Here's a proof of Cantor's Theorem in Metamath, which is one of the simplest formal systems in the world: http://us.metamath.org/mpegif/ruc.html http://us.metam

Here's a proof of Cantor's Theorem in Metamath, which is one of the simplest formal systems in the world: http://us.metamath.org/mpegif/ruc.html http://us.metamath.org/mpegif/ruc.html