On Thu, 14 Oct 2004, Vaughan Pratt wrote:
Since I've always associated modules (and hence bimodules) with rings (and semimodules with semirings), at the very least I'd expect this notion to be called something like "abstract bimodule" to indicate independence of any additive or even semiadditive structure.
I think that category-theorists long ago sold the pass on the idea that the term "module" implies the presence of additive structure; so I am happy to accept "bimodule" in this context. The trouble with "bipartite" is that bipartite graph people are generally non-directed, so that there is a complete symmetry between the two parts -- which doesn't exist in Vaughan's case. Peter Johnstone 18-Oct-2004 09:42:44 -0300,2424;000000000000-00000000