Happy 175th birthday Moritz Pasch! The German mathematician was born on November 8, 1843. Pasch specialized in the foundations of geometry. He is best remembered for Pasch's axiom, which he discovered in 1882. Although axioms do not require proofs, in this week's problem we celebrate Pasch's birthday by- you guessed it- proving Pasch's axiom. Why? Because proofs are FUN . Solution: Video: