New Comment
3 comments, sorted by Click to highlight new comments since: Today at 4:43 AM

I find the comparison of rationality to logical positivism as a philosophical movement compelling, especially in the sense that rationality may not get the credit for much in the long run but may well prove to be important for setting the course of thinking for many folks even if it's to give them antitheses to reason against.

Though to be fair most philosophy seems convergent to me and remaining disagreements often seem ones of interpretation, outliers like theologians not withstanding.

I like this, bout halfway down in the AMA

"Some would argue that in order for the universe to be simulated, it would have to be computed or, basically, be mathematical. Is there a way to prove this by searching for concrete evidence of computation in nature? If so, how>


i'd say that to be simulated it would have to be computed, almost by definition. if it's a perfect simulation, it may be impossible to get concrete evidence, since the evidence one gets in a perfect simulation will be the same as in the non-simulated universe that it's a simulation of. if it's an imperfect simuilation there may be all sorts of potential evidence: everything from red pills or finding the source code to subtle evidence of imperfect approximations. zohreh davoudi and colleagues at MIT have a nice paper on certain ways in which approximations can show up empirically, which they use to suggest at least a potential source of evidence that we are living in an approximating simulation. there also are various ways that we could get evidence that the physics of our world is digital, which is an idea that is at least connected to the idea of a simulation (though physics could be digital without being simulated, and could be simulated without being digital).

and the theory that our observations , set the physical constraints of the sim.

r/philosophyAMA I'm David Chalmers, philosopher interested in consciousness, technology, and many other things. AMA. u/davidchalmers5h I'm a philosopher at New York University and the Australian National University. I'm interested in consciousness: e.g. the hard problem (see also this TED talk, the science of consciousness, zombies, and panpsychism. Lately I've been thinking a lot about the philosophy of technology: e.g. the extended mind (another TED talk), the singularity, and especially the universe as a simulation and virtual reality. I have a sideline in metaphilosophy: e.g. philosophical progress, verbal disputes, and philosophers' beliefs. I help run PhilPapers and other online resources. Here's my website (it was cutting edge in 1995; new version coming soon).

Recent Links:

"What It's Like to be a Philosopher" - (my life story)

Consciousness and the Universe - (a wide-ranging interview)

Reverse Debate on Consciousness - (channeling the other side)

The Mind Bleeds into the World: A Conversation with David Chalmers - (issues about VR, AI, and philosophy that I've been thinking about recently)

OUP Books

Oxford University has made some books available at a 30% discount by using promocode AAFLYG6** on the site. Those titles are:

The Conscious Mind: In Search of a Fundamental Theory

Panpsychism: Contemporary Perspectives

The Character of Consciousness

Constructing the World


Hi everyone! I got a headstart answering questions on the announcement thread and have posted answers to those. Answering other questions as they come in now!

328 Comments843 Best

/u/willbell asked:

Holy crap it's you. What do you see in Less Wrong? They seem very intent on replacing areas of philosophy with non-critical versions of those areas (e.g. aesthetics -> neuroaesthetics, as if those are asking the same questions, etc) so I find them hard to take seriously, yet you seem to.

I never really got the p-zombie argument, you use it as an argument for non-physicalism but how is it that you move from 'p-zombies are conceivable' to 'mind and brain are actually distinct in a non-physicalist way'? Why couldn't the further fact in which we differ from a world of p-zombies be certain facts about how metaphysical emergence works rather than some sort of psychological stuff? What is the best argument against non-reductive physicalism in your opinion? At any point when you had longer hair, did you ever consider quitting philosophy and starting a rock and roll band?

i don't know about the less wrong blog specifically (it seems to be moribund these days), but i've seen a lot of interesting ideas come from the "rationalist" community of which it has been a focal point. the most obvious is the issue of AI safety in the context of superintelligence, which has become a huge issue both inside and outside academia, and for which the main credit has to go jointly to nick bostrom (who's an academic philosopher but also connected to that community) and eliezer yudkowsky (who's a nonacademic philosopher who founded the less wrong blog and has been at the center of that community), who explored the issues for years before the world was paying much attention. there was also a very interesting proto-decision-theory (timeless or updateless decision theory) developed a few years by eliezer and others at less wrong, though i've been disappointed that no one has been able to give a well-developed clear and rigorous statement of the theory since then. i also like very much the idea of "applied rationality" that was a focus on less wrong and for the center for applied rationality, which grew out of this community. it's surprising that although there's a huge amount of applied ethics in philosophy, there's not very much applied epistemology, and i give the rationalist community credit for developing that approach. finally, the whole effective altruism movement is at least loosely connected to this community (though it was started in large part by academic philosophers), and i think a lot that's of both philosophical and practical value has come out of that.

of course as with most communities, this one has its own idiosyncracies and pathologies. many ideas put forward are oversimplistic or reinvent wheels, and it hasn't helped that ideas have often been circulated in half-baked forms on blogs or in the oral tradition. and of course some rationalists make wildly ambitious claims about solving or dissolving traditional philosophical problems. but the same is true for the logical positivists in the 1920s and 1930s, who the rationalist community resemble in a number of respects (except that rationalists' positivism focuses on reducing problems to questions about algorithms rather than to questions about experience). the logical positivists were oversimplistic in many respects and made many mistakes, and they turned out not to solve or dissolve the deepest traditional problems, but they nevertheless did some very important philosophy. as i mention in another reply, i think having subcommunities of this sort that make their own distinctive assumptions is an important mechanism of philosophical priogress. to use your example, even if neuroaesthetics can't solve all the traditional problems of aesthetics (as i'm sure it can't), maybe the attempt will lead to interesting related ideas that help solve related problems. so i'm all in favor of having subcultures like this that generate interesting ideas so we can see where they go. maybe they'll have some bad ideas along the way, but those are easy to weed out. it's a small price to pay for generating new good ideas.

on your other questions: (2) see my paper "consciousness and its place in nature". if by "metaphysical emergence" you mean what i call "strong emergence" (in the paper "strong and weak emergence"), then i do think that's just what the further fact involves -- a sort of fundamental psychophysical law determining how consciousness emerges from the physical. (3) people use words like "reductive" in different ways, but in my view the best arguments against physicalism are equally arguments against reductive and nonreductive physicalism. (4) unfortunately i have no musical talent, as a search for "zombie blues" on youtube will conclusively demonstrate to you.