Came here to post this as well.. Here the link to the 2nd edition (it also has the first edition in the collection): http://link.springer.com/content/pdf/10.1

Came here to post this as well.. Here the link to the 2nd edition (it also has the first edition in the collection): http://link.springer.com/content/pdf/10.1007/978-1-4757-4721-8.pdf http://link.springer.com/content/pdf/10.1007/978-1-4757-4721... More on category theory --but more for a programmer's usecase-- here: https://www.quora.com/What-is-the-best-textbook-for-Category-theory https://www.quora.com/What-is-the-best-textbook-for-Category... And here: http://bartoszmilewski.com/2014/10/28/category-theory-for-programmers-the-preface/ http://bartoszmilewski.com/2014/10/28/category-theory-for-pr...