Category Theory in Context
by Emily Riehl · first published 2016
50% recommend44% neutral6% critical
Why HN recommends it
A strong introduction to category theory for readers with an undergraduate math background, and a good next step after gentler introductions like Fong and Spivak's. Its Dover edition is also affordable.
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…wonderful to just curl up with a book and a cup of tea and let time pass you by as you ... learn the considered thought of others! This is civilised! Normally I'd recommend history but around these parts Category Theory in Context by Emily Riehl is probably acceptable :) About re-reading, especially textbooks: it takes time and trouble to appreciate the difficult and often esoteric ideas represented in a text and understand the…
on “My lizard brain is no match for infinite scroll” ↗…Invitation to Applied Category Theory: Seven Sketches in Compositionality” [1] also introduces category-theoretic ideas using partial orders. Edit: After the Fong & Spivak book, the book by Emily Riehl, "Category Theory in Context" is an excellent next step, although it requires some mathematical maturity. [1]: https://arxiv.org/abs/1803.05316
on “Category Theory: Orders” ↗What book will suit you depends on your background. If you have a solid background in math, say an undergraduate degree in math, my favorite book is Emily Riehl's Category Theory in Context [1] (the "context" in the title refers to a background in math). If you don't know that much math, I'd recommend Tom Leinster's Basic Category Theory [2] or Steve Awodey's Category Theory [3] (particularly…
on “Emily Riehl is rewriting the foundations of higher category theory” ↗Riehl's "Category Theory in Context" is great. It's one of those books where every page really takes a couple hours to fully absorb. It pairs well with Milewski's "Category Theory for Programmers" [1] series, which is comparatively lighter…
on “Ask HN: Technical Summer Reading List” ↗…Introduction to Categories - Lawvere Category Theory for Programmers - Milewski (if you like functional programming) Programming with Categories - Fong, Milewski, Spivak (if you like functional programming) Category Theory in Context - Riehl There are a few others by Spivak which you may like. If you don't know category theory whatsoever then I like Southwell the best (pair them up with his youtube videos). Eugenia Cheng also has…
on “Physics Student Earns PhD at Age 89” ↗…0. I would suggest not trying to dive into this prior to at least encountering fields, groups and rings because it's good to have both the traditional and modern (read: categorical) contexts. Also try Category Theory in Context, by Riehl. 7. Complex Analysis Complex Analysis, by Ahlfors. This is an excellent and concise text. You can theoretically approach this before real analysis, but I wouldn't recommend that. Also try…
on “Ask HN: Mathematicians, what textbooks are best for learning these math topics?” ↗For a more advanced book: Category Theory in Context by Emily Riehl
on “Applied Category Theory Course (2018)” ↗I went through her book "Category Theory in Context" a few years ago and loved it! It's a great introduction to the field.
on “Emily Riehl is rewriting the foundations of higher category theory” ↗Category Theory in Context is such a great book. Kudos to Dover’s Aurora publishing arm for a great, original book at such a great price. Always love dover and adding additional new contents to the back catalogue of reprints is…
on “Category Theory: Orders” ↗…Working Mathematician on my own. I left mathematics soon after—with some regret—and haven’t kept up with the field. The interview with Emily Riehl and the introduction (which I read just now) to her book Category Theory in Context suggest that the field has made a lot of advances in the years since. I have a question for people who are familiar with recent developments. Forty years ago, the opinions of other math grad students…
on “Emily Riehl is rewriting the foundations of higher category theory” ↗…really help solidify things for me. Once I finish those, I'll see whether I want to go deeper into Topology or move to Complex Analysis or Differential Geometry. I also have a copy of Emily Riehl's Category Theory in Context. I've read some Category Theory before and have a basic grasp, but after reading a few pages of her book, I put it aside until I feel like I'm much more well versed in Topology (the content looks amazing…
on “Ask HN: Technical Summer Reading List” ↗There "Category Theory in Context" book by Emily Riehl is also freely available at https://golem.ph.utexas.edu/category/2016/11/category_theory... (I didn't read it yet)...
on “Basic Category Theory” ↗Yes, that book in particular. I have Emily Riehl's Category Theory in Context which was not immediately accessible to me at all. Joy of Abstraction aims to be an on-ramp to that.
on “Lisp as the Maxwell’s Equations of Software (2012)” ↗…theory, whose proof without invoking such theory is much less elegant and general’, you’ll find plenty in any area of mathematics that uses category theory. There’s a whole section of Emily Riehl’s book Category Theory In Context on ‘theorems in category theory’ (since it’s famously said that there are none — you’re certainly not the first to level such an accusation!).
on “From Sets to Categories (2023)” ↗…book published by another publisher, but Dover's Aurora series consists of modern original texts as opposed to their usual republications of classic out of print texts -- this is how Emily Riehl had her "Category Theory in Context" published
on “Online Book: Exploring Mathematics with Python” ↗