Applied Category Theory - The Emerging Science of Compositionality

An enjoyable 25-minute introductory talk: YOW! Lambda Jam 2019 - Ken Scambler - Applied Category Theory (slides)

What do programming, quantum physics, chemistry, neuroscience, systems biology, natural language parsing, causality, network theory, game theory, dynamical systems and database theory have in common?

As functional programmers, we know how useful category theory can be for our work - or perhaps how abstruse and distant it can seem. What is less well known is that applying category theory to the real world is an exciting field of study that has really taken off in just the last few years. It turns out that we share something big with other fields and industries - we want to make big things out of little things without everything going to hell! The key is compositionality, the central idea of category theory.

Previously: Seven Sketches in Compositionality: An Invitation to Applied Category Theory.

(via Brian McKenna)

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

you should blog more

you should blog more

Have to shave some yaks.

Have to shave some yaks.

Connecting the dots

Alas, so far at least this talk hasn't worked for me. Overall, I didn't pick up, from what he was saying, how to connect the things he was talking about to the basic mathematics of category theory. That aspect of the talk came across to me as (except for some trivial bits) too hand-wavy to see actual categories in it. Admittedly, I don't consider myself to grasp a mathematical concept until I intuitively grasp it, which is quite a high bar for abstract mathematics; but if I hold myself to that standard when explaining math to others, why shouldn't I ask as much of others when they're explaining stuff to me?

His first line set my teeth on edge: "Category theory. Some of you might know it as a valuable part of your functional programmers' toolkits, others might know it as scary nonsense that some people just won't shut up about." I've noticed some people condescendingly assume that failure to love category-based pure-functional programming can only be explained by fear of mathematics. Granted, the talk doesn't hinge on that; but it did start things off on the wrong foot, for me.

Not worth 20 minutes

Granted, I just skimmed, but the ideas in the talk seemed pretty shallow. I remain skeptical of the importance of category theory for programmers in general.

Introductory talk

This is talk intended as an introduction and invitation for people who might have never looked at category theory before. As such it qualifies as a success: it has made at least one person who hadn't looked into category theory before want to learn more about it.


That's a valid measure of success. It's also fair game to ask how it could be improved.