Finally, even if we later find out that lo and behold, the inference algorithm we hard-coded into our AGI circuits was actually not so great, and somebody comes along with a much better one . . . that is still not an argument for simulating the algorithm in software.
If we have many generations of rapid improvement of the algorithms this will be much easier if one doesn't need to make new hardware each time.
Not at all true. The class of statistical inference algorithms including Bayesian Networks and the cortex are both extremely flexible and greatly benefit from 'hard-wiring' it.
The general trend should still occur this way. I'm also not sure that you can reach that conclusion about the cortex given that we don't have a very good understanding of how the brain's algorithms function.
he cortex doesn't have a specialized vision circuit - there appears to be just one general purpose circuit it uses for everything. The visual regions become visual regions on account of . . processing visual input data.
That seems plausibly correct but we don't actually know that. Given how much humans rely on vision it isn't at all implausible that there have been subtle genetic tweaks that make our visual regions more effective in processing visual data (I don't know the literature in this area at all).
To be more precise we should speak of computational complexity and bitops. The best known factorization algorithms are running time exponential for the number of input bits.
Incorrect, the best factoring algorithms are subexponential. See for example the quadratic field sieve and the number field sieve both of which have subexponential running time. This has been true since at least the early 1980s (there are other now obsolete algorithms that were around before then that may have had slightly subexponential running time. I don't know enough about them in detail to comment.)
But factoring small primes is still easy in the absolute cost sense.
Factoring primes is always easy. For any prime p, it has no non-trivial factorizations. You seem to be confusing factorization with primality testing. The second is much easier than the first; we've had Agrawal's algorithm which is provably polynomial time for about a decade. Prior to that we had a lot of efficient tests that were empirically faster than our best factorization procedures. We can determine the primality of numbers much larger than those we can factor.
Factoring is also easy in the algorithmic sense, as the best algorithms are very simple and short.
Really? The general number field sieve is simple and short? Have you tried to understand it or write an implementation? Simple and short compared to what exactly?
I'm having a hard time understanding what you really mean by saying "the narrow set of tasks which humans can do decently such as vision". What about quantum mechanics, computer science, mathematics, game design, poetry, economics, sports, art, or comedy? One could probably fill a book with the narrow set of tasks that humans can do decently.
There are some tasks where we can argue that humans are doing a good job by comparison to others in the animal kingdom. Vision is a good example of this (we have some of the best vision of any mammal.) The rest are tasks which no other entities can do very well, and we don't have any good reason to think humans are anywhere near good at them in an absolute sense. Note also that most humans can't do math very well (Apparently 10% or so of my calculus students right now can't divide one fraction by another). And the vast majority of poetry is just awful. It isn't even obvious to me that the "good" poetry isn't labeled that way in part simply from social pressure.
I'm not sure what you mean by this or how it relates. If you could do face recognition that fast . . it's not impressive?
A lot of the tasks that humans have specialized in are not generally bottlenecks for useful computation. Improved facial recognition isn't going to help much with most of the interesting stuff, like recursive self-improvement, constructing new algorithms, making molecular nanotech, finding a theory of everything, figuring out how Fred and George tricked Rita, etc.
The main computational cost of every main competing AGI route I've seen involves some sort of deep statistical inference, and this amounts to a large matrix multiplication possibly with some non-linear stepping or a normalization. Neural nets, bayesian nets, whatever - if you look at the mix of required instructions, it amounts to a massive repetition of simple operations that are well suited to hardware optimization.
This seems to be a good point.
This is mostly irrelevant, but think complexity theorists use a weird definition of exponential according to which GNFS might still be considered exponential - I know when they say "at most exponential" they mean O(e^(n^k)) rather than O(e^n), so it seems plausible that by "at least exponential" they might mean Omega(e^(n^k)) where now k can be less than 1.
EDIT: Nope, I'm wrong about this. That seems kind of inconsistent.
Many folk here on LW take the simulation argument (in its more general forms) seriously. Many others take Singularitarianism1 seriously. Still others take Tegmark cosmology (and related big universe hypotheses) seriously. But then I see them proceed to self-describe as atheist (instead of omnitheist, theist, deist, having a predictive distribution over states of religious belief, et cetera), and many tend to be overtly dismissive of theism. Is this signalling cultural affiliation, an attempt to communicate a point estimate, or what?
I am especially confused that the theism/atheism debate is considered a closed question on Less Wrong. Eliezer's reformulations of the Problem of Evil in terms of Fun Theory provided a fresh look at theodicy, but I do not find those arguments conclusive. A look at Luke Muehlhauser's blog surprised me; the arguments against theism are just not nearly as convincing as I'd been brought up to believe2, nor nearly convincing enough to cause what I saw as massive overconfidence on the part of most atheists, aspiring rationalists or no.
It may be that theism is in the class of hypotheses that we have yet to develop a strong enough practice of rationality to handle, even if the hypothesis has non-negligible probability given our best understanding of the evidence. We are becoming adept at wielding Occam's razor, but it may be that we are still too foolhardy to wield Solomonoff's lightsaber Tegmark's Black Blade of Disaster without chopping off our own arm. The literature on cognitive biases gives us every reason to believe we are poorly equipped to reason about infinite cosmology, decision theory, the motives of superintelligences, or our place in the universe.
Due to these considerations, it is unclear if we should go ahead doing the equivalent of philosoraptorizing amidst these poorly asked questions so far outside the realm of science. This is not the sort of domain where one should tread if one is feeling insecure in one's sanity, and it is possible that no one should tread here. Human philosophers are probably not as good at philosophy as hypothetical Friendly AI philosophers (though we've seen in the cases of decision theory and utility functions that not everything can be left for the AI to solve). I don't want to stress your epistemology too much, since it's not like your immortal soul3 matters very much. Does it?
Added: By theism I do not mean the hypothesis that Jehovah created the universe. (Well, mostly.) I am talking about the possibility of agenty processes in general creating this universe, as opposed to impersonal math-like processes like cosmological natural selection.
Added: The answer to the question raised by the post is "Yes, theism is wrong, and we don't have good words for the thing that looks a lot like theism but has less unfortunate connotations, but we do know that calling it theism would be stupid." As to whether this universe gets most of its reality fluid from agenty creators... perhaps we will come back to that argument on a day with less distracting terminology on the table.
1 Of either the 'AI-go-FOOM' or 'someday we'll be able to do lots of brain emulations' variety.
2 I was never a theist, and only recently began to question some old assumptions about the likelihood of various Creators. This perhaps either lends credibility to my interest, or lends credibility to the idea that I'm insane.
3 Or the set of things that would have been translated to Archimedes by the Chronophone as the equivalent of an immortal soul (id est, whatever concept ends up being actually significant).