位怎麼對映,這在計算上根本不可行。

有時候,從一個巨大到離譜的集合裡隨機取一個元素,和找到一種高效描述它的方式,完全是兩回事。(格蘭特·桑德森)

這就是他眼裡真正難的問題:怎麼讓一個東西既有極低的資訊量描述,又能表現得足夠有意思。這個問題解決了,才談得上工程化。順帶一提,這也正好解釋了為什麼大量“可能存在的程式”毫無意義,真正稀缺的是那些用幾行方程就能寫出來、卻依然複雜到無法預測的東西。

GPT-3:喪屍末日,和它不會數數

聊到 GPT-3,格蘭特說前幾天剛收到一封郵件,有人想拿 GPT-3 配 Manim,給它一段高層描述,讓它自動生成數學動畫,“這是想讓我失業啊”。

他被逗樂的地方在於,他不太相信這東西能按描述的樣子工作,但承認如果挑對例子,能生成點酷東西出來已經足夠有價值。他打了個比方:寫作很多時候就是把一堆東西先倒在頁面上,再決定刪到剩什麼。如果 AI 能當那個生成器,人當那個篩選器,這種人機共生就挺強。

他最喜歡的 GPT-3 演示,是 Tim Blais(頻道 Acapella Science)發在推特上的。因為 GPT-3 訓練資料截止在疫情之前,所以它不知道新冠。Tim 給它餵了個開頭:一種新型病毒在中國武漢出現,開始向全球擴散。以下是一個月接一個月的記述,一月……

然後它寫出來的東西,會發展成一場喪屍末日,當然如此,因為它的訓練語料裡全是這種故事。但你看到的,是一個“如果新冠是喪屍末日”的版本,前幾段意外地還挺合理,然後迅速失控。

另一方面,它在數學上很弱。給它一串五位數,讓它找規律,它不行。斐波那契數列喂幾項,它很快就錯。

格蘭特解釋得挺細。人類看 1、1、2、3、5、8、13,不會只憑直覺猜下一個,而是腦子裡同時掛著好幾個假設,然後主動去檢驗:是不是由前兩項生成?是不是乘一個常數?你的直覺圍著這些假設轉,但你還是得去驗證。數學和別的領域的區別就在這兒:模式識別到不了終點,模式只是通往終點的路標。

1、2、4、8、16、31

他講了個例子,是他頻道早期的一支影片。在一個圓上取點,把每兩個點連起來,數圓被分成了幾個區域。

1 個點:1 個區域。2 個點:2 個。3 個點:4 個。4 個點:8 個。5 個點:16 個。

看到這兒,幾乎所有人都會說:2 的冪。這規律我們見過一百萬次了。

然後下一個是 31。

差不多是 2 的冪,但差了一點。而這個“差一點”背後有非常漂亮的解釋。

這挺能測試一個人,看你思考機制解釋的時候清不清楚,你有多快就跳到“一定是 2 的冪”。(格蘭特·桑德森)

真正成熟的數學家和初學者在這裡的差別,不在誰見的模式更多,而在看到模式的瞬間,會不會先去問“這個問題本身長什麼樣,它該不該產生這種模式”。

他說,如果真有一個演算法能主動做到這件事,他會非常佩服。那基本上就是個小科學家。

Python 最好和最糟的地方,都在同一件事上

話題切到 Manim 和 Python。他說自己一直對 Manim 有愧疚感,因為它是“一個數學老師拼湊出來的程式碼庫”,很多設計上的彆扭都源於他不是軟體工程師。他這一年花了些功夫改,也承認自己在社群維護上“羞愧地疏忽了”。

他給了個很實在的建議:先想清楚你要做的東西該不該用程式碼做。只是畫個函式圖,加點動效,那就用 Desmos、GeoGebra、Jupyter,或者 Mathematica。這些工具能把你帶得很遠,而且省事得多。他自己的影片裡有些部分,用現成工具其實更合理,但他因為要持續改進 Manim,就順手用自己的了。

照我說的做,別照我做的做。(格蘭特·桑德森)

他做 Manim 的原始動機,是不滿足於“函式只能畫成圖”。函式有很多種表示方式,其中一種是用時間上的運動來傳達輸入和輸出的關係,不必非要橫軸 x、縱軸 y;向量場也是同一個思路。他想要一個足夠靈活的東西,讓人不被“座標圖”這種視覺正規化困住。

同時他又想吃到程式碼的紅利。如果一個場景需要按引數微調,或者要按條件走不同分支,或者要造出任意增長的複雜度,那就該用迴圈、條件、抽象這些程式設計原語去做。反過來,只是往螢幕上打字、挪幾個方塊,用 Keynote 就夠。真正的手藝,是把該寫程式碼的那部分拆出來丟進 Manim,剩下的交給別的工具。

問他 Python 最滿意和最不滿意的地方。最滿意:它既是物件導向的,又是函式式的,你可以按需要挑一種結構來組織東西。想快速

想快速拼個原型,函式式那套很順手。Python 對他來說是“家”。最不滿意:慢。做計算密集的事情,要麼得多想一步怎麼最佳化,要麼就乾等著。

Manim 老版本的渲染慢得離譜,後端處理方式“幾乎是荒謬的”。他後來重寫成全部走 shader,硬活交給 GLSL 在 GPU 上算,快到開發過程中可以實時互動:3D 場景能隨手轉,元素能跟著滑鼠動。觀眾體驗不到這些,因為影片只有播放和暫停兩個按鈕,但寫程式碼的時候那種手感完全不一樣。

然後 Lex 問了個很程式設計師的問題:你怎麼看海象運算子(walrus operator)?

格蘭特的第一反應很淡:我不太在乎,兩邊都行。直覺上它讓程式碼更難讀,但列表推導一開始也難讀。用得慣就用,用不慣就不用,關於空格還是 Tab 的那些爭論,大家都冷靜點。

Lex 提到它背後的故事:Python 3.8 引入這個運算子時,核心開發者裡的反對聲音極大,那場討論的毒性最終累積到 Guido van Rossum 卸任 BDFL(終身仁慈獨裁者)。格蘭特說,那大概是毒性最濃的一次討論,反對 Guido 決定的開發者數量是歷來最多的。他本人未必特別在意這個特性,只是覺得批了是個好主意,然後他不喜歡隨之而來的那些負面情緒。

Lex 說,這件事在他看來體現了開源社群裡優秀領導力的價值。偉大的領導者會在還有分歧的時候做決定。如果每次遇到爭議都等著分歧自然消失,那就成了國會式的癱瘓。等一等是好的,但某個點上你必須往前走。

這世界不會因為你一直在等分歧消失而前進。(格蘭特·桑德森)

萬物理論是太大的一口,你根本咽不下去

2020 年物理圈挺熱鬧。埃裡克·溫斯坦(Eric Weinstein)的幾何統一,斯蒂芬·沃爾夫勒姆的物理專案,一個用幾何,一個用超圖,都打著“萬物理論”的旗號。Lex 問格蘭特怎麼看。

他的回答可能是整場對話裡最不客氣的一段。

就科普而言,人們對萬物理論的興趣,超過了他們應有的程度。(格蘭特·桑德森)

理由很直接:不管你在讀愛因斯坦的講義、沃爾夫勒姆的專案,還是聽人講弦論,你其實不會真的理解它在說什麼。少數物理學家會,但你不會。所以花在這個方向上的注意力,回報極低。

他說更有生產力的是另一條路:讓自己真正對某些仍然深刻、但你確實有機會搞懂的現象發生興趣。

他舉了個例子,來之前剛看的 Steve Mould 的影片,講糖為什麼會讓光以某種方式偏振。要真搞懂這件事,你得往下挖圓偏振光到底是什麼意思,而這條線能把你帶到對二態量子系統相當不錯的理解。相比之下,你去讀“量子場論和廣義相對論為什麼難以統一”,永遠到不了那兒。

所以他的判斷是雙向的:觀眾該比現在更少關注萬物理論,科普者該比現在更剋制。對真正做物理的人也許不是這樣,但科普這條線是。

而且還有一個現實約束:你幾乎不可能做出一支 3Blue1Brown 風格的萬物理論影片。它沒法在二十分鐘裡被真正講清楚。

費馬大定理的 n 等於 3,和孿生素數的誘惑

他順勢講了個例子。如果他要做費馬大定理的影片,他不會去講懷爾斯的證明,而會講 n 等於 3 的特例。這個情形仍然勉強可及。

裡面涉及到的東西挺硬:看數字所在的數域,它在複平面里長得像個六邊形格,然後你在這個格上問因式分解的問題。他之前在其他語境裡講過這種格上的算術,觀眾能走到理解那一步。而讓費馬大定理真正難的東西,比這深得多。你想理解一般情形為什麼難,必須先走完這些可及的路。跳過它們直接講一般情形,只能講得淺,浪費觀眾的時間。

他還講了小時候的一段。孿生素數猜想曾經把他整個吸進去,因為它看得懂。他有過一個夢想:也許我就是證明它的人。那段時間他學任何新數學,都會拿它當透鏡看,想著這個能不能用上。

然後人會長大,會意識到一件事:你該把腦力花在那些你能看到它被解決的問題上。因為只有看到問題被解決,你才知道“解決”是什麼感覺,才會長。

你應該把腦力花在你能看到被解決的問題上,而不是花在那些不會在你手上開花的事情上。(格蘭特·桑德森)

他舉了詹姆斯·梅納德(James Maynard)作為正面例子:年輕、有創造力,不去正面硬剛孿生素數猜想,而是去找一批因為相似原因而難、但變得可處理的問題,讓自己真正扎進去。

“生命的意義”這個問題,缺一個主語

最後 Lex 問了個大問題:生命的意義是什麼?

格蘭特說他不理解這個問題。

意義是被賦予給那些帶著意圖被創造出來的東西的。(格蘭特·桑德森)

這個水瓶上的標籤有意義,因為有人帶著“把某個意思傳達給另一個意識”的目的把它做了出來。絕大多數東西沒有這個屬性。所以問“生命的意義”,有點像問“高度是多少”:你不能脫離物件問高度,也不能脫離一個帶意圖的意識問意義。他說這大概暴露了他不太宗教。

但他也不認為提問的人是空的。他猜人們實際在問的可能是:我每天做決定的時候,該做什麼?那盞指引的燈是什麼?

如果是這個問法,他的答案很樸素:與他人的互動,與想法相近的人的互動。給別人帶來快樂。你創造的東西以某種方式與人連線上,反過來也一樣。我們用“意義”這個詞形容的那種被幸福和能量填滿、想繼續創造更多的狀態,他從這裡得到了太多。

Lex 追問:那一個人獨自待在荒島上,是不是就沒什麼意義了?

我覺得我們都是孤獨地在一起。(格蘭特·桑德森)

一朵花,和科學只做加法

節目最後,Lex 放了費曼的一段話,講一位藝術家朋友。

他會舉起一朵花說,看多美。我同意。然後他說,我作為藝術家能看到它有多美,但你作為科學家把它拆開,它就變乏味了。我覺得他有點瘋。首先,他看到的美,對別人、對我同樣存在。同時,我看到的花比他多得多:我能想象裡面的細胞,裡面複雜的活動,那也是一種美。不只是那一釐米尺度上的美,還有更小尺度上的美,內部結構,還有過程。花的顏色演化出來是為了吸引昆蟲傳粉,這很有意思,這意味著昆蟲能看到顏色。這又引出一個問題:這種審美感在更低等的生命裡也存在嗎?為什麼是審美的?科學知識只會給花增加興奮、神秘和敬畏。它只會增加。我不理解它怎麼減少。(理查德·費曼)

這段話放在整場對話的結尾,回頭再看前面那些內容,會發現線索是通的。

格蘭特說費曼讀論文要先自己解一遍,說拓撲學被講成了黏土的性質,說費曼效應讓你爽卻留不下東西,說最有資格講的人最不敢點發布。這幾件事指向同一個方向:真正理解一件事,需要你自己走一遍那段路,被別人的順滑敘事帶著滑過去是不夠的。

