[andrewflnr]

> I think I just experienced how much self-deception there is about the world.

This is not actually a proof. It is, however, exactly the kind of soft reasoning that motivates reasonable axioms. I'm not saying it's a bad axiom, I'm saying you should know what you're doing. That way when you run into a domain where it doesn't apply very well, you know where and how to back up and restart.