Shtetl-Optimized

Update (5/7): Enough!  Thanks, everyone, for asking so many imaginative questions, and please accept my apologies if yours remains unaddressed.  (It’s nothing personal: they simply came fast and furious, way faster than I could handle in an online fashion—so I gave up on chronological order and simply wrote answers in whatever order they popped into my head.)  At this point, I’m no longer accepting any new questions.  I’ll try to answer all the remaining questions by tomorrow night.

By popular request, for the next 36 hours—so, from now until ~11PM on Tuesday—I’ll have a long-overdue edition of “Ask Me Anything.”  (For the previous editions, see here, here, here, and here.)  Today’s edition is partly to celebrate my new, tenured “freedom to do whatever the hell I want” (as well as the publication after 7 years of Quantum Computing Since Democritus), but is mostly just to have an excuse to get out of changing diapers (“I’d love to, honey, but the world is demanding answers!”).  Here are the ground rules:

1. One question per person, total.
2. Please check to see whether your question was already asked in one of the previous editions—if it was, then I’ll probably just refer you there.
3. No questions with complicated backstories, or that require me to watch a video, read a paper, etc. and comment on it.
4. No questions about D-Wave.  (As it happens, Matthias Troyer will be giving a talk at MIT this Wednesday about his group’s experiments on the D-Wave machine, and I’m planning a blog post about it—so just hold your horses for a few more days!)
5. If your question is offensive, patronizing, nosy, or annoying, I reserve the right to give a flippant non-answer or even delete the question.
6. Keep in mind that, in past editions, the best questions have almost always been the most goofball ones (“What’s up with those painting elephants?”).

That’s it: ask away!

Update (5/12): I’ve finally answered all ~90 questions, a mere 4 days after the official end of the “Ask Me Anything” session!  Thanks so much to everyone for all the great questions.  For your reading convenience, here’s a guide to my answers (personal favorites are in bold):

• The probability that we live in the Matrix (see followups here, here, here, here)
• Glauber dynamics
• My behavior as Waterloo lunch organizer
• The saddest thing
• Quantum cellular automata
• P!=NP vs. P!=PSPACE
• My knowledge of general relativity
• Advantages of Dirac ket notation
• The evolution of my career goals
• Open problems related to BosonSampling
• Book-signing for Quantum Computing Since Democritus
• In an infinite universe, must all possible earthlike planets exist?
• Was 9/11 an inside job?
• The fine-structure constant and quantum computing
• Accessible open problems in complexity theory
• Tightening Razborov’s monotone lower bound for CLIQUE
• In what sense is the quadratic Grover speedup “provable”?
• Fisher information
• “Associate Professor Without Tenure”
• Is the whole universe “just” a vector in Hilbert space?
• How to initialize a qubit
• My knowledge of my tenure case
• How I’d build a quantum computer in 20-30 years
• Could God solve the halting problem?
• “Who’s yer daddy?”
• How long I’d want to live
• Could the difficulty of building a QC grow exponentially with number of qubits?
• Why does quantum computing require physically different hardware?
• The double-slit experiment and “lazy evaluation”
• Bioengineered flying horses vs. flying robot horses: which will be first?
• The last program I wrote
• How much I sleep
• Recent TCS advances with practical applications in the near future
• What I’d ask Terry Tao
• How many digits will the largest known prime have in 10 or 100 years?
• Whether I believe in free will
• The nature of time
• My progress in learning Hebrew
• Social science breakthroughs that could bring about world peace
• Superquadratic advantage of the quantum adiabatic algorithm over classical search?
• Is a classical world also a quantum world?
• The name of the blog
• John Sidles’ prognostiquestion
• Books and films for Lily to grow up with
• Does QM generate “true” randomness?
• Fictitious proofs of P!=NP
• The secret of happiness
• What I did in college
• The blowup in reducing theorem-proving to 3SAT
• Whether CUP objected to the free QCSD lecture notes
• The top 5 not-yet-written books that I’d most like to read
• Does the continuum “exist” in physical reality? (see followup here)
• Could Nature itself be inconsistent?
• Zen koan about a mouse eating cat food
• “Maybe, it’s the equality sign?”
• Classical computer is to QC as QC is to what?
• Why are CS theorists obsessed with polynomial time?
• My favorite complexity theorist
• A bad approach to factoring large integers
• Am I a Bayesian?
• How to build an intelligent machine
• Will automated theorem provers become as standard as Mathematica/Maple?
• My initiation into theoretical computer science
• How to get an 8-year-old excited about programming
• “Am I insane?”
• Levin universal search
• Brain emulation by 2023?  A $10,000 bet
• How being in “communist Berkeley” in my formative years shaped my worldview (see followup here)
• Israel vs. Apartheid South Africa
• Will useful QC precede its public announcement, or vice versa?
• My work habits
• US immigration policy
• My favorite Israeli foods
• If I guess randomly, how likely am I to get this question right?
• Busy Beaver numbers: is BB(n+1) provably much larger than BB(n)? (see followups here and here)
• Computational complexity and biological/social evolution
• P vs. NP vs. Shannon capacity of cycles problem
• Video games based on my research interests
• Bayesian reasoning when there are copies of yourself
• Pr[ PH=PSPACE | PH collapses ]
• My favorite interpretation of QM
• What I’d do if I proved P=NP
• QM and consciousness
• QM and free will
• Cultures of Clarkson, Cornell, Berkeley, IAS, Waterloo, MIT
• How I decide what’s ethical
• American vs. Chilean universities