科學只做加法。這句話既是費曼的,某種程度上也是 3Blue1Brown 這個頻道存在的理由。

如果這篇讀完你想做點什麼

  • 挑一個主題,一年只做一個。選你最懂、最熱愛的那一個,做出這個世界上關於它最好的一支講解。就一個。所有領域的行家都這麼做一次,網際網路上你想學的任何東西都會有一支能看的影片。
  • 寫東西的時候拔網線。想查的內容先記在便籤上,等允許上網時統一查。卡住的時候去讀點東西,讀十五到三十分鐘,不相關也行,然後再回來寫。
  • 不要先立專案再去學。平時在背景裡廣泛地學,等某個“啊哈”的瞬間自己冒出來,再把它放進可做的清單。沒有那個串起全片的瞬間,就別開工,否則要麼卡死,要麼講不好。
  • 學新東西時,挑幾個核心概念先自己推一遍。哪怕慢,哪怕繞遠。你會自動去構造反例和邊界情況,長出來的直覺是別人給不了的。
  • 用睡蓮的百分之一版本校準你的直覺。下次看到“增長很快”的資料,別問“什麼時候到一半”,先算“到百分之一要多久”。那個數字通常會讓你重新估計自己還剩多少時間。
  • 面對宏大敘事時,先問自己能不能算到底。萬物理論、終極統一、顛覆性突破,這類話題的閱讀快感極高,留存率極低。找一個深刻但你能真正推完的問題,走一遍完整的路。
  • 如果你在創作:把評論區當成有偏樣本。沉默的大多數既不留讚美也不留批評。想校準自己,去看留存曲線和完播率,別去看留言。
  • 如果條件允許,給自己排一個“沒有具體議程”的會議。遠端辦公拿走的那些偶遇,得靠人為製造補回來一點。
文稿由本站用語音識別模型(基於官方釋出音訊)機器轉寫,可能有識別錯誤,人名與數字請以音訊為準。
[00:00:00] The following is a conversation with Grant Sanderson, his second time on the podcast, he's known to millions of people as the mind behind three Blue One Brown, a YouTube channel where he educates, inspires the world with the beauty and power of mathematics. [00:00:15] Quick summary of the sponsors. Dollar Shave Club Door Dash and cash app click. The sponsor links in the description to get a discount and to support this podcast, especially for the two new sponsors, Dollar Shave Club and Door Dash. Let me say as a side note, I think that this pandemic challenge millions of educators to rethink how they teach, to rethink the nature of education. As people know, Grant is a master elucidates of mathematical concepts that may otherwise seem difficult or out of reach for students and curious minds. [00:00:47] But he's also an inspiration to teachers, researchers and people who just enjoy sharing knowledge like me. For what it's worth, it's one thing to give a semester's worth of material lectures. It's another to extract from those lectures the most important, interesting, beautiful and difficult concepts and present them in a way that makes everything fall into place. That is the challenge that is worth taking on. My dream is to see more and more of my colleagues at MIT and world experts across the world summon their inner three blue one brown and create the canonical explainer videos on a topic that they know more than almost anyone else in the world. [00:01:25] Amidst the political division, the economic pain, the psychological medical toll, the virus masterfully crafted educational content feels like one of the beacon of hope that we can hold on to. If you enjoy this thing, subscribe on YouTube review, starting up a podcast, follow on Spotify, support on page one or connect with me on Twitter. Allex Friedman, of course, after you go immediately, which you already probably have done a long time ago, and subscribe to three blue and brown YouTube channel. [00:01:56] You will not regret it. As usual, I do a few minutes of hours now and no ads in the middle, I try to make these interesting, but I give you time stamps you can skip, but still, please do check out the sponsors by clicking the links in the description, especially the two new ones, Jordache and Dollar Shave Club. They're evaluating us, looking at how many people go to their site and get their stuff in order to determine if they want to support the long term. [00:02:21] So you know what to do. [00:02:23] The best way to support this podcast is always the show sponsored by Dollar Shave Club. Try them out with a one time offer for only five dollars and free shipping. A dollar shave club dotcom slash lex starter kit comes with a six blade, razor refills and all kinds of other stuff that makes shaving feel great. I've been a member of Dollar Shave Club for over five years now and I actually signed up when I first heard about them on the Joe Rogan podcast and now we've come full circle. [00:02:53] I feel like I've made it now that I can do a read for them, just like Joe did. And all those years ago, for the most part, I've just used the razor and the refills. But they encouraged me to try the shave butter, which I've never used before. So I did. And I love it. Not sure how the chemistry of it works out, but it's translucent somehow, which is a cool new experience. Again, try the ultimate shave starter set today for just five bucks, plus shipping a dollar shave club dotcom slash Lex that shows also sponsored by Dorda. [00:03:24] Get five bucks off and your delivery fees and your first order of fifteen dollars or more when you download the door dash app and enter code leks. I have so many memories of working late nights for deadline with a team of engineers and eventually taking a break to argue about which Jordache restaurant to order from and when the food came. Those moments of bonding, of exchanging ideas, of pausing to shift attention from the programs to the humans or special. These days, for a bit of time, I'm on my own, sadly, so I miss that camaraderie. [00:03:58] But actually Doordarshan is still there for me. There's a million options that fit into my keto diet ways. Also, it's a great way to support restaurants in these challenging times. Once again, download a door dash app and enter collects to get five bucks off your delivery fees and your first order of fifteen dollars or more. Finally, this show is presented by Kashyap, the number one finance app in the App Store, when you get it, Use Collects podcast, catch up, lets you send money to friends, buy Bitcoin and invest in the stock market with as little as one dollar. [00:04:30] It's one of the best design interfaces of an app that I've ever used to make. Good design is when everything's easy and natural. That design is when the app gets in the way. Is it because it's buggy? Because it tries too hard to be helpful? I'm looking at you, Clippy. Anyway, there's a big part of my brain and heart that loves to design things and also to appreciate great design by others. So again, if you get cash out from the App Store, Google Play and use called Legs podcast, you get ten dollars in cash. [00:04:59] Apple also donate ten dollars to First, an organization that is helping to advance robotics and stem education for young people around the world. And now here's my conversation with Grant Sanderson. You've spoken about Richard Feynman as someone you admire. I think last time we spoke, we ran out of time, so I wanted to talk to you about him. [00:05:41] Who is Richard Feynman to you and your eyes? What impact did he have on you? [00:05:46] I mean, I think a ton of people like Feynman, he's probably it's a little bit cliched to say that you like Feynman, right? That's almost like when you don't know what to say about sports and you just point to the Super Bowl or something as something you enjoy watching. [00:05:58] But I do actually think there's a layer to Feynman that, like, sits behind the iconography. One thing that just really struck me was this letter that he wrote to his wife two years after she died. So doing the Manhattan Project, she had polio. Tragically, she died. They were just young, madly in love. And, you know, the icon of Feynman is this almost this like mildly sexist, womanizing philanderer, at least on the personal side. [00:06:25] But you read this letter and they can try to pull it up for you if I want. And it's just this absolutely heartfelt letter to his wife saying how much he loves her even though she's dead and kind of what she means to him, how no woman can ever measure up to her. And it shows you that the fine men that we've all seen in, like, surely you're joking is different from the fine men in reality. And I think the same kind of goes in his science where, you know, he kind of sometimes has this out of being this Ashok's character, like everyone else is coming in this with these fancy faluting formulas. [00:06:56] But I'm just going to try to whittle it down to its essentials, which is so appealing because we love to see that kind of thing. But when you get into it like. What he was doing was actually quite deep, very much mathematical, that should go without saying, but I remember reading a book about Feynman in a cafe once and this woman looked at me and was like, I saw that it was about Feynman. She was like, Oh, I love him. [00:07:16] I read, you're joking. And she started explaining to me how he was never really a math person. And I don't understand how that can possibly be a public perception about any physicist. But for whatever reason, that, like, worked into his or that he sort of shut off math in place of true science. The reality of it is he was deeply in love with math and was much more going in that direction and had a clicking point into seeing that physics was a way to realize that. [00:07:39] And all the creativity that he could output in that direction was instead poured towards things like fundamental, not even fundamental theories, just emergent phenomena and everything like that. So. To answer your actual question, like what what I like about his way of going at things is this constant desire to reinvent it for himself. Like when he would consume papers, the way he'd describe it, he's he would start to see what problem he was trying to solve and then just try to solve it himself to get a sense of personal ownership and then from there see what others had done. [00:08:09] Is that how you see problems yourself? Like, that's actually an interesting point when you first. Are inspired by a certain idea they maybe want to teach or visualize or just explore on your own. I'm sure you're captured by some possibility of magic of it. Do you read the work of others? Like do you go through the process? Do you try to rediscover everything yourself? [00:08:31] So I think the things that I've learned best and have the deepest ownership of are the ones that have some element of rediscovery. The problem is that really slows you down. And this is for my part, it's actually a big fault. Like this is part of why I'm I'm not an active researcher. I'm not like at the depth of the field. A lot of other people are the stuff that I do there. And I try to learn it really well. [00:08:50] Um, but other times you do need to get through it at a certain pace. You do need to get to a point of a problem you're trying to solve. So obviously you need to be well equipped to read things without that reinvention component and see how others have done it. But I think if you choose a few core building blocks along the way and you say, I'm really going to try to approach this before I see how this person went at it, I'm really going to try to approach it for myself. [00:09:13] No matter what. You gain all sorts of articulable intuitions about that topic, which aren't going to be there. If you simply go through the proof, for example, you're going to be trying to come up with counterexamples. You're going to try to come up with intuitive examples, all sorts of things where you're populating your brain with data and the ones that you come up with are likely to be different than the one that the text comes up with. And that, like, lends it a different angle. [00:09:36] So that aspect also slowed Feynman down in a lot of respects. I think there was a period when, like the rest of physics was running away from him. But insofar as got it, got him to where he was, I kind of resonate with that. I just I would I would be nowhere near it because I not like him at all. But it's like a state to aspire to, you know, just to telling. And a small point you made that you're not, quote unquote, active researcher. [00:10:05] Do you hear swimming often in reasonably good depth about a lot of topics? [00:10:12] Do you sometimes want to, like, dive deep at a certain moment and say, like, because you probably built up a hell of an amazing intuition about what is and isn't true within these worlds? Do you ever want to just dive in and see if you can discover something new? [00:10:31] Yeah, I think one of my biggest regrets from undergrad is not having built better relationships with the professors I had there. And I think a big part of success in research is that element of like mentorship and like people giving you the kind of scaffolded problems to carry along from my own, like, goals. Right now, I feel like, um, I'm pretty good at exposing math to others and like, I want to continue doing that for my personal learning. [00:10:56] I. Are you familiar with, like, the hedgehog fox dynamic? I think this was either the ancient Greeks came up with it or it was pretended to be something drawn from the ancient Greeks that I don't know who to point it to, but they probably Mark Twain. It is that you've got two types of people, or especially two types of researchers. There's the Fox that knows many different things and then the hedgehog that knows one thing very deeply. [00:11:21] So like von Neumann would have been the fox. He's someone who knows many different things, just very foundational, a lot of different fields. Einstein would have been more of a hedgehog thinking really deeply about one particular thing, and both are very necessary for making progress. So between those two, I would definitely see myself as like the fox, where I'll try to get my powers in like a whole bunch of different things. And at the moment, I just think I don't know enough of anything to make a significant contribution to any of them. [00:11:46] But I do see value in like having a decently deep understanding of a wide variety of things. Like most people who know computer science really deeply don't necessarily know physics very deeply, or many of the aspects like different fields in math, even let's say you have like an analytic number theory versus an algebraic number theory, like these two things end up being related to very different fields, like some of them more complex analysis, some of them more like algebraic geometry. [00:12:13] And then when you just go out so far as to take those adjacent fields, place one, you know, PhD student into a seminar of another ones. They don't understand what the other one's saying at all. Like you take the complex analysis specialist inside the algebraic geometry seminar there is lost, as you or I would be. But I think going around it like trying to have some sense of what this big picture is, certainly has personal value for me. [00:12:33] I don't know if I would ever make like new contributions in those fields, but I do think I could make new, like expositional contributions where there's kind of a notion of, uh, things that are known but haven't been explained very well. [00:12:47] First of all, I think most people would agree your videos, your teaching, the way you see the world is fundamentally, often new, like you're creating something new. And it almost feels like research, even just like the visualizations, the multidimensional visualization we'll talk about. [00:13:05] I mean, you're revealing something very interesting. That, yeah, just feels like research feels like science. He feels like the cutting edge of the very thing of which, like new ideas and new discoveries are made of. I do think you're being a little bit more generous than is necessarily. And I promise that's not even false humility, because I sometimes think when I research a video, I'll learn like 10 times as much as I need for the video itself. [00:13:31] And it ends up feeling kind of elementary. So I have a sense of just how far away like the stuff that I cover is from the actual depth. [00:13:39] I think that's natural, but I think that could also be a mathematics thing. I feel like in the machine learning world, you like two weeks and you feel like you've basically mastered in mathematics. [00:13:50] It's like, well, everything is either trivial or impossible. And it's like a shockingly thin line between the two where you can find something that's totally impenetrable. And then after you get a feel for it's like, oh yeah, that whole that whole subject is actually trivial in some way. So maybe that's what goes on. Every researcher is just on the other end of that hump and it feels like it's so far away, but one step actually gets them there. [00:14:13] What do you think about sort of Fineman's teaching style or another perspective of use of visualization? [00:14:22] Well, his teaching style is interesting because people have described like the Feynman effect, where while you're watching his lectures or while you're reading his lectures, everything makes such perfect sense. So as an entertainment session, it's wonderful because it gives you this this intellectual satisfaction that you don't get from anywhere else that you like, finally understand it. But the fundamental fact is that you can't really recall what it is that gave you that insight. You know, even a week later. [00:14:49] And this is this is true of a lot of books and a lot of lectures where the retention is never quite what we hope it is. So. There is a risk that the stuff that I do also fits that same bill where at best it's giving this kind of intellectual candy on, giving a glimpse of feeling like you understand something. But unless you do something active, like reinventing it yourself, like doing problems to solidify it, um, even things like space, repetition, memory, to just make sure that you have, like the building blocks of what do all the terms mean? [00:15:21] Unless you're doing something like that, it's not actually going to stick. So the very same thing that's so admirable about Feynman's lectures, which is how damn satisfying they are to consume, might actually also reveal a little bit of the flaw that we should, as educators all look out for, which is that that does not correlate with long term learning. We'll talk about it a little bit. [00:15:42] I think we've done some interactive stuff. [00:15:45] And even in your videos, the awesome thing that Feynman couldn't do at the time is you could sense his programmed you can like, tinker like play with stuff. You could take this value and change it. You can like heroes, take the value of this variable and change it to build up an intuition, to move along a surface or to to change the shape of something. I think that's almost an equivalent of you doing it yourself. It's not quite there. [00:16:14] But you as a viewer. Yeah. Do you think there's some value in that interactive element? Yeah. [00:16:21] Well, so what's interesting is you're saying that and the videos are not interactive in the sense that there's a play button and a pause button and you could ask like, hey, while you're programming these things, why don't you program it into an interactive version, you know, make it a Jupiter notebook that people can play with, which I should do, and that would be better. I think the thing about interactive, though, is most people consuming them, um, just sort of consume what the author had in mind. [00:16:45] And that's kind of what they want. Like, I have a ton of friends who make interactive explanations. And when you look into the analytics of how people use them, there's a small sliver that generally use it as a playground to have experiments. And maybe that small sliver is actually who you're targeting and the rest don't matter. But most people consume it just as a piece of, um, like well constructed literature that maybe you tweak with the example a little bit to see what it's getting at. [00:17:08] But in that way, I do think like a video can get most of the benefits of the interactive, like the interactive app. As long as you make the interactive for yourself and you decide what the best narrative to spend is. Um, as a more concrete example, like my process with I