This is a somewhat oblique answer. My recollection is that I read an obituary for Brauer. I don't remember the details except it may have been written by Alperin. Anyway the obituary said Brauer was simultaneously a specialist and a generalist. He was a specialist in the sense that he was only interested in the modular representation theory of finite groups. He was a generalist in that he was prepared to learn any area of mathematics that was relevant to this area and consequently he had learnt a broad range of mathematics.