The response Anna and I give in our forthcoming chapter "Intelligence Explosion: Evidence and Import" is the following:

Chalmers (2010) suggested that AI will lead to intelligence explosion if an AI is produced by an "extendible method," where an extendible method is "a method that can easily be improved, yielding more intelligent systems." McDermott (2012a, 2012b) replies that if P≠NP (see Goldreich 2010 for an explanation) then there is no extendible method. But McDermott's notion of an extendible method is not the one essential to the possibility of intelligence explosion. McDermott's formalization of an "extendible method" requires that the program generated by each step of improvement under the method be able to solve in polynomial time all problems in a particular class — the class of solvable problems of a given (polynomially step-dependent) size in an NP-complete class of problems. But this is not required for an intelligence explosion in Chalmers' sense (and in our sense). What intelligence explosion (in our sense) would require is merely that a program self-improve to vastly outperform humans, and we argue for the plausibility of this in section 3 of our chapter. Thus while we agree with McDermott that it is probably true that P≠NP, we do not agree that this weighs against the plausibility of intelligence explosion. (Note that due to a miscommunication between McDermott and the editors, a faulty draft of McDermott (2012a) was published in Journal of Consciousness Studies. We recommend reading the corrected version at http://cs-www.cs.yale.edu/homes/dvm/papers/chalmers-singularity-response.pdf.)

I sent this to Drew and he said he agreed with our rebuttal.