made this video about Essaouira models for epidemics and it's like this agent based modeling thing where you tweak some things about how the epidemic spreads and you want to see how that affects its evolution. [00:17:34] Um, my, my, uh, format for making that was very different than others were. Rather than scripting it ahead of time, I just made the playground and then I played a bunch and then I saw what stories that were to tell within that. Um, yeah, that's cool. So your video had that kind of structure. It had like five or six stories or whatever it was. And like it was basically, OK, here's a simulation, here's a model. [00:17:58] What can we discover with this model? [00:18:01] And here's five things I found after playing. Well, because the thing is a way that you could do that project is you make the model and then you put it out and you say, here's the thing for the world to play with, like come to my website where you interact with this thing and people did, like, sort of remake it in a JavaScript way so that you can go to that website and you can test your own hypotheses. But I think a meaningful part of the value to add is not just the technology, but to give the story around it as well. [00:18:27] And like, that's kind of my job. It's not just to make the, uh, the visuals that someone will look at. It's to be the one to decide what's the interesting thing to walk through here. Um, and even though there's lots of other interesting parts that one could take, that can be kind of daunting when you're just sitting there in a sandbox and you're given this tool with like five different sliders and you're told to, like, play and discover things, it's like where do you do? [00:18:49] What do you start? What are my hypotheses? [00:18:51] What should I be asking? Like, a little bit of guidance in that direction can be what actually sparks curiosity to make someone want to imagine more about it. [00:19:00] A few videos I think you do. I don't know how often you do it, but there's almost a tangential, like pause where you here's a cool thing. You say like here's a cool thing, but it's outside the scope of this video, essentially. But I'll leave it to you as homework essentially to like figure out it's a cool thing to explore. [00:19:19] I wish I could say that wasn't a function of laziness. Right. And it's like you've worked so hard on making the twenty minutes already that to extend it out even further, it would take more time. [00:19:29] And one of your cooler videos, the Homma Morphic, like from the Mobius strip to the really described rectangle. Yeah, that's a super. And you're like, yeah, well, you can't you can't transform the the Mobius strip into, uh, into a surface without intersecting itself. But I'll leave it to you to to see why that is. [00:19:53] Well I hope that's not exactly how it is, because I think it was my hope. Would be is that I leave it to you to think about why you would expect that to be true and then to want to know what. Aspects of them will be. Do you want to formalize such that you can prove that intuition that you have? Because at some point now you're starting to invent algebraic topology. If you have these vague instincts, like I want to get this Mobius strip, I want to fit it such that it's all above the plane, but it's boundary sits exactly on the plane. [00:20:25] I don't think I can do that without crossing itself, but that feels really vague. How do I formalize it? And as you starting to formalize that, that's what it's going to get you to try to come up with a definition for what it means to be Oriental or not Oriental. And like once you have that motivation, a lot of the otherwise arbitrary things that are sitting at the very beginning of a topologies textbook start to make a little more sense. [00:20:44] Yeah, and I mean that that whole video beautifully was a motivation for topologies core. [00:20:49] That was my my hope with that is I feel like topologies. I don't want to say it's taught wrong, but I do think sometimes it popularized in the wrong way where, you know, you'll hear these things of people saying, oh, topologies, they're very interested in surfaces that you can bend and stretch, but you can't cut or glue, are they? Why? [00:21:08] Well, yeah, there's all sorts of things you can be interested in with random, like imaginative manipulations of things. Is that really what like mathematicians are into? And the short answer is not not really. That's it's not as if someone was sitting there thinking, like, I wonder what the properties of clay are. They had some arbitrary rules about what when I can't cut it and when I can't glue it. Instead, it's there's a ton of pieces of math that can actually be equivalent to, like these very general structures. [00:21:38] That's like geometry, except you don't have exact distances. You just want to maintain a notion of closeness. And once you get it to those general structures, constructing mappings between them translate into non-trivial facts about other parts of math. And that I just I don't think that's actually popularized. I don't even think it's emphasized well enough when you're starting to take a topology class because you kind of have these two problems. It's like either it's too squishy. You're just talking about coffee mugs and donuts or it's a little bit too Reger first. [00:22:06] And you're talking about the axiom systems with open sets and open set is not the opposite of closed set. So sorry about that, everyone. We have a notion of open sets for ones that are both at the same time and just it's not it's not an intuitive axiom system in comparison to other fields of math. [00:22:24] So you as the student like really have to walk through mud to get there. And you're constantly confused about how this relates to the beautiful things about coffee mugs and Mobius strips and such. And it takes a really long time to actually see like see topology in the way that mathematicians see apology. But I don't think it needs to take that time. I think there's, um, this is making me feel like I need to make more videos on the topic, because I think of what you do. [00:22:46] But I've also seen it in my narrow view of like I find game theory very beautiful. And I know topology has been used elegantly to prove things in game theory. Yeah. [00:22:58] You have like facts that seem very strange. Like I could tell you, you stir your coffee and after you stir it and like, let's say all the molecules settle to, like, not moving again, one of the molecules will be basically in the same position it was before. You have all sorts of fixed point theorems like this. Right. That kind of fixed point theorem, directly relevant tinashe equilibriums. Right. So you can imagine popularising it by describing the coffee fact, but then you're left to wonder, like, who cares about if a molecule of coffee, like, stays in the same spot? [00:23:26] Is this what we're paying our mathematicians for? You have this very elegant mapping onto economics in a way that's very concrete, very I wouldn't say concrete, very tangible, like actually add value to people's lives through the predictions that it makes. [00:23:39] But that line isn't always drawn because you have to get a little bit technical in order to. Properly draw that line out and often, I think, popularized forms of media just shy away from being a little too technical for sure. [00:23:55] By the way, for people who are watching the video, I do not condone the message and the smug feeling, which is this. The snaggle is real, by the way, for anyone watching. I do condone the message of the struggles of snaggle Israel. [00:24:08] OK, so you mentioned the Sahara model. I think there are certain ideas there of growth, of exponential growth, what? Maybe have you learned about pandemics from from making that video because it was kind of exploratory? We're kind of building up an intuition and it's again, people should watch the video. It's kind of an abstract view. [00:24:36] It's not really modeling in detail the whole field of epidemiology. Those people, they go really far in terms of modeling, like how people move about. [00:24:49] I don't know if you've seen it, but like there is the mobility patterns, like how like to think how many people you encounter in certain situations when you go to school, when you go to a mall, they like model every aspect of their four particular state, like they have maps of actual city streets. They model it really well and natural patterns of the people have it's crazy. So you don't do any of that is just doing an abstract model to explore different ideas of simple. [00:25:16] Well, because I don't want to pretend like anybody. I'm an epidemiologist like we have a ton of armchair epidemiologists and the spirit of that was more like I can we threw a little bit of play, draw like reasonable ish conclusions and also just like get ourselves in a position where we can judge the validity of a model. [00:25:35] Like, I think people should look at that and they should criticize it. They should point to all the ways that it's wrong because it's definitely naive, right in the way that it's set up. But to say, like what what lessons from that whole like thinking about the are non-value and what that represents and what it can imply are not so are not is if you are infectious and you're in a population which is completely susceptible, what's the average number of people that you're going to infect during your infectiousness? [00:26:04] So certainly during the beginning of an epidemic, this basically gives you kind of the the exponential growth rate. Like if every person infects two others, you've got that one two four eight exponential growth pattern as it goes on. And let's say it's something endemic where you've got like a ton of people who have had it and are recovered, then you would the are not value doesn't tell you that as directly because a lot of the people you interact with aren't susceptible. [00:26:32] But in the early phases it does. And this is like the fundamental constant that it seems like epidemiologists look at. And, you know, the whole goal is to get that down. If you can get it below one, then it's no longer epidemic. If it's equal to one, then it's endemic and it's above one, then your epidemic. So, like just hitting what that value is and giving some intuitions on how do certain changes in behavior change that value? [00:26:55] And then what does that imply for exponential growth? I think those are general enough lessons and they're like resilient to all of the chaos of the world that it's still valid to take from the video. [00:27:09] I mean, one of the interesting aspects of that is just exponential growth. And we think about growth that one of the first times you've done a video and on. No, of course not. [00:27:20] The whole Euler's identity. [00:27:24] OK, so I'm sure I've done a lot of videos about exponential growth in the circular direction, only minimal in the normal direction. [00:27:32] I mean, another way to ask, like, do you think we're able to reason intuitively about exponential growth? It's funny, I think it's I think it's extremely intuitive to humans and then we train it out of ourselves such that it's then really not intuitive. And then I think it can become intuitive again when you study a technical field. So what I mean by that is, have you ever heard of these studies where in a like anthropological setting where you're studying a group that has been disassociated from a lot of like modern society and you ask what number is between one and nine, then maybe you would ask it. [00:28:09] You've got like one rock and you've got nine rocks. You're like, what pile is halfway in between these? And our instinct is usually to say five. That's the number that sits right between one and nine. But sometimes when numeracy and the kind of just basic arithmetic that we have isn't in a society, the natural instinct is three because it's in between in an exponential sense and a geometric sense that one is three times bigger and then the next one is three times bigger than that. [00:28:35] So it's like what's you know, if you have one friend versus one hundred friends, what's in between that? Yeah, ten friends. Seems like the social status in between those two states. So that's like deeply intuitive to us to think logarithmically like that. Um, and for some reason we kind of train it out of ourselves to start thinking linearly about things. [00:28:52] So in the sense that early, early, basic math is it forces us to take a step back. It's the same criticism if there's any if science is the lessons of science. Make us like see the world in a slightly narrow sense to where we. We have an overexaggerated confidence that we understand everything as opposed to just understanding a small slice of it. But I think that probably only really goes for small numbers, because the real counterintuitive thing about exponential growth is like as the numbers start to get big. [00:29:27] So I bet if you took that same set up and you ask them, oh, if I keep tripling the size of this RockPile, you know, seven times, how big will it be? I bet it would be surprisingly big even to like a society without numeracy. And that's the side of it that I think is pretty counterintuitive to us. But that you can basically train into people like, I think computer scientists and physicists when they're looking at the early numbers of like covid were they were the ones thinking like, oh, God, this is following an exact exponential curve. [00:29:58] Yeah. And I heard that from a number of people. So it's an almost all of them are like techies in some capacity, probably just because I live in the Bay Area. But but for sure, they're cognizant of this kind of this kind of growth as president. A lot of natural systems and a lot of in a lot of. And a lot of systems, I don't know if you seen like I mean, there's a lot of ways to visualize this, obviously, but Ray Kurzweil, I think, was the one that had this, like, chess board. [00:30:27] Where every every square on the chessboard, you double the number of stones or something in that chessboard over this is like an old proverb where it's like, you know, someone the king offered him a gift and he said, the only gift I would like, very modest, give me a single grain of rice rice. So this is a chessboard. And then two grains of rice for the next square, then twice that for the next square and just continue on. [00:30:49] That's my only modest ask yourself. And like, you know, more grains of rice than there are anything in the world. By the time you get to the end and I, I, my intuition falls apart there, like I would have never predicted that. Like, for some reason, that's a really compelling illustration of how poorly breaks down. Just like you said, maybe we're OK for the first few piles of rocks, but after a while it's game over. [00:31:17] You know, the other classic example for gauging someone's intuitive understanding of exponential growth is I've got like a lily pad on unlink, really big lake like Lake Michigan. And that lily pad replicates it doubles one day and then it doubles the next day and the next day. And after 50 days, it actually is going to cover the entire lake. Okay, so after how many days does it cover? Half the lake. Forty nine. [00:31:45] So you have a good instinct for exponential growth. So I think a lot of like the knee jerk reaction is sometimes to think that it's like half the amount of time or at least be like surprised that like after 49 days you've only covered half of it. Yeah. I mean, that's the reason you heard a pause for me. I literally thought that can't be right. [00:32:05] Right. Yeah, exactly. So even when you know the fact and you do the decision, it's like, wow. So you've gotten like that whole time. And then before nine it's only covering half. And then after that it gets the whole thing. But I think you can make that even more visceral if rather than going one day before you say how long until it's covered one percent of the lake. Right. And it's so what would that be? [00:32:25] Um, how many times you have to double take it over? A hundred, like seven, six and a half times. Something like that. So at that point you're looking at 43, 44 days into it. You're not even at one percent of the lake. So you've experienced, you know, 44 out of 50 days. And you're the guy that lilypad it's just one percent of the lake. But then next thing you know, it's the entire lake. [00:32:45] He wearing a space x shirt, so I'm sure let me ask you, one person who talks about exponential, you know, just the miracle of the exponential function in general. Elon Musk. [00:32:59] So he kind of advocates the idea of exponential thinking, you know, realizing that technological development can, at least in the short term, follow exponential improvement, which breaks apart our intuition, our ability to reason about what isn't isn't impossible. So he's a big one. It's a good leadership kind of style of saying, like, look, the thing that everyone thinks is impossible is actually possible because exponential. But what's your sense about about that kind of we see the world. [00:33:36] Well, so I think it's it can be very inspiring to note when something like Moore's Law is another great example where you have this exponential pattern that holds shockingly well and it enables just better lives to be led. I think the people who took Moore's Law seriously in the 60s, we're seeing that, wow, it's not going to be too long before, like these giant computers that are either batch processing or time shared, you could actually have one small enough to put on your desk on top of your desk and you could do things. [00:34:03] And if they took it seriously, like you have people predicting smartphones, like a long time ago, and it's only out of, like kind of this. I don't want to say faith in exponential, but an understanding that that's what's happening. What's more interesting, I think, is to really understand why exponential growth happens and that the mechanism behind it is when the rate of change is proportional to the thing in and of itself. So the reason the technology would grow exponentially is only going to be if the rate of progress is proportional to the amount that you have so that the software you write enables you to write more software. [00:34:37] And I think we see this with the Internet, like the advent of the Internet makes it faster to learn things, which makes it faster to create new things. Um, I think this is oftentimes why, like investment will grow exponentially, that the more resources a company has, if it knows how to use them well, the more the more it can actually grow. So, I mean, you know, you referenced Elon Musk. I think he seems to really be into vertically integrating his companies. [00:35:04] I think a big part of that is because you have the sense what you want is to make sure that the things that you develop, you have ownership of in that they enable further development of the adjacent parts. Right. So it's not just this. You see a curve and you're blindly drawing a line through it. What's much more interesting is to ask when do you have this proportional growth property? Because then you can also recognize when it breaks down, like in an epidemic, as you approach saturation that would break down, as you do anything that skews what that proportionality constant is, you can make