Abstract

The situation in constructive mathematics in the nineties is so vastly different from that in the thirties, that it is worthwhile to pause a moment to survey the development in the intermediate years. In doing so, I follow the example of Heyting, who at certain intervals took stock of intuitionistic mathematics, which for a long time was the only variety of constructive mathematics. Heyting entered the foundational debate in 1930 at the occasion of the famous Königsberg meeting