nLab Categories for the Working Mathematician


Category theory


This page compiles pointers related to:

which is a classical textbook on category theory.

The iconic title probably refers to the declared ambition of demonstrating the prevalence of examples of adjoint functors occurring throughout mathematics:

[p. 2:] “Adjoints, as we shall see, occur throughout mathematics.”

[p. 103:] “The multiple examples, here and elsewhere, of adjoint functors tend to show that adjoints occur almost everywhere in many branches of Mathematics. It is the thesis of this book that a systematic use of all these adjunctions illuminates and clarifies these subjects.”

See also:

and the list of category theory textbooks here.


The original edition has the following chapters:

The 2nd edition was published in 1997 with two additional chapters:

category: reference

Last revised on June 4, 2023 at 13:44:05. See the history of this page for a list of all contributions to it.