it maybe not break down as being an exponential, but it can seriously slow at that exponential rate is the opposite of a pandemic is you want well, in terms of ideas, you want to minimize barriers that prevent the spread. [00:35:48] You want to maximize the spread of impact. So like you want it to grow when you're doing technological development is so that you do hold up, that rate holds up. [00:35:58] And that's that's almost like a like an operational challenge of like how you run a company, how you run a group of people, is that any one invention has a ripple that's unstopped. And that ripple effect then has its own ripple effects and so on. And that continues. Yeah, like Moore's Law is fascinating. And that like on a psychological level. On a human level, because it's not exponential, it's it's just a consistent set of like what you call like askers, which is like it's constantly like breakthrough innovations non-stop. [00:36:34] That's a good point. Like it might not actually be an example of exponential because of something which grows in proportion to itself, but instead it's almost like a benchmark that was set out that everyone's been pressured to meet. And it's like all these innovations in micro inventions along the way, rather than some consistent sit back and just let the lilypad grow across the lake phenomenon. And it's also that there's a human psychological level for sure of like the four minute mile, like there's something about it like saying that, look, there is you know, Moore's Law is the law. [00:37:08] So, like, it's it's certainly an achievable thing. You know, we achieved it for the last decade, the last two decades, last three decades. You just keep going and it somehow makes it happen. [00:37:21] And it makes people I'm continually surprised in this world how few people do the best work in the world, like in that particular whatever their field is. I guess very often that like the genius. [00:37:39] I mean, you could argue that community matters, but it's certain, like I've been in groups of engineers were like. One person is clearly like doing an incredible amount of work and just is the genius and it's fascinating to see basically it's kind of the Steve Jobs idea is maybe the whole point is to create an atmosphere where the genius can discover themselves like like have the opportunity to do the best work of their life. And. Yeah, and that the exponential is just milking. [00:38:13] That is like replacing the idea that it's possible. And that idea that it's possible finds the right people for the four minute mile Najia that is possible, finds the right runners to run it and then explodes the number of people who can run faster than four minutes. It's kind of interesting to I don't know, basically the positive way to see that is most of us are way more intelligent, have way more potential than we ever realize because it's kind of depressing. [00:38:41] But I mean, like the ceiling for most of us is much higher than we ever realize. [00:38:45] That is true. A good book to read, if you want. That sense is peak, which essentially talks about peak performance and a lot of different ways, like, you know, chess, London cab drivers, how many push ups people can do, short term memory tasks. And if there's one, it's meant to be like a concrete manifesto about deliberate practice and such. But the one sensation you come out with is, wow, no matter how good people are at something, they can get better and like way better than we think they could. [00:39:12] I don't know if that's actually related to exponential growth, but I do think it's a true phenomenon. [00:39:17] It's interesting. Yeah. I mean, there's certainly no law of exponential growth in human innovation. [00:39:24] Well, I don't know what kind of there is. Like, there's I think it's really interesting to see when innovations in one field allow for innovations and another like the advent of computing seems like a prerequisite for the advent of chaos theory. You have this truth about physics and the world that in theory could be known. You could find Lorenz's equations without computers, but in practice, it was just never going to be analyzed that way unless you were doing like a bunch of simulations and that you could computationally see these models. [00:39:53] So it's like physics allowed for computers, computers allowed for better physics and, you know, wash, rinse and repeat that. So proportionality, that's exponential. So I think I wouldn't think it's too far to say that that's a law of some kind. Yeah, a fundamental law of the universe is that these descendants of apes will exponentially improve their technology in one day to be taken over by the Ajai. That's that's built in this. They'll make the video game fun, whoever created this thing. [00:40:26] I mean, since you're wearing a space shirt in the mask, I didn't realize it, but I apologize for you. [00:40:34] That's on top. Yeah. [00:40:35] So could Dragon, the first crewed mission out into space since the space shuttle and just. By first time ever by a commercial company, I mean, it's an incredible accomplishment, I think, but it's also just an incredible and it inspires imagination amongst people that this is the first step in a long, vibrant journey of humans into space. Oh, yeah. So what what are your how do you feel? Is this is this exciting to you? [00:41:12] Yeah, it is. I think it's great the idea of seeing it basically done by smaller entities instead of by governments. I mean, it's a it's a heavy collaboration between SpaceX and NASA in this case, but moving in the direction of not necessarily requiring an entire country and its government to make it happen, but that you can have something closer to a single company doing it. We're not there yet because it's not like they're unilaterally saying like we're just shooting people up into space. [00:41:36] Um, it's just a sign that we're able to do more powerful things with smaller groups of people. Uh, I find that inspiring. [00:41:43] And very quickly, I hope we see people land on Mars in my lifetime. Do you think we will? I think so. [00:41:49] And I think there's a ton of challenges there, like radiation being kind of the biggest one. And I think there's a ton of people who look at that and say, why? [00:41:59] Why would you want to do that? Let's let the robots do the science for us. But I think there's enough people who are, like, genuinely inspired about broadening, like, the worlds that we've touched, um, or people who think about things like backing up the light of consciousness with like super long term visions of terraforming, like as long as there's a backing up the light of consciousness. Yeah. The thought that, you know, if we if Earth goes to hell, we got to have a back up somewhere. [00:42:23] Um, a lot of people see that is pretty out there and it's like not in the short term future, but I think that's an inspiring thought. I think that's a reason to look it up in the morning. And I feel like most employees at SpaceX feel that way, too. [00:42:35] Do you think we'll colonize Mars one day? No idea like either ajai kills us first or if we like, allowed, I don't know if it'll take allowed allowed like honestly it takes it would take such a long time, like, OK, you might have a small colony. [00:42:48] Right. Something like what you see in the Martian, but not like people living comfortably there. Um, but if you want to talk about actual like second earth kind of stuff, that's just like way far out there and the future moves so fast that it's hard to predict, like we might just kill ourselves before that even becomes viable. I yeah. [00:43:11] I mean, there's there's a lot of possibilities where it could be just it doesn't have to be on a planet or it could be floating out in space, have to have have a have a space faring backup solution that doesn't have the doesn't have to deal with the constraints of the planet. I mean, a planet provides a lot of possibilities and resources, but also some constraints now. I mean, for me, for some reason, it's deeply exciting possibility. [00:43:36] Oh yeah. And all of the people who are like skeptical about it are like, why? Why do we care about going to Mars? Like, what makes you care about anything backfiring? It's hard, actually. [00:43:46] It is hard to hear that because exactly as you put it on a philosophical level, it's hard to say why do anything? I don't know. It's it's like the people say like. [00:43:58] Oh, you know, I've been doing like an insane challenge last 30 something days, you pull ups and pull ups and push ups and like. You know, a bunch of people are like, awesome, you're insane, but awesome. And then some people are like, why? [00:44:16] Why I do anything? I don't know. There's there's a calling. It's I'm with JFK a little bit as because we do these things because they're hard. There's something in the human spirit that is like saying, what, like a math problem? There's something you fail once. And it's like this feeling that, you know, I'm not going to back down from this. There's something to be discovered in overcoming this thing. [00:44:42] Well, what I like about it is and I also like this about the moon missions. Sure. It's kind of arbitrary, but you can't move the target, so you can't make it easier and say that you've accomplished the goal. And when that happens, it just demands actual innovation. Right. Like protecting humans from the radiation in space on the flight there. While their hard problem demands innovation, you can't move the goalpost to make that easier. Almost certainly the innovations required for things like that will be relevant in a bunch of other domains, too. [00:45:11] So like the idea of doing something merely because it's hard, it's like loosley, productive, great. But as long as you can't move the goalposts, there's probably going to be these secondary benefits that like we should all strive for. [00:45:24] Yeah, I mean, it's hard to formulate the Mars colonization problem as something that has a deadline, which is the problem. [00:45:32] But if there was a deadline, then the amount of things we would come up with by forcing ourselves to figure out how to colonize that place would be just incredible. This is what people like. [00:45:47] The Internet didn't get created because people sat down and try to figure out how do I have, you know, send Tic-Tac videos of myself dancing to people. They you know, it was there's an application. I mean, actually, I don't even know. What do you think the application for the Internet was when it was? It must have been very low level basic network communication within DARBA, like a military base, like how do I send like a networking? [00:46:15] How do I send information securely between two places? Maybe it was an encryption until totally speaking totally outside of my knowledge, but like it was probably intended for a very narrow small group of people. [00:46:27] Well so I mean it was there was like the small community of people who are really interested in timesharing computing and like interactive computing in contrast with batch processing. And then the idea that as you set up like a timesharing center, basically meaning kind of multiple people like logged in and using that like central computer, why not make it accessible to others? And this was kind of what I had always thought, like, oh, is this like fringe group that was interested in this new kind of computing? [00:46:52] And they all like got themselves together. [00:46:54] But the thing is, like, DARPA wouldn't actually you wouldn't have the U.S. government funding that just for the fun of it. Right. But in some sense, that's what ARPA was all about, was like just really advanced research for the sake of having advanced research. And it doesn't have to pay out with utility soon. But the core parts of its development were happening like in the middle of the Vietnam War when there was budgetary constraints all over the place. [00:47:18] I only learned this recently, actually. Like if you look at the documents basically justifying the budget for the ARPANET as they were developing it and not just keeping it where it was, but actively growing it while all sorts of other departments were having their funding cut because of the war. A big part of it was national defense in terms of having like a more robust communication system, like the idea of packet switching versus circuit switching. You could kind of make this case that in some calamitous circumstance where, you know, a central location gets nuked, this is a this is a much more resilient way to still have your communication lines that, like traditional telephone lines, weren't as resilient to which I just found very interesting that that, um, even something that we see is so happy. [00:48:03] Go Lucky is just a bunch of computer nerds trying to get like interactive computing out there. The actual, like thing that made it funded and thing that made it advance when it did was because of this direct national security question and concern. I don't know if you've read it. I haven't read it. I've been meaning to read it. But Neil deGrasse Tyson actually came out with a book that talks about, like science in the context of the military, like basically saying all the great science we've done and in the 20th century was like because of the military. [00:48:35] I mean, he paints a positive. It's not like a critical. It's not a lot of people say like military industrial complex and so on. Another way to see the military and national security is like a source of, like you said, deadlines and like hard things. You can't move like almost, you know, almost like scaring ourselves into product. [00:48:55] It is that I mean, the Manhattan Project is a perfect example, probably the quintessential example that one is a little bit more McJob than others because of like what they were building. But in terms of. How many focused, smart hours of human intelligence get pointed towards a topic per day, you're just maxing it out with that sense of worry. In that context, everyone there was saying, like, we've got to get the bomb before Hitler does. And that like that just lights a fire under you that I again, like the circumstances makeup. [00:49:25] But I think that's actually pretty healthy, especially for researchers that are otherwise going to be really theoretical to take these, like, theorizing and say make this real physical thing happen. Meaning a lot of it is going to be unsexy. A lot of it is going to be like young firemen sitting there kind of inventing a notion of computation in order to compute what they needed to compute more quickly with, like the rudimentary automated tools that they had available. Um, I think you see this with Bell Labs also, where you've got otherwise very theorizing minds in very pragmatic contexts that I think is like really helpful for the theory as well as for the applications. [00:50:03] So I think that sort of can be positive for progress. [00:50:07] You mentioned Bell Labs and Manhattan Project. This kind of makes me curious for the things you create, which are quite singular, like if you look at all YouTube. Or just not YouTube. It doesn't matter what it is, it's just teaching content. Art doesn't matter. It's like, yep, that's. That's Grant, right, that's unique and your teaching style and everything, does it. [00:50:34] Manhattan Project and Bell Labs was like famously a lot of brilliant people, but there's a lot of them. They play off of each other. So my question for you is it does get lonely. [00:50:45] Honestly, that right there, I think is the biggest part of my life that I would like to change in some way that I look at a Bell Labs type situation. I'm like, God damn, I love that whole situation and I'm so jealous of it. And you're like reading about Heming. And then you see that he also shared enough with his fan. And you're like, of course he did. Of course they shared an office. That's how these ideas get. [00:51:07] And they actually very likely worked separately. Yeah, totally, totally separate. But there's a literally and sorry to interrupt, there's a literally magic that happens when you run into each other, like on the way to, like, getting a snack or something. [00:51:22] Conversations you overhear, other projects you're pulled into. It's like puzzles that colleagues are sharing, like all of that. Um, I have some extent of it just because I try to stay well connected in communities of people who think in similar ways. But it's not it's not in the day to day in the same way which I would like to fix somehow. That's one of the I would say one of the biggest one of the many drawbacks, negative things about this current pandemic is that whatever the term is, but like chance collisions are significantly reduced. [00:52:01] I thought, I don't know why I saw this, but on my on my brother's work calendar, he had a scheduled slot with someone that he's scheduled a meeting. And the title of the whole meeting was No Specific Agenda. I just missed the happenstance, serendipitous conversations that we used to have with the pandemic and remote work has so cruelly taken away from us. [00:52:22] Brilliant, though the title of them is brilliant. I like that's the way to do it. You just schedule those kinds of schedule, the serendipitous interaction. [00:52:30] It's like I mean, you can't do an academic setting, but it's basically like going to a bar and sitting there just for the strangers you might meet, just the strangers or striking up conversation. Strangers on the train. [00:52:42] Harder to do when you're deeply like maybe myself or maybe a lot of academic types who are like introverted and avoid human contact as much as possible. So it's nice when it's forced those chance collisions. But maybe scheduling is a possibility, but for the most part. Do you work alone, like I'm sure you struggle, like a lot like it, like this, like you probably hit moments when you look at this and say, like this is the wrong way to show. [00:53:17] It is a long way to visualize it. [00:53:19] I'm making it too hard for myself. I'm going down the wrong direction. This is too long to short all those self-doubt that could be paralyzing. What do you do in those moments? [00:53:31] I actually much prefer, like work to be a solitary affair. For me, that's like a personality quirk. I would like it to be in an environment with others and like collaborative in the sense of ideas exchanged. But those phenomena you're describing when you say this is too long, this is too short, this visualization sucks. It's way easier to say that to yourself than it is to say to a collaborator. Um, and I know that's just the thing that I'm not good at. [00:53:53] So in that way, it's very easy to just throw away a script because the script isn't working. It's hard to tell someone else they should do the same. [00:54:00] Actually, last time we talked, I think it was like very close to me talking down. It was kind of cool. Like two people that eventually got that interview, as the heart know, can brag about something. Please. My my favorite thing is Don Knuth. After the interview, he offered to go out to hot dogs with the hot dogs. [00:54:20] But that was never like people asking, what's the favorite thing you've ever done? I mean, that has to be. But unfortunately, I couldn't. I had a thing after, so I had to turn down Don Cornelius, you, Mr. Kluth. [00:54:32] Dogs