He thought the concept of geometry without Euclid was silly.
"No it's not. You assume Euclid's axioms. Just stop assuming them and they go away," I said.
An unabashed Cartesian, he didn't know why what seemed clear and distinct to him today could be just a replacable presupposition.
They're not obvious, they're paradigms. You put them in place and they explain the world. You may like this explaination better but it's not blinking clear and distinct.
Sometimes I have a headache and I wish simple Cartesians would stay in the closet.