zoran skoda wrote:
The remark that as a proponent of "structures" Bourbaki had to include categories is anyway a bit lacking an argument.
I think that as a 'proponent of "structures"' Bourbaki had NOT include categories - and not only because of the size problem. A more fundamental reason seems me to be this. Structures are things determined up to isomorphism; in the structuralist mathematics the notion of isomorphism is basic and the notion of general morphism is derived (as in Bourbaki). In CT this is the other way round: the notion of general morphism is basic while isos are defined through a specific property (of reversibility). This is why the inclusion of CT would require a revision of fundamentals of Bourbaki's structuralist thinking. Although CT for obvious historical reasons is closely related to structuralist mathematics it is not, in my understanding, a part of structuralist mathematics - at least not if one takes CT *seriously*, i.e. as foundations. best, andrei