and dogs. So that was a little bragging. But the hot dogs is such a sweet. [00:54:37] So, um, but the reason I bring that up is he he works through problems alone as well. He prefers that struggle, the struggle of it. You know, writers like Stephen King often talk about like their process of, you know, what they do, like what they eat when they wake up, like when they sit down, like how they like their desk and, you know, on a on a perfectly productive day. [00:55:08] Like what they like to do, how long they like to work for, what enables them to think deeply, all that kind of stuff. Hunter S. Thompson did a lot of drugs. Everybody has their own thing. What do you ever thing is there if you were to lay out a perfect productive day or would that schedule look like, do you think? Part of that's hard to answer, because I like the mode of work I do changes a lot from day to day. [00:55:36] Like some days I'm writing the thing I have to do is write a script. Some days I'm animating. The thing I have to do is animate something as I'm like working on the animation library. The thing I have to do is like a little I'm not a software engineer, but something in the direction of software engineering. Some days it's like a variant of research. It's like learned this topic well and try to learn it differently. So those is like four very different modes of what some days is like get through the email backlog of people. [00:56:00] I've been on a task they've been putting off. [00:56:03] It goes research, scripting, like the idea starts with research and then they're scripting and then there's programming and there's the, uh, show time and the research side. [00:56:14] By the way, I like what's I think a problematic way to do it is to say I'm starting this project and therefore I'm starting the research instead. It should be that you're like ambient learning, a ton of things just in the background. And then once you feel like you have the understanding for one, you put it on the list of things that there can be a video for. Otherwise either you're going to end up roadblocked forever or you're just not going to have a good way of talking about it. [00:56:38] But still, some of the days, it's like the thing to do is learn new things. [00:56:41] So what's the most painful one? I think you mentioned scripting. Scripting is. Yeah, that's the worst. Yeah, right. Writing is the worst. So what's your perfectly. So let's take the hardest one. What's a perfectly productive day. [00:56:54] You wake up and say, damn it, this is the day I need to do some scripting and like you didn't do anything last two days, so you came up with excuses to procrastinate. So today must be the day. [00:57:04] Yeah, I wake up early, I, I guess I exercise and then I turn the Internet off. Uh, if we're writing. Yeah. That's, that's what's required is having the Internet off and then maybe you keep notes on the things that you want to Google when you're allowed to have the Internet. [00:57:21] Again, I'm not great about doing that, but when I do, uh, that makes it happen. And then when I hit writer's block, like the solution to writer's block is to read doesn't even have to be related. Just read something different. I just for like fifteen minutes, half an hour and then go back to writing that when it's a nice cycle I think can work very well. [00:57:39] And when you're writing the script you don't know where it ends. Right. Like you have a like problem solving videos. [00:57:45] I know where it ends. Expositional videos. I don't know where it ends up coming up with, uh, with the magical thing that makes this whole story like this whole story together, that ones that happen. That's that's the thing that makes it such that a topic gets put on the list of people, that's an issue and you shouldn't start the project unless there's one of those and you have so many names back that you have such a big bag of. [00:58:10] Aha. Moments already that you could just pull at. That's one of the things and one of the. Sad things about time and that nothing lasts forever and that we're all mortal. [00:58:22] Let's not get into that discussion is, you know, if I see like even when I ask for people to ask, like ask, I did a call for questions and people weren't asking questions. And so many requests from people about, like certain videos they would love you to do is such a pile. And I think that's that's a sign of, like, admiration from people for sure. But it's like it makes me sad because like whenever I see them, people give ideas. [00:58:52] They're all like very often really good ideas. And it's like it's such a makes me sad and the same kind of way. When I go through a library or through a bookstore, you see all these amazing books you'll never get to open. [00:59:09] So. So, yeah, so do you. Yeah. But I enjoy the ones that you have enjoyed the books that are open and don't let yourself lament the ones that stay closed. [00:59:19] What else is there any other magic to that day. Did you try to dedicate like a certain number of hours. Do you call Newport has this deep work kind of idea? [00:59:29] I'm there systematic people who get really on top of, you know, the checklist of what they're going to do in the day and they like count their hours. And I am not a systematic person in that way. [00:59:39] It's which is probably a problem. I very likely would get more done if I was systematic in that way. But that doesn't happen. So, you know, you talk to me, talk to me later in life, and maybe I will have, like, changed my ways and give you a very different answer. [00:59:54] I think Benjamin Franklin, like later in life, figured out the rigor. Is these like very rigorous schedules and what had to be productive? [01:00:02] I think those schedules are much more fun to write. Like it's very fun to write a schedule and make a blog post about, like the perfect, productive day, like might work for one person, but I don't know how much people get out of, like, reading them or trying to adopt someone else's style. [01:00:15] And I'm not even sure that they've ever followed. [01:00:18] Yeah, exactly. You're always going to write it as the best version of yourself. You're not going to explain the phenomenon of, like, wanting to get out of the bed, but not really wanting to get out of bed and all of that. And just like zoning out for random reasons or or the one that people probably don't touch at all is I try to check social media once a day, but I'm like only so I post and that's it. [01:00:43] When I post, I check the previous days. That's like my what I try to do. That's what I do like 90 percent of the days. But then I'll go. I'll have like a two week period where it's just like I'm checking the Internet like I mean it's some probably some scary number of times and a lot of people can resonate with that. [01:01:02] I think it's a legitimate addiction. It's like it's a dopamine addiction. And I don't know if it's a problem, because as long as it's the kind of socializing, like if you're actually engaging with friends and engaging with other people's ideas, I think it can be really useful. Well, I don't know. [01:01:18] So for sure I agree with you, but and it's a it's definitely an addiction because for me, I think it's true for a lot of people. I am very cognizant of the fact I just don't feel that happy. If I look at a day where I've checked social media a lot, like if I just aggregate I did a self report, I'm sure I would find that I'm just like literally on like the less happy with my life and myself after I've done that check. [01:01:46] When I check it once a day, I'm very like, I'm happy. I even like because I've seen it. OK, one way to measure that is when somebody says something not nice to you on the Internet is like when I check in once a day, I'm able to just like like I smile. Like I virtually I think about them positively empathetically. I send them love. [01:02:08] I don't I don't have a response, but I just feel positively about the whole thing. [01:02:13] If I check if I check like more than that, if it starts eating at me, I like start there is an eating thing that that happens. I like anxiety. It occupies a part of your mind that's not doesn't seem to be healthy. Same with. I mean, you you put stuff out on YouTube. I think it's important, I think you have a million dimensions that are interesting to you. But one of the interesting ones is the study of education and the psychological aspect of putting stuff up on YouTube. [01:02:45] I like now have completely stopped checking statistics of any kind of release. An Episode 100 with my dad conversation, my dad, he checks. He's probably listening to this stop. He checks the number of views on his and his video and his conversation. So he discovered like a reason he's new to this whole addiction and he just checks and he like he'll text me or write to me. [01:03:13] I just pass Dawkins and was like that that so much. [01:03:21] Yeah. So he's, uh. Can I tell you a funny story to that effect of leisure, parental use of YouTube early on in the channel? My mom would like text me. She's like, uh, the channel has had 990000 views. The channels had nine hundred ninety one thousand views. I'm like, oh, that's cute. She's going to be a little part on the about page where you see the total number of channel news. No, she didn't know about that. [01:03:44] She had been going every day through all the videos and then adding them up, adding them. [01:03:49] And she thought she was like doing me this favor of providing me this like global analytica that otherwise wouldn't be visible. And so it's just like this addiction where you have some number you want to follow. And then like, yeah, it's funny that your dad had this. I think what a lot of people have it. [01:04:03] I think that's probably a beautiful thing for like parents because they're legitimately they're proud. [01:04:10] Yeah. [01:04:10] They're as it's born of love. It's great. The downside, I feel when one of them is this is one interesting experience that you probably don't know much about because comments and your videos are super positive. But people judge the quality of how something went. Like, I see that with these conversations by the comments. Yeah. Like I'm not talking about like, you know, people in their 20s and their 30s. I'm talking about like CEOs of major companies who don't have time. [01:04:44] They basically they literally this is their evaluation metric. They're like, oh, the comments seem to be positive. And that's really concerning to me. [01:04:52] Most important lesson for any content creator to learn is that the commenting public is not representative of the actual public and this is easy to see. Ask yourself, how often do you read comments on YouTube videos? Most people will realize I never do it. Some people realize they do, but the people who realize they never do it should understand that that's a sign. The kind of people who are like you aren't the ones leaving comments. And I think this is important. [01:05:15] A number of respects like in my case, I think I would think my content was better than it was if I just read comments because people are super nice. The thing is, the people who are bored by it are are put off by it in some way, are frustrated by it. Usually they just go away. They're certainly not going to watch the whole video, much less leave a comment on it. So there's a huge underrepresentation of like negative feedback, like well intentioned negative feedback, because very few people actively do that, like watch the whole thing that they dislike, figure out what they disliked, articulate what they dislike. [01:05:44] Um, there's plenty of negative feedback that's not well intentioned, but for like that golden kind, uh, I think a lot of YouTube friends, I have at least have gone through phases of like anxiety about the nature of comments that stem from basically just this, that it's like people who aren't necessarily representative of who they were going for or misinterpreted what they're trying to say or whatever have you, or we're focusing on things like personal appearances as opposed to like substance. [01:06:13] And they come away thinking like, oh, that's what everyone thinks. That's what everyone's response to this video was. Um, but a lot of the people who had the reaction you wanted them to have, like, they probably didn't write it down, so. Very important to learn, it also translates to realizing that you're not as important as you might think you are because all of the people commenting are the ones who love you the most and are like really asking you to, like, create certain things or like mad that you didn't create like a past thing. [01:06:40] Um. I don't know, I have such a problem, like I have a very real problem with making promises about a type of content that I'll make and then either not following up on it soon or just like never following up on it. [01:06:51] Yeah, I actually last time we talked, I think probably I'm not sure promise to me that you'll have music incorporated into your like. [01:06:58] I'll share it with you privately. But there's an example of like what I had in mind, I like did a version of it. And like I think there's a better version of this that might exist one day. So it's now on the like the back burner. It's like it's sitting there. It was like a live performance at this one thing. I think next next circumstance that I'm like doing another recorded live performance that like fits having that been in a better recording can make it nice and public. [01:07:22] May be a while, but exactly right. Um, the point I was going to make those like I know I'm bad about following up on stuff, uh, which is an actual problem. It's borne of the fact that I have a sense of what we'll be like, good content when it won't be. [01:07:36] Um, but this can actually be incredibly disheartening because a ton of comments that I see are people who are like, uh, frustrated usually in a benevolent way that, like, I haven't followed through on like X and X, which I get. And I should do that. But what's comforting thought for me is that when there's a topic I haven't promised, but I am working on and I'm excited about, it's like the people who would really like this don't know that it's coming and don't know to like come in to that effect. [01:08:00] And like the commenting public that I'm seeing is not representative of like who I think this other project will touch meaningfully, has a focus on the future, on the thing you're creating now, just like the. [01:08:10] Yeah, the art of it. One of the people is really inspiring to me in that regard, because I've really seen it in person as Joe Rogan. He doesn't read comments, but not just that. He doesn't give a damn. He like legitimate. He's not, like, clueless about it. He's like just like the richness and the depth of a smile he has when he just experiences the moment with you. Like Off-line, you can tell he doesn't give a damn about like like. [01:08:45] About anything, about what people think about weather, if it's on a podcast, you talk to them or whether offline about just it's not there like what other people think, how how even like with the rest of the day looks like it's just deeply in the moment or like especially like is what we're doing going to make for a good Instagram photo or something like that? That doesn't look like that at all. [01:09:09] It's. I think for actually quite a lot of people, he's an inspiration in that way, but it was and in real life a show that you can be very successful not giving a damn about, about comments. And it sounds sounds bad not to read comments because it's like, well, there's a huge number of people who are deeply passionate about what you do. So you're ignoring them. Mm hmm. But at the same time, the nature of our platforms is such that the cost of listening to all the positive people who are really close to you, who are incredible people have been, you know, made a great community that you can learn a lot from. [01:09:49] The cost of listening to those folks is also the cost of your psychology. [01:09:57] Slowly being degraded by the natural underlying toxicity of the Internet is engaged with a handful of people deeply rather than like as many people as you can in a shallow way. [01:10:09] I think that's a good lesson for social media usage like platforms. [01:10:14] And generally athletes choose to just a handful of things to engage with and engage with it very well in a way that you feel proud of. And don't worry about the rest. Honestly, I think the best social media platform is texting. That's my favorite. That's my go to social media platform. Well, yeah, the best social media interaction is like real life, not social media, but social interaction. [01:10:35] Well, yeah, no, no question there. [01:10:37] I think everyone should agree with which, which sucks because it has been challenged now with the current situation. [01:10:42] And we're trying to figure out what kind of platform can be created that we can do remote communication as those effective. It's important for education. It's important for just the question of education right now. Yeah. So on that topic, you've done a series of last year called Logged On Math. And you know, you want live, which is different than you usually do, maybe one, can you talk about how that feel? What's that experience like? Like in your own when you look back? [01:11:13] Like, is that an effective way? Did you find being able to teach? And if so, is there a lessons for this world where all of these educators are now trying to figure out how the heck to teach remotely? [01:11:28] For me, it was very different. As different as you can get, I'm on camera, which I'm usually not. I'm doing it live, which is nerve wracking. It was a slightly different level of topics, although realistically I'm just talking about things I'm interested in no matter what. [01:11:41] I think the reason I did that was this thought that a ton of people are looking to learn remotely. The rate at which I usually put out content is too slow to be actively helpful. Let me just do some biweekly lectures that if you're looking for a place to point your students, if you're a student looking for a place to be edified about math, just tune in at these times. Um, and in that sense, I think it was, you know, a success for those who followed with it. [01:12:02] It was a really rewarding experience for me to see how people engaged with it. Um, part of the fun of the live interaction was to actually like I do these live quizzes and see how people would answer and try to shape the lesson based on that or see what questions people were asking in the audience. I would love to if I did more things like that in the future, kind of tighten that feedback loop even more. Um, I think for, you know, you ask about like if this can be relevant to educators, like 100 percent online teaching is basically a form of live streaming now. [01:12:32] I mean, usually it happens to resume. I think if teachers view what they're doing as a kind of performance and a kind of live stream performance, um, that would probably be pretty healthy because Zoom can be kind of awkward. Um, and I wrote up this little blog post actually just on like just what our setup looked like, if you want to adopt it yourself and how to integrate, um, like the broadcasting software OBEs with Zoom or things like