Hey lads.
A friend of mine came up with a proof that's really convoluted, does a few sequential exhaustions and needs to prove a bunch of intermediate results through contradiction, and he can't see any way to simplify it, so he's been looking into diagrammatic explanations of proofs by exhaustion, and he wanted to know if you lads knew any, so he asked me to make this thread.
Please help, he really needs it for his PhD thesis.