Slightly off topic - at Lambda Conf right now, went to Spivak's 6 hour lecture on category theory. Whenever they post the videos, I'd recommend it. He's an exce

Slightly off topic - at Lambda Conf right now, went to Spivak's 6 hour lecture on category theory. Whenever they post the videos, I'd recommend it. He's an excellent instructor. Others mentioned that his textbook on category theory was also really good, but I can't confirm.