New posts in Proof Theory

Writing "Semi-Formal" Proofs

How fast can the base-bumping function in Goodstein's theorem grow?

Most general formulation of Gödel's incompleteness theorems

Feit-Thompson theorem: the Odd order paper

Characterizing visual proofs

Bourbaki's epsilon-calculus notation

Reductio ad absurdum or the contrapositive?

Are there any good nonconstructive "existential metatheorems"?

What does it mean to 'discharge assumptions or premises'?