Proof By Intimidation

The expanding brain meme perfectly captures the mathematician's descent into madness. Starting with "direct proof" (basic skull), we progress through increasingly galaxy-brain methods until we reach the final boss: "proof by lack of counterexample" – which is basically saying "I can't think of why I'm wrong, so I must be right." Every math professor has witnessed the horror of a student writing "clearly" or "obviously" before the most convoluted statement imaginable. And don't get me started on "proof is left as an exercise to the reader" – the academic equivalent of "figure it out yourself, I'm going to lunch." It's what professors do when they either can't solve it themselves or are too lazy to write out all the steps. Pure mathematical terrorism.