Want to take part in these discussions? Sign in if you have an account, or apply for one below
Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.
Added a “warning” for something that tripped me up: the classifying topos of a classical first-order theory is typically not Boolean, even though the classifying pretopos is Boolean. For a topos to be Boolean is much stronger – as Blass and Scedrov showed, it implies $\aleph_0$-categoricity.
This article states that
Every cartesian closed Boolean pretopos is in fact a topos.
Is every cartesian closed Boolean category a topos as well?
1 to 2 of 2