Category Theory in Life - Eugenia Cheng

Lambda World · 112.8K views · 2017-11-03 · 40:39

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Overview

Eugenia Cheng gives the opening keynote at Lambda World 2017, presenting category theory as very abstract algebra whose abstraction gives it broad applicability. She applies it to everyday questions including privilege and prejudice.

On Hacker News

HN recommends it as an accessible, gentle introduction that makes category theory feel approachable and shows its analogy-making power.

Recommended by 3 HN people across 3 months · HN mentions 2019–2022

Topics

Pure mathematics Functional programming Recreational & visual math

What people said

OracB7 · 2022-08 · Recommendation
Eugenia Cheng has some interesting and accessible videos, e.g.: [VIDEO] and in a similar vein I am enjoying her book: "How to Bake Pi". Getting more into the technical side of things, Bartosz Milewski has good lessons in this playlist: [LINK]
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gugagore · 2021-02 · Recommendation
There is an applied category theory course that is currently in the process of wrapping up: [LINK] The examples in the course offer a complementary entry point to category theory compared to an approach that leverages programmers' knowledge of functional programming. Personally, the more examples the better. I'm grateful to be able to rely on the example of a category as a collection of objects corresponding to types, and arrows between types corresponding to functions with that type signature, and arrow composition corresponding to function composition (and functors, and natural transformations, and ... corresponding to familiar concepts like polymorphic types, and map, and polymorphic functions and ...). I believe that many programmers can [come to] understand this one specific example of category theory objects, even if the words are unfamiliar. And there are so many more examples! There is a great pleasure in formalizing the analogies across different aspects of math and engineering. To get a flavor of and gentle introduction to the analogy-making power of category theory, I recommend this talk by Eugenia Cheng: [VIDEO]
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sunmao · 2019-04 · Recommendation
"But it’s hard to explain to people not steeped in the subject." I don't agree. Actually it can be understood relatively easily, if it's explained well: [VIDEO] [LINK]
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Sources

Video by Lambda World, played through YouTube.

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