New posts in Topos Theory

Subobject Classifier of a Topos is Injective

Let $\epsilon$ be a topos and let $f:Y\to X$ be a morphism. Let $M,N$ be two subobjects of $X$. Is it true that $f^*(M\cap N)=f^*(M)\cap f^*(N)$?

In a topos with a NNO, how does one define the subobject "$<$'' of $\mathbf N\times\mathbf N$?

Monomorphism into separated presheaf

What is the generally accepted pronunciation of “topoi”?

"Proper" definition of a proper map?

References to supplement Goldblatt's "Topoi"

Topos theory and higher-order logic

Elementary topoi have initial objects, why?

subobject classifier for partial orders