Zoltan A. Kocsis

Two applications of the point-free coderivative

We present two new applications of Simmons'point-free Cantor-Bendixson coderivative operator in intuitionistic logic. First, we use it to give a simplified proof of the recent result of Xu and Ye that the free Heyting algebra on two generators does not occur as the Heyting algebra of subterminal objects in any elementa...