Proof by Contradiction

Thm: Place any bet on the occurrence of an event E with a stake of P (in any currency) with me and I will lose it.

Proof by Contradiction :

I can disprove any counter claim of the existence of a bet on the occurrence of an event E' with a stake of P' with me in which I win, by taking a parallel bet that if we indeed find such a bet, I shall hand you P'/2 (in the same currency) otherwise you pay me 3P'/2 (in the same currency). You must understand that the odds are stacked more on your side; thats why there's a differential payment for the parallel bet.

To make the proof even more fun, one can try disproving with even higher stakes!!!