that. [01:12:56] It was really sad to pause on that. I mean, yeah, maybe you can look at the blog post, but it looked really nice. [01:13:02] The thing is, I knew nothing about any of that stuff before I started. I had a friend who knew a fair bit, um, and so he kind of helped show me the ropes. One of the thing that I realized is that you could as a teacher, like it doesn't take that much to make things look and feel pretty professional. Um, like one component of it is as soon as you hook things up with the broadcasting software, rather than just doing like screen sharing, you can set up different scenes and then you can have keyboard shortcuts to transition between those scenes. [01:13:28] So you don't need a production studio with a director calling like go to camera three, go to camera two, like onto the screen instead. You can have control of that. And it took a little bit of practice and I would mess it up now and then. But I think I had a decently smooth such that, you know, I'm talking to the camera and then we're doing something on the paper. Then we're doing like a, um, playing with the demos graph or something and something that I think in the past would have required a production team you can actually do as a solo operation and in particular as a teacher. [01:13:54] And I think it's worth it to try to do that because, uh, two reasons. One might get more engagement from the students. But the biggest reason I think one of the best things that can come out of this pandemic education wise is if we train a bunch of teachers into content creators and if we take lessons that are usually done in these ONE-OFF settings and like start to get in the habit of, um, sometimes I'll use the phrase commodity's explanation where what you want is. [01:14:20] Whatever a thing a student wants to learn, it just seems inefficient to me that that lesson is taught millions of times over in parallel across many different classrooms in the world, like year to year. You've got a given algebra one lesson that's just taught like literally millions of times by different people. What should happen is that there's the small handful of explanations online that exist so that when someone needs that explanation, they can go to it, that the time in classroom is spent on all of the parts of teaching and education that aren't explanation, which is most of it. [01:14:52] Right. And the way to get there is to basically have more people who are already explaining, publish their explanations and have it in a publicized forum. So if during a pandemic you can have people. Automatically creating online content because it has to be online, but getting in the habit of doing it in a in a way that doesn't just feel like a zoom call that happened to be recorded, but it actually feels like a piece that was always going to be publicized to more people than just your students. [01:15:20] That can be really powerful. [01:15:22] And there's an improvement process there like so being self-critical and growing like, you know, I guess you two words go through this process of like putting out some content and like nobody caring about it and then trying to figure out, like, you're basically improving, figure out like, why did nobody care? What can I, you know? And they come up with all kinds of answers which may or may not be correct, but doesn't matter because the answer leads to improvement. [01:15:52] So you're being constantly self-critical yourself, analytical, and it's better to say. So you think of like, how can I make the audio better, like all the basic things. Maybe one question to ask because well, by way of Dedrick, he's a robotics professor at MIT, one of my favorite people, a big fan of yours, who watched our first conversation. [01:16:14] I just interviewed him a couple of weeks ago. [01:16:18] He he teaches this course and under robotics, which is like robotic systems, when you can't control everything, when you're like we as humans, when we walk, we're always falling forward, which means like is gravity. You can't control it. You just hope you can catch yourself. But that's not all guaranteed and depends on the. So that's undersaturated. You can't control everything or the the number of actuators, the degrees of freedom you have is not enough to fully control the system. [01:16:49] So I don't know. It's a really, I think, beautiful, fascinating class. He puts it online. It's quite popular. He does an incredible job teaching. He puts online every time. But he's kind of been interested in, like crisping it up, like, you know, making it, you know, innovating in different kinds of ways. And he was inspired by the work you do, because I think in his work he can do similar kind of explanations as you're doing, like revealing the beauty of it and spending like months and preparing a single video. [01:17:21] And he's interested in how to do that. That's why I listen to the conversation. He's playing with Manam, but he had this question of, you know. Of, you know, like in my apartment, we did the interview like curtains, like for like a black curtain. [01:17:41] This is this is a giant mansion. And that also is but you basically I have like a black curtain or whatever, you know, makes it really easy to set up a filming situation with cameras that we have here. These microphones. He was asking, you know, what kind of equipment do you recommend? I guess a blog post is a good one. I said I don't recommend this is excessive and actually really hard to work with. So I wonder, I mean, is there something you would recommend terms of equipment? [01:18:11] Like is it do you work do you think? Like lapel mikes, like USB mikes? [01:18:17] For my narration, I use a USB make for the streams. I use the lapel mike, uh, the narration. It's a blue yeti. I'm forgetting actually the name of the lapel mic, but it was probably like a road of some kind. [01:18:31] But is it hard to figure out how to make the audio sound good? [01:18:34] Oh, I mean, listen to all the early videos on my channel and clearly, like, I'm terrible at this for for some reason I just couldn't get audio for a while. I think it's weird when you hear your own voice. So you're like, this sounds weird and it's hard to know. Does it sound weird because you're not used to your own voice or they're like actual audio artifacts that play. Um. So in the video is just for the lockdown, just the camera, like you said, it was probably streaming somehow through the yeah, there were two five cameras, one that was mounted overhead over a piece of paper. [01:19:06] You could also use like an iPad or a wake up tablet to do your writing electronically. But I just wanted the paper feel, um, one on the face. There's two again, I don't know, like just not actually the one to ask this because I like animated stuff usually, but each of them, like, has a compressor object that makes it such that the camera output goes into the computer, the USB, but like it's compressed before it does that the the live aspect of it. [01:19:32] Do you do you regret doing it live? [01:19:36] Not at all. I think I do think the content might be like much less sharp and tight than if it were something even that I just recorded like that and then edit it later. But I do like something that I do to be out there to show like, hey, this is what it's like, this is what it's like when I make mistakes. This is like the piece of thinking, um, I like the live interaction of it. I think that made it better. [01:19:59] Uh, I probably would do it on a different channel, I think if I did a series like that in the future, just because it's it's a different style, it's probably a different target audience and kind of keep clean what three blue and brown is about versus, uh, the benefits of, like live lectures. [01:20:14] Do you just like in this time of covid that people like us or other educators try to go like the the shorter like twenty minute videos that are like really well planned out or scripted, you really think through, you slowly design. So it's not live. Do you see like that being an important part of what they do. [01:20:37] Yeah, well what I think teachers like Rothera do is choose the small handful of topics that they're going to do just really well. They want to create the best short explanation of it in the world. That will be one of those handfuls in a world where you have commodities do explanation, right? Most of the lectures should be done just normally. So put that and planning into it. I'm sure he's a wonderful teacher and like knows all about that. But maybe choose those small handful of topics do with beneficial for me sometimes, as if I do sample lessons with people on that topic to get some sense of how other people think about it. [01:21:09] Let that inform how you want to edit it or scripted or whatever format you want to do. Some people are comfortable just explaining it and editing later. I'm more comfortable like writing it out and thinking about setting. [01:21:19] Yeah, it's kind of sad. Sorry to interrupt. It's it's a little bit sad to me to see how much knowledge is lost. Like just just like you mentioned, there's professors like we can take my dad, for example, to blow up his ego a little bit, but he's a he's a great teacher and he knows plasma, plasma chemistry, plasma physics really well. So he can very simply explain some beautiful but otherwise complicated concepts. And it's sad that, like, if you Google plasma or like for plasma physics, like there's no videos. [01:21:55] And just imagine if every one of those excellent teachers like your father, like Russ, even if they just chose one one this year, just like I'm going to make the best video that I can on this topic. If every one of the great teachers did that, the Internet would be replete. And it's already replete with great explanations, but it would be even more so with all the great explanations and like anything you want to learn. [01:22:15] And there's a self-interest to it for in terms of teacher, in terms of even so, if you take Russ, for example, it's not that he's teaching something like he teaches his main thing, his thing he's deeply passionate about. And from a selfish perspective, it's also just like. I mean, it's a it's a it's like publishing a paper in a really like nature has like letters, like accessible publication. It's just going to guarantee that your work, that your passion is seen by a huge number of people, whatever the definition of huge is, doesn't matter. [01:22:55] It's much more than it otherwise would be. And it's those lectures that tell early students what to be interested in. Yeah. At the moment, I think students are disproportionately interested in the things that are well represented on YouTube so that any educator out there, if you're wondering, hey, I want more like grad students in my department, like, what's the best way to recruit grad students? It's like make the best video you can and then wait eight years and then you're going to have a pile of, like, excellent grad students for that department. [01:23:22] And one of the lessons I think your channel teaches is there is appeal of explaining just something beautiful, explaining a cleanly technically not doing a marketing video about why topology is great. [01:23:38] There's yeah. That's there's people interested in this stuff. Yeah. I mean, one of the greatest channels, like it's not even a math channel, but the channel with greatest math content is versus. Yeah. Like interviewed. I imagine you were to propose making a video that explains the Baunach Turkey paradox substantively. Right. Not, not showing around it, maybe not describing things in terms of um, like the group theoretic terminology that you usually see in the paper. [01:24:04] But the actual results that went into this idea of like breaking apart a sphere, proposing that to like a network TV station, saying, yeah, I'm going to do this in-depth talk of the binocs Haski paradox. I'm pretty sure it's going to reach 20 million people if they get out of here. Like no one cares about that. No one's interested in anything, even anywhere near that. But then you have Michael's quirky personality around it and just people that are actually hungry for that kind of depth. [01:24:30] Um. Then you don't need, like, the approval of some higher network, you can just do it and let the people speak for themselves. So I think, you know, if your father was to make something on plasma physics or if we were to have like under actualised robotics that undersaturated under actuated. Yes, not under actualise. [01:24:51] Plenty actualised under robotics and most robotics is under actualised. That's true. [01:24:58] So even if it's things that you might think are nesh, I bet you'll be surprised by how many people actually engage with it really deeply. [01:25:06] Although I just psychologically watching him, I can't speak for a lot of people speak for my dad. I think there's. There's a little bit of a skill gap, but I think that could be overcome, that's pretty big. None of us know how to make video when we start the first. If I made was terrible in a number of respects, like look at the earliest videos and in the YouTube channel, except for Captain Disillusion. And they're all like terrible versions of whatever they are now. [01:25:30] But the thing I've noticed, especially like with world experts, is it's the same thing that I'm sure you went through, which is like fear of embarrassment. Like they they definitely. It's it's the same reason, like I feel that any time I put out a video, I don't know if you still feel that, but like. I don't know, it's this imposter syndrome, like, who am I to talk about this and that? That's true for, like, even things that you've studied for, like, your whole life. [01:26:03] I don't know. It's scary to post stuff on YouTube. It is scary. [01:26:08] I honestly wish that more of the people who had that. Modesty to say, who am I to post this were the ones actually posting it? That's right. I mean, that's the honest problem is like a lot of the educational content is supposed to be people who, like, we're just starting to research it two weeks ago and are on a certain schedule and who maybe should think like who am I to explain it? Choose your favorite topic, quantum mechanics or something. [01:26:34] Um, and the people who have the self-awareness to not post are probably the people also best positioned to give a good, honest explanation of it. [01:26:44] That's why there's a lot of value in a channel like no file where they basically trap a really smart person and force them to explain stuff on a sheet of paper. [01:26:55] So but of course, that's not scalable as a single channel. If they if there's anything beautiful that could be done as people take it in their own hands, educators, which is again circling back, I do think the pandemic will serve to force a lot of people's hands. [01:27:11] You're going to be making online content anyway. It's happening, right? Just hit that publish button and see how it goes. Yeah, see, how goes the cool thing about YouTube is it might not go for a while, but like 10 years later, right? [01:27:26] Yeah, it'll be like this. The thing where people don't understand with YouTube, at least for now, at least that's my. Hope with it is it's a leg, it's it's literally better than publishing a book in terms of the legacy, it will live for a long, long time. Of course, it's one of the things I mentioned Joe Rogan before. It's kind of there's a sad thing because I'm a fan. He's moving to Spotify. Yeah, yeah, nine digit numbers will do that to you, but he doesn't really that he's one a person that doesn't actually care that much about money, like having talked to him. [01:28:06] It wasn't because of money. It's because he legitimately thinks that they're going to do like a better job. [01:28:16] So they're so from his perspective, YouTube, you have to understand where they're coming from. [01:28:21] YouTube has been cracking down on people who they you know, Joe Rogan talks to Alex Jones and conspiracy theories. And YouTube is really I care for that kind of stuff. And that's not a good feeling. Like and Joe didn't doesn't feel like YouTube was on his side. You know, he's often has videos that they don't put in trending that like are obviously should be in trending because they're nervous about like, you know, if this is this is this content going to, you know, upset people, all that kind of stuff have misinformation. [01:28:58] And that's not a good place for a person to be in. Spotify is going we're never going to censor you. We're never going to do that. But the reason I bring that up, whatever you think about that, I personally think that's bullshit because podcasting should be free and not constrained to a platform as pirate radio. What the hell? You can't as much as I love Spotify, you can't just you can't put fences around it. But anyway, the reason I bring that up is Joe's going to remove his entire library from YouTube. [01:29:31] Whoa. Really? That's going to do his full length. The clips are going to stay with the full length. Videos are all I mean, made private or deleted as part of the deal. And like that's the first time where I was like, oh, YouTube videos might not live forever. Like things you find like, OK, so this is why I need a typeface or something where it's like if there's a content link. I familiar with the system at all. [01:29:56] Like right now if you have a URL that points to a server, there's like a system where the address points to content and then it's like distributed. So you can't actually delete what's at that address because it's its content addressed. And as long as there's someone on the network who hosts it, it's always accessible at the address that it once was. But I mean, that raises a question. I'm not going to put you on the spot, but like somebody like Visa's, right? [01:30:19] Spotify comes along and gives him, let's say, one hundred billion dollars, OK, let's say some crazy number and then we'll remove it from YouTube. Right. It's maybe. [01:30:32] I don't know, for some reason, I thought YouTube is forever, I don't think it will be I mean, you know, another variant of this might take is like that, you know, you fast forward 50 years and, you know, Google or Alphabet isn't the company that it once was. And it's kind of struggling to make ends meet. And, you know, it's been supplanted by the whoever wins on the R game or whatever it might be. [01:30:56] And then they're like, you know, all of these videos that we're hosting are pretty costly. So we're just we're going to start deleting the ones that aren't watched that much and tell people to, like, try to back them up on their own or whatever it is, or even if it does exist in some form forever. [01:31:11] It's like if people are not habituated to watching YouTube in 50 years, they're watching something else, which seems pretty likely like it would be shocking if YouTube remained as popular as it is now indefinitely into the future. So it won't be forever. Makes me sad still, but because it's such a nice it's just like you said of the canonical videos, sorry I didn't have to, you know, usually get one minute on the on the thing and then talk to him about permanence. [01:31:39] I think you would have a good conversation. Who's that. So he's the one that founded this thing called epiphytes that I'm talking about. And if you have him talk about basically