15 Sep
2017
15 Sep
'17
6:23 p.m.
On 14/09/2017 17:58, Peter Selinger wrote:
Robert Pare wrote:
He said there may come a time when we have to consider covariant functors as contravariant ones on the opposite category.
Indeed: Segal's (1974) Gamma-spaces are contravariant functors on the opposite of the category of finite pointed sets. Joachim.