Lars, I would guess that you will get more advice than you can use. Here is my nickel's worth. The matter of coherence is wide open. There is a paper of Yanofsky accepted for publication in JPAA which investigates higher dimensional categories with no coherence assumptions at all -- this coming after a lot of work on weakened coherence. Benabou's basic point was that naturally arising 2-dimensional categories are not quite 2-categories and don't seem to suffer from it. Avoid getting knotted in coherence questions, especially in 1999. _____________________________ John R. Isbell ji2@buffalo.edu or ji2@acsu.buffalo.edu Homepage: www.unipissing.ca/topology/z/a/a/a/05.htm _________________________________________________ | | | Der Mensch ist nur da ganz Mensch, wo er spielt. | | | | -- Friedrich Schiller | |_________________________________________________ | On Sat, 30 Jan 1999, Lars Lindqvist wrote:

Hi,

I am looking for advise on suitable litterature for a beginner in bicategory-theory. The litterature I have found so far is:

Kelly, Street Review of the elements of 2-categories Borceux Handbook of categorical algebra 1

I have also ordered the following article:

Benabou Introduction to bicategories

So far I have only read Borceux's book but it contains mainly definitions. In particular I have difficulties understanding the need for (and consequences of) the coherence axioms associated with the natural isomorphisms expressing the associativity and identity 'axioms'.

/Lars Lindqvist