what you're describing, like, oh, it's sad that this isn't forever, then you'll get some articulate quantification around it. Yeah, it's like been pretty well thought through. [01:31:56] But yeah, I do see YouTube, just like you said, as a as a place like what your channel creates, which is like a set of canonical videos on a topic like others could create videos on that topic as well. But as a collection it creates a nice set of places to go. If you're curious about a particular topic, and it seems like coronaviruses, a nice opportunity to put that knowledge out there in the world at MIT and beyond. [01:32:27] I have to talk to you a little bit about machine learning and deep learning and so on. Again, we talked about last time you have a set of beautiful videos on your own that works. Let me ask you first, what is the most beautiful aspect of neural networks and machine learning to you, like for making those videos from watching how the field is evolving? [01:32:52] Is there something mathematically or an applied sense just beautiful to you about them? Well, I think what I would go to the layered structure and how you can have would feel like qualitatively distinct things happening going from one layer to another, but that are following the same mathematical rule. Because you look at as a piece of math, it's like you got a non-linearity and then you've got a matrix multiplication. That's what's happening. And all these layers, um, but especially if you look at like some of the visualizations that, like Chris Olá has done with respect to, um, like convolutional nets that have been trained on image net, trying to say, what does this neuron do? [01:33:31] What do this does this family of neurons do? What you can see is that the ones closer to the input side are picking up on very low level ideas like the texture. Right. And then as you get further back, you have higher level ideas like what is the where the eyes in this picture and then how do the eyes form like an animal? Is this animal a cat or a dog or a deer? You have this series of qualitatively different things happening, even though it's the same piece of math on each one. [01:33:56] So that's a pretty beautiful idea that you can have, like a generalisable object that runs through the layers of abstraction, which in some sense constitute intelligence, is having those many different layers of an understanding to something from abstractions in an automated way. [01:34:14] Exactly. It's automated abstracting, which I mean, that just feels very powerful. And the idea that it can be so simply mathematically represented, I mean, it's kind of like modern animal research seems a little bit like you do a bunch of ad hoc things. Then you decide which one worked and then you retrospectively come up with the mathematical reason that it always had to work. Um, but, you know, who cares how you came to it when you have, like, that elegant piece of math? [01:34:37] It's hard not to just smile seeing it work in action. [01:34:41] Well, and when you talked about topology before, one of the really interesting things is a. That's beginning to be investigated under kind of the fields of like science and deep learning, which is like the craziness of the surface that is trying to be optimized in neural networks. I mean, the the amount of local minima, local optima there is in these services and somehow a dumb gradient descent algorithm is able to find really good solutions. That's like that's really surprising. [01:35:15] Well, so on the one hand it is. But also it's like not it's not terribly surprising that you have these interesting points that exist when you make your space so high dimensional, like three. What did it have, 175 billion parameters. So it doesn't feel as mesmerizing to think about? Oh, there's some surface of intelligent behavior in this crazy high dimensional space. Like, there's so many parameters that, of course. But what's more interesting is like how how is it that you're able to efficiently get there, which is maybe what you're describing, that something as dumb as gradient descent does it? [01:35:50] But like the the reason the gradient descent works well with neural networks and not just choose however you want to parametrized the space and then apply gradient descent to it, is that layered structure lets you decompose the derivative in a way that makes it computationally feasible? [01:36:03] Um, yeah, it's just that, that there's so many good solutions, probably infinitely, infinitely many good solutions. Not best solutions, but good solutions. That's that's what's interesting. It's similar to a Stephen Wolfram as this idea of like. [01:36:22] The if you just look at all space of computations, of all space, of basically algorithms, that you'd be surprised how many of them are actually intelligent, like if you just randomly pick from the bucket, that's surprising. [01:36:36] We tend to think like a tiny, tiny minority of them would be intelligent. But his sense is like it seems weirdly easy to find computations that do something interesting. Well, OK. [01:36:50] Is that from like a Kamogawa Kamogawa of complexity standpoint, almost everything will be interesting. What's fascinating is to find the stuff that's describable with low information, but still does interesting things like one fine example of this, you know, Shannons, noisy coding in Theorem, Noisey coding theorem and information theory that basically says if I want to send some bits to you, maybe some of them are going to get flipped. There's some noise along the channel. I can come up with some way of coding it. [01:37:21] That's resilient to that noise. That's very good. And then he quantitatively describes a very good is what's funny about how he proves the existence of good error correction codes is rather than saying like here's how to construct it or even like a sensible nonconstructive proof the nature of his non-constructive proof is to say if we chose a random encoding, it would be almost at the limit, which is weird because then it took decades for people to actually find any that were anywhere close to the limit. [01:37:49] And what his proof was saying is choose a random one. And it's like the best kind of encoding you'll ever find. But what's. What that tells us is that sometimes when you choose a random element from this ungodly huge set, that's a very different task from finding an efficient way to actively describe it, because in that case, the random element to actually implement it as a bit of code, you would just have this huge table of, like, telling you how to encode one thing into another that's totally, computationally infeasible. [01:38:17] So on the side of like, how many possible programs are interesting in some way, it's like, well, tons of them. [01:38:23] But the much, much more delicate question is when you can have a low information description of something that still becomes interesting and thereby this kind of gives you a blueprint for how to engineer that kind of thing right now. [01:38:36] Yes, there is another good instance. There was like, yeah, a ton of things are hard to describe, but how do you have ones that have a simple set of governing equations that remain like arbitrarily hard to describe? [01:38:47] Well, let me ask you, you mentioned DPG three. It's interesting to ask, what are your thoughts about the recently released open AGP T3 model that I believe is already trying to learn how to communicate like Grant's Anderson? [01:39:04] You know, I think I got an email a day or two ago about someone who wanted to try to use D3 with Manam where you would, like, give it a high level description of something, and then it'll automatically create the mathematical animation, like trying to put me out of a job here. [01:39:22] I mean, it probably won't put you out of a job, but to create something visually beautiful for sure, I would be surprised if that worked, as stated. But maybe there's like variants of it like that you can get to. I mean, like a lot of those demos. [01:39:34] It's interesting. I think there's a lot of failed experiments. Depending on how you prime the thing, you're going to have a lot of failed. I mean, certainly with code programs synthesis, most of it won't even run. But eventually, I think if you if you're if you pick the right examples, you'll be able to generate something cool. [01:39:55] And I think even that's good enough, even though if if it's if you're being very selective, it's still cool that something can be generated. [01:40:03] Yeah, that's huge value. I mean, think of the writing process sometimes as a big part of it is just getting a bunch of stuff on the page and then you can decide what to whittle down to. So if it can be used in like a man machine symbiosis where it's just giving you a SPU of potential ideas that then you can refine down like it's serving as the generator and then the Human Services, the refiner, that seems like a pretty powerful dynamic. [01:40:27] Yeah. [01:40:27] Have you have you gotten a chance to see any of the demos like on Twitter? Is there a favorite you've seen or. Oh my absolute favorite. Yeah. So Tim Blay, who runs a channel called Acappella Science, he was like tweeting a bunch about playing with it. And so so Deepthi was trained on the Internet from before covid. So so in a sense, it doesn't know about the coronavirus. So what he seeded it with was just a short description about like a novel virus emerges in Wuhan, China, and starts to spread around the globe. [01:40:58] What follows is a month by month description of what happens January Kotlin. Right? That's what he said. So then what it generates is like January than a paragraph of description, February and such. And it's the funniest thing you'll ever read because it predicts a zombie apocalypse, which of course it would, because it's drained on like the into the internal mysteries. [01:41:19] But what you see unfolding is a description of covid-19 if it were a zombie apocalypse and like the early aspects of it, are kind of shockingly in line with what's reasonable and then it gets out so quickly. [01:41:31] And the other flipside of that is I wouldn't be surprised if it's onto something at some point here when, you know, 2020 has been full of surprises, like we might all be in like this crazy militarized zone, as it predicts, just a couple of months off. [01:41:48] Yeah, I think there's definitely an interesting tool of storytelling. It has struggled with mathematics, which is interesting or just even numbers. It's able to it's not able to generate like patterns. [01:42:02] You know, like you give it in like five digit numbers and it's not able to figure out the sequence, you know, or like I didn't look in too much, but I'm talking about, like, sequences like the Fibonacci numbers to see how far can go because obviously it's leveraging stuff from the Internet and it starts to lose it. But it is also cool that I've seen it able to generate some interesting patterns that are mathematically correct. [01:42:29] Yeah, I honestly haven't dug into like what's going on within it in a way that I can speak intelligently to. I guess it doesn't surprise me that it's bad in numerical patterns because. I mean, maybe I should be more impressed with it, but like that requires having a weird combination of intuitive and and formulaic worldview. So you're not just going off of intuition when you see Fibonacci numbers, you're not saying, like intuitively, what do I think will follow the 13? [01:42:58] Like, I've seen patterns a lot where like 13 there, followed by 20 ones. Instead, it's that like the way you're starting to see a shape of things is by knowing what hypotheses to test where you're saying, oh, maybe it's generated based on the previous terms or maybe it's generated based on like multiplying by a constant or whatever it is you like have a bunch of different hypotheses and your intuitions are around those hypotheses, but you still need to actively test it. [01:43:20] Um, and it seems like theory is extremely good at like that sort of pattern matching recognition that usually is very hard for computers. That is what humans get good at through expertise and exposure to lots of things. It's why it's good to learn from as many examples as you can rather than just from the definitions. It's to get that level of intuition, but to actually concretize it into a piece of math, you do need to like test your hypotheses and if not, prove it, um, like have an actual explanation for what's going on, not just a pattern that you've seen. [01:43:54] And but then the flip side, to play devil's advocate, that's a very kind of probably correct intuitive understanding of just like we said, a few a few layers creating abstractions, but it's been able to form. [01:44:10] Something that looks like a compression of the data that it's seen, that looks awfully a lot like it understands what the heck is talking about? [01:44:19] Well, I think a lot of understanding is like I don't mean to denigrate pattern recognition. Pattern recognition is most of understanding and it's super important and it's super hard. And so, like, when is demonstrating this kind of real understanding, compressing down some data like that, that might be pattern recognition at its finest? My only point would be that like what differentiates math, I think to a large extent, is that the pattern recognition isn't sufficient and that the kind of patterns that you're recognizing are not like the end goals, but instead they're they are the little bits and paths that get you to the end goal. [01:44:56] That's certainly true for mathematics in general. And it's an interesting question. If that might for certain kinds of series of numbers, it might not be true like you might, because it's a basic, you know, like Talercio like certain kinds of series, it feels like. Compressing the Internet is is enough to figure out because those patterns in some form appear in the text somewhere. [01:45:23] Well, I mean, there's all sorts of wonderful examples of false patterns in math where one of the earliest videos I put on the channel was talking about the extent of dividing a circle up using these chords. And you see this pattern of one, two, four, eight, 16. It's like, oh, it's pretty easy to see what that pattern is. It's powers of two. We've seen it a million times, but it's not powers of two. [01:45:42] The next term is thirty one. And so it's like almost a power of two, but it's a little bit shy and there's there's actually a very good explanation for what's going on. Um, but I think it's a good test of whether you're thinking clearly about mechanistic explanations of things, how quickly you jump to thinking it must be powers of two, because the problem itself, there's really no no good way to I mean, there can't be a good way to think about it as like doubling a set, because ultimately it doesn't. [01:46:10] But even before it starts to, it's not something that screams out as being a troubling phenomenon. So at best, if it did turn out to be powers of two, it would have only been so very subtly. And I think the difference between, like, you know, a math student making the mistake in a mathematician who's experienced seeing that kind of pattern is that they they'll have a sense from what the problem itself is, whether the pattern that they're observing is reasonable and how to test it. [01:46:33] And like. I would just be very impressed if there was any algorithm that was actively accomplishing that goal. Yeah, like a learning based algorithm. [01:46:45] Like a little scientist, I guess, basically. Yeah. It's a it's a fascinating thought because GBG, three of these language models already accomplishing way more than I've expected. So I'm learning not to doubt, but we'll get there. [01:46:59] Yeah, I, I'm not saying I'd be impressed, but like surprised, like I'll be impressed, but I think we'll get there on, um, algorithms doing math like that. [01:47:09] So one of the amazing things you've done for the world is to some degree, open sourcing, the tooling that you use to make your videos with Manam this Python library. Now, it's quickly evolving because I think you're inventing new things every time you make a video. In fact, I wanted I've been working on playing around with something I wanted to do, like an ode to blue and Brown. Like I love playing Hendrix. I wanted to do like a cover of a concept. [01:47:41] I wanted to visualize and use Manam. And I saw that you had like a little piece of code on like Mobius strip and try to do some cool things with spinning a Mobius strip, like continue. [01:47:55] Twisting it, I guess, is the term, and it was easier to. It was tough, so I haven't figured it out yet. Well, so I guess the question I want to ask is so many people love it that you've put that out there. They want to do the same thing as I do with Hendryx. I want to cover it. They want to explain an idea using the tool, including Russ. How would you recommend they try to. [01:48:18] I'm very sorry. They try to go they try to go buy about it. Well, and what kind of choices should they choose to be most effective? That I can answer. So I always feel guilty if this comes up because I think of it like the scrapie tool. That's like a math teacher who put together some code. People asked what it was, so they made it open source and they kept scrapping it together. And there's a lot like a lot of things about it that make it harder to work with. [01:48:46] And it needs to be that are a function of like me not being a software engineer. Um, I've put some work this year trying to, like, make it better and more flexible. Um, that is still just kind of like a work in process. Um, one thing I would love to do is just get my act together about properly integrating with what the community wants to work with and like what stuff I work on and making that not like deviate and just like actually fostering that community in a way that I've I've been shamefully neglectful of. [01:49:18] So I'm just always guilty if it comes up. So let's put that guilt aside just then. [01:49:22] Like I then I'll pretend like it isn't terrible for someone like Russ. Um, I think step one is like make sure that what you're intimating should be done so programmatically because a lot of things maybe shouldn't, um. Like if you're just making a quick graph of something, if it's a graphical intuition that maybe has a little motion to it, use decimals, use graph or use jojoba, use Mathematica, certain things that are like really oriented around jojoba is kind of cool. [01:49:46] I did something super amazing. You can get very, very far with it. And in a lot of ways, like it would make more sense for some stuff that I do to just do angioedema. But I kind of have the cycle of liking to try to improve and by doing videos and such, so do as I say, not as I do. [01:50:02] The original like thought I had and making Menom was that there's so many different ways of representing functions other than graphs, um, in particular things like transformation's, like use movement over time to communicate relationships between inputs and outputs instead of like X direction in my direction or like vector fields or things like that. So I wanted something that was flexible enough that you didn't feel constrained into a graphical environment. Um, by graphical I mean like graphs with the like X coordinate like why coordinate kind of