Proof of God!
God exists since mathematics is consistent, and the devil exists since its consistency cannot be proved. - Hermann Weyl
PS. for those who doesn’t know what is consistency of mathematics: It means if ‘currently’ 2 times 2 is 4, in future if we try it again, result will remain 4! It might seem obvious, but Kurt Gödel showed the consistency of the mathematics cannot be proved, so we believe mathematics is consistent but we can not prove it! You can imagine what kind of nightmare it was for mathematicians when Gödel announced his theory. Click here for more information.