Prior to encountering category theory, Bourbaki had a notion of isomorphism but no general notion of morphism. See this letter from. Andre Weil to Claude Chevalley, Oct. 15, 1951: \begin{quotation} As you know, my honorable colleague Mac~Lane maintains every notion of structure necessarily brings with it a notion of homomorphism, which consists of indicating, for each of the data that make up the structure, which ones behave covariantly and which contravariantly [\dots] what do you think we can gain from this kind of consideration? (quoted in Corry ~\cite[p. 380] Modern Algebra and the Rise of Mathematical Structures}, Basel: Birkh{\"a}user 1996.\end{quotation} On Mon, May 21, 2012 at 6:49 PM, Staffan Angere <Staffan.Angere@fil.lu.se> wrote:
Dear categorists,
and also, hello everyone, since this is my first post here! I'm wondering about the connection of Bourbaki to category theory. The copy of "Theory of Sets" that I have says it's written in 1970. Yet, Dieudonné famously saiid that the theory of functors subsumed Bourbaki's theory of structures... and, also, Bourbaki's theory of structures is very clearly a theory of a type of concrete categories. On the other hand, I've seen claims that the categorists' use of "morphism" comes from Bourbaki. So who was first? Does anyone here know when Bourbaki's theory of structures was really conceived? I guess this might be self-evident to anyone born during the 1st half of the 20th century, but it has turned out to be really hard to find out for me.
Thanks in advance, staffan
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