stuff. [01:50:32] But also make sure that. You're taking advantage of the fact that it's programatic, you have loop's, you have conditionals, you have abstraction, if any of those are like well fit for what you want to teach to, you know, have a scene type that you tweak a little bit based on parameters or to have conditionals so that things can go one way or another or loops, so that you can create these things of like arbitrarily increasing complexity. That's the stuff that's like meant to be animated programmatically. [01:50:56] If it's just like writing some text on the screen or shifting around objects or something like that, um, things like that, you should probably just use Keano. [01:51:04] Right. You'd be a lot simpler. [01:51:06] So, uh, try to find a workflow that distills down that which should be programatic into Menom and that which doesn't need to be into like other domains. Again, do as I say, not as I do. [01:51:18] I mean, Python is an integral part of it. And just for the fun of it, I may ask what what's your most and least favorite aspects of Python? [01:51:28] Most and least I mean, I love that it's like object oriented and functional. I guess that you can kind of like get both of those, um, uh, benefits for how you structure things. So if you would just want to quickly whip something together, the functional aspects are nice. It's your primary language, like for programmatically generating stuff. Yeah, it's home for me. It's helpful. Yeah. Sometimes I travel by home that it's home. [01:51:53] Uh, I mean the biggest disadvantage is that it's slow. So when you're doing computationally intensive things, either you have to think about it more than you should, how to make it efficient or, uh, just like takes long. Do you run into that at all, like with your work? [01:52:06] Well, so certainly Old Menom is like way slower than it needs to be because of, uh, how it renders things on the back end is like kind of absurd. I've rewritten things such that it's all done with like shaders in such a way that it should be just like Leive and actually like interactive while you're coding it, if you want to to you have like a 3D scene, you can move around. You can have, um, elements respond to where your mouth is or things. [01:52:31] That's not something that user of a video is going to get to experience because there's just a play button and a pause button. But while you're developing, that can be nice. Um, so it's gotten better in speed in that sense. But that's basically because the hard work is being done in the language. That's not Python but Glassell. Right. [01:52:46] Um, but yeah, there are some times when it's like a um, there's just a lot of data that goes into the object that I want to animate that. Then it just like Python is slow. Well, let me ask quickly ask what do you think about the Walrus operator if you're familiar with it all? The reason it's interesting, there's a new operator in Python, three point eight. [01:53:06] I find it psychologically interesting because the toxicity over it led to resign, to step down is actually true, or was it like there's a bunch of surrounding things that also was it actually the wall was operated that while it was it was tax, it was an accumulation of toxicity. [01:53:23] But that was the the most that was the most toxic one. Like the discussion. That's the most number of Python core developers that were opposed to Guido's decision. Hmm. He didn't particularly, I don't think cared about it either way. He just thought it was a good idea to approve it. And like the structure of the idea of a bedfellows, like you listen. Ever hear of radio? You make a decision and you move forward, and he didn't like the negativity that burden him after that, people like some parts of the benevolent dictator for life mantra. [01:53:57] But once the dictator does things different than you want, suddenly a dictatorship doesn't seem so great. [01:54:02] Yeah, I mean, they still like that. He just couldn't because he truly is the be in the benevolent. He's he really is a nice guy. I mean, and I think he can't it's a lot of toxicity is difficult. It's a difficult job. That's why Linus Torvalds is perhaps the way he is. You have to have a thick skin to fight off, fight off the warring masses. It's kind of surprising to me how many people can, like, threaten to murder each other over whether we should have Brace's or not or whether I like. [01:54:31] It's incredible. [01:54:32] Yeah. I mean, that's my knee jerk reaction to the Wall Street is like I don't actually care that much either way. I'm not going to get really passionate. My my initial reaction was like, yeah, this seems to make things more confusing to read, but then again, so does list comprehension until you're used to it. So like if you use for it, great, if not great. But like let's just all calm down about our spaces versus Tab's debates here in like feature. [01:54:55] Yeah. To me it just represents the the value of great leadership, even in open source communities. [01:55:01] Doesn't represent that if he steps down as a leader while he fought for it, he got it passed I guess. [01:55:07] But I guess I could represent multiple things too. [01:55:10] It can represent like a failed dictatorship or represents a lot of things. But to me, great leaders take risks even if it. Even if it's a mistake at the end, like you have to make decisions. The thing is this world won't go anywhere if you can't if whenever there's a divisive thing, you wait until the division is no longer there. That's the paralysis we experienced with Congress and political systems. It's good to be slow when there's indecision, when there's people disagree. [01:55:45] It's good to take your time. But like at a certain point, it results in paralysis and you just have to make a decision. The background of the site, whether it's yellow, blue or red, can cause people to go to war over other, which I've seen this with design. People are very touchy on color color choices. At the end of the day, just make a decision and go with it. [01:56:06] I think that that's what the wireless operator represents to me, is they represents the fighter pilot instinct of like quick action is more important than, uh, than just carrying everybody out. And really they get through it because that's going to lead to paralysis. [01:56:23] Yeah, like, if that's the actual case that, you know, it's something we're consciously hearing people's, uh, disagreement, disagreeing with that disagreement and saying he wants to move forward anyway. Uh, yeah, that's an admirable aspect of leadership. So we don't have much time, but I want to ask just because it's some beautiful mathematics involved, 20, 20 bodies, a couple of in the physics world theories of everything. Eric Wilstein, kind of I mean, he's been working for probably decades, but he put out this idea of geometric unity or started sort of publicly thinking and talking about it more. [01:57:02] Stephen Wolfram put out his physics project, which is kind of the type of graph view of a theory of everything. [01:57:10] Do you find interesting, beautiful things to these theories of everything? What do you think about the physics world and sort of the beautiful, interesting, insightful mathematics in that world, whether we're talking about quantum mechanics, which you touched on a bunch of your videos, a little bit quaternions like just the mathematics involved or the general relativity, which is more about surfaces and topology, all that stuff. [01:57:36] Well, I think as far as like popularized science is concerned, people are more interested in theories of everything than they should be like, because the problem is whether we're talking about trying to make sense of why Einstein's lectures or Wolfram's project or let's just say like listening to Whiton talk about string theory, whatever proposed path to a theory of everything, um, you're not actually going to understand it. Some physicists will. But like, do you just not actually going to understand the substance of what they're saying? [01:58:06] What I think is way, way more productive is to let yourself get really interested in the phenomena that are still deep, but which you have a chance of understanding, because the path to getting to like even understanding what questions these theories of everything are trying to answer involves like walking down that. I mean, I was watching a video before I came here about from Steve Moore talking about why sugar polarizes light in a certain way. [01:58:29] So fascinating. Like really, really interesting. It's not like this novel theory of everything type thing, but to understand what's going on there really requires digging in depth to certain ideas. And if you let yourself think past what the video tells you about what the circularly polarised light mean and things like that, it actually would get you to a pretty good appreciation of like two state states and quantum systems in a way that just trying to read about like what's the what are the hard parts about resolving quantum field theories with general relativity is never going to get you. [01:59:01] So as far as popularizing science is concerned, like. The audience should be less interested than they are in the use of everything, the popularizers should be less emphatic than are about that for like actual practicing physicists, I might be the case. [01:59:17] Maybe more people should think about fundamental questions, but it's difficult to create like a three blue one brown video on the theory of everything. So basically, we should really try to find the beauty and mathematics of physics by looking at concepts that are like within reach. [01:59:35] Yeah, I think that's super important. I mean, so you see this in math, too, with the big unsolved problems. So like the millennium problems remain hypothesis. Have you ever done a video on Fermat's last theorem? I have. Not yet, no. But if I did, do you know what I would do? I would talk about proving Fermat's last theorem in the specific case of an equals three. Yeah, that's still accessible. [01:59:58] Yes, actually barely. Mythology might be able to do a like a great job on this. He does a good job of taking stuff that's barely accessible in making it. But the the core ideas of proving it for any three are hard. But they do get you real ideas about Algebraic No3. It involves looking at a number of field that it lives in the complex plane. It looks like a hexagonal lattice and you start asking questions about factoring numbers in the Texarkana lattice. [02:00:23] So it takes a while. But I've talked about this sort of like lattice arithmetic in other contexts and you can get to a understanding of that. And the things that make Fermat's last theorem hard are actually quite deep. Um, and so the cases that we can solve it for, it's like you can get these broad sweeps based on some hard but like accessible, um, bits of no theory. But before you can even understand why the general cases, as hard as it is, you have to walk through those. [02:00:50] And so any other attempt to describe it would just end up being like shallow and not really productive for the viewers time. I think the same goes for most like unsolved problem type things where I think, you know, as a kid, I was actually very inspired by the twin prime conjecture that, like, totally sucked me in is this thing that was understandable. I kind of had this dream like, oh, maybe I'll be the one to prove the twin prime conjecture and new math that I would learn would be like viewed through this lens of like, oh, maybe I can apply it to that in some way. [02:01:18] But you sort of mature to a point where you realize. You should spend your brain cycles on problems that you will see resolved because then you're going to grow to see what it feels like for these things to be resolved rather than spending your brain cycles on something where it's not it's not going to pan out. And the people who do make progress towards these things, like James Maynard, is a great example here of like young creative mathematician who, like, pushes in the direction of things like the twin prime conjecture rather than hitting that head on. [02:01:49] Just see all the interesting questions that are hard for similar reasons, but become more tractable and let themselves really engage with those. [02:01:55] Um, so I think people should get in that habit. I think the popularization of physics should encourage that habit through things like the physics of simple everyday phenomena because it can get quite deep and. Yeah, I think, you know, I've heard a lot of the interest that people send me messages asking to explain Weinstein's thing or I think to explain Wolfram's thing, one, I don't understand them, but more importantly, it's too big a bite and you shouldn't be interested in those. [02:02:24] Right. The giant sort of ball of interesting ideas. There's probably a million of interesting ideas in there that individually could be explored effectively. [02:02:34] And to be clear, you should be interested in fundamental questions. I think that's a good habit to ask what the fundamentals of things are, but I think it takes a lot of steps to certainly you shouldn't be trying to ask unless you actually understand quantum field theory and you actually understand general relativity. That's the cool thing about your videos. People haven't done mathematics. Like if you really give a time watching a couple of times and like try to try to reason about it, you can actually understand the concept that's being explained. [02:03:02] And it's not a coincidence that the things I'm describing aren't like the most up to date progress on the Riemann Hypothesis cousins or like there's context in which the analogue of the human hypothesis has been solved and more discrete feeling finite settings that are more well behaved. I'm not describing that because it just takes a ton to get there. And instead, I think it'll be like productive to have an actual understanding of something that can you can pack into twenty minutes. [02:03:29] I think that's beautifully put. Ultimately, that's where like the most satisfying thing when you really understand. Yeah, really understand build the habit of feeling what it's like to actually come to resolution. Yeah, yeah. [02:03:43] As opposed to which it can also be enjoyable, but just being in awe of the fact that you don't understand anything. [02:03:50] Yeah, but like, I don't know, maybe people get entertainment out of that, but it's not as fulfilling as understanding you won't grow. [02:03:59] Yeah. And but also just the fulfilling and it really does feel good when you first don't understand something and then you do. That's a beautiful feeling. Let me ask you one last last time it got awkward and weird about a fear of mortality, which you made fun of me of. But let me ask you on the the other absurd question is, what do you think is the meaning of our life, of meaning of life? [02:04:24] I'm sorry if I made fun of you about which. No, you didn't. I'm just joking. It is great. [02:04:30] I don't think life has a meaning. I think like meaning. I don't understand the question. I think meaning is something that's ascribed to stuff that's created with purpose. There's a meaning to like this water bottle label and that someone created it with a purpose of conveying meaning. And there was like one consciousness that wanted to get its ideas into another consciousness. Most things don't have that property. It's a little bit like if I asked you, like, what is the height? [02:04:57] All right, so it's all relative. You'd be like the height of what you can't ask, what is the height without an object? You can't ask what is the meaning of life without, like, an intent for consciousness putting it? Well, yeah, I guess I'm revealing I'm not very religious. [02:05:11] But, you know, the mathematics of everything seems kind of beautiful. It seems like it seems like there's some kind of structure. Relative to which, I mean, you could calculate the height well, but what I'm saying is I don't understand the question, what is the meaning of life in that I think people might be asking something very real. I don't understand what they're asking. Are they asking like, why does life exist? Like, how did it come about? [02:05:34] What are the natural laws? Are they asking as I'm making decisions day by day for what should I do? What is the guiding light that inspires? Like what should I do? I think that's what people are kind of asking. [02:05:44] But also like why the thing that gives you joy about education, about mathematics, what the hell is that like? [02:05:54] What interactions with other people, interactions with like minded people, I think is the meaning of, in that sense, bringing others joy. [02:06:02] Essentially, like in something you've created, it connects with others somehow and the same and the vice versa. [02:06:10] But I think that that is what when we use the word meaning to mean, like you sort of filled with a sense of happiness and energy to create more things. Like I have so much meaning taken from this. [02:06:20] Like that. Yeah. That's what fuels fuels my pump at least. [02:06:23] So a life alone on a desert island be kind of meaningless if you want to be alone together with someone. [02:06:30] I think we're all alone together. I think there's no better way to end it. You've been first time we talked as amazing. Again, it's a huge honor that you make time for me. I appreciate talking with you. Thanks for an awesome. Thanks for listening to this conversation with Grant Sanderson and thank you to our sponsors, Dollar Shave Club Doda and Cash App, click the sponsored links in the description to get a discount and to support this podcast. [02:06:56] If you enjoy this thing, subscribe on YouTube, review it with five stars and have a podcast. Follow on Spotify, support on Patron or connect with me on Twitter. Àlex Friedemann. And now let me leave you some words from Richard Feynman. I have a friend who's an artist and is sometimes taking a view which I don't agree with very well. He'll hold up a flower and say, look how beautiful it is. And I'll agree. Then he says, I, as an artist can see how beautiful this is. [02:07:25] But you as a scientist take this all apart and it becomes a dull thing. And I think he's kind of nutty. First of all, the beauty that he sees is available to other people and to me, too, I believe, although I may not be quite as refined aesthetically as he is, I can appreciate the beauty of a flower. [02:07:44] At the same time, I see much more about the flower than he sees. I can imagine the cells in there, the complicated actions inside, which also have a beauty. I mean, it's not just beauty at this dimension, that one centimeter. There's also beauty in smaller dimensions, the inner structure, also the processes, the fact that the colors in the flower evolved in order to attract insects to pollinate it is interesting. It means that insects can see the color. [02:08:11] It adds a question. Does this aesthetic sense also exist in the lower forms? Why is it aesthetic? All kinds of interesting questions which the science knowledge only adds to the excitement, the mystery and the all of a flower. It only adds. I don't understand how it subtracts. Thank you for listening and hope to see you next time.

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