"Breaking every single encryption algorithm" Hardly. For a start one-time pad (say using XOR) is a perfectly valid encryption algorithm (and its actually used

"Breaking every single encryption algorithm" Hardly. For a start one-time pad (say using XOR) is a perfectly valid encryption algorithm (and its actually used in the wild) and won't be affected a iota by P = NP. Same for Carter-Wegman. Then: "If P=NP, you could still have a cipher that decrypts in linear time with the key and n^1000 time without the key. So it's breakable in polynomial time, yet cryptographically secure." Taken from Schneier: http://www.schneier.com/blog/archives/2010/08/p_np_1.html http://www.schneier.com/blog/archives/2010/08/p_np_1.html I don't disagree with the fact that it would be a major discovery but I very much dispute your overgeneralization about the implication regarding cryptography : )