Last month, I blogged about Sen. Tom Coburn (R-Oklahoma) passing an amendment blocking the National Science Foundation from funding most political science research.  I wrote:

This sort of political interference with the peer-review process, of course, sets a chilling precedent for all academic research, regardless of discipline.  (What’s next, an amendment banning computer science research, unless it has applications to scheduling baseball games or slicing apple pies?)

In the comments section of that post, I was pilloried by critics, who ridiculed my delusional fears about an anti-science witch hunt.  Obviously, they said, Congressional Republicans only wanted to slash dubious social science research: not computer science or the other hard sciences that people reading this blog really care about, and that everyone agrees are worthy.  Well, today I write to inform you that I was right, and my critics were wrong.  For the benefit of readers who might have missed it the first time, let me repeat that:

I was right, and my critics were wrong.

In this case, like in countless others, my “paranoid fears” about what could happen turned out to be preternaturally well-attuned to what would happen.

According to an article in Science, Lamar Smith (R-Texas), the new chair of the ironically-named House Science Committee, held two hearings in which he “floated the idea of having every NSF grant application [in every field] include a statement of how the research, if funded, ‘would directly benefit the American people.’ “  Connoisseurs of NSF proposals will know that every proposal already includes a “Broader Impacts” section, and that that section often borders on comic farce.  (“We expect further progress on the μ-approximate shortest vector problem to enthrall middle-school students and other members of the local community, especially if they happen to belong to underrepresented groups.”)  Now progress on the μ-approximate shortest vector problem also has to directly—directly—”benefit the American people.”  It’s not enough for such research to benefit science—arguably the least bad, least wasteful enterprise our sorry species has ever managed—and for science, in turn, to be a principal engine of the country’s economic and military strength, something that generally can’t be privatized because of a tragedy-of-the-commons problem, and something that economists say has repaid public investments many, many times over.  No, the benefit now needs to be “direct.”

The truth is, I find myself strangely indifferent to whether Smith gets his way or not.  On the negative side, sure, a pessimist might worry that this could spell the beginning of the end for American science.  But on the positive side, I would have been proven so massively right that, even as I held up my “Will Prove Quantum Complexity Theorems For Food” sign on a street corner or whatever, I’d have something to crow about until the end of my life.

Furthermore, the last of those things actually happened.  What won’t I do to promote Quantum Computing Since Democritus?  Enjoy!

Update: I submitted the following response to the comments over on Lubos’s blog.  Since it has some bits of general interest, I thought I’d crosspost it here while it awaits Lubos’s moderation.

Since Lubos “officially invited” me to respond to the comments here, let me now do so.

1. On “loopholes” in quantum mechanics: I completely agree with Lubos’s observation that the actual contents of my book are “conservative” about the truth of QM. Indeed, I predict that, when Lubos reads his free copy, he’ll agree with (or at least, have no objections to) the vast majority of what’s in the book. On the other hand, because I was guest-blogging about “the story of me and Lubos,” I found it interesting to highlight one area of disagreement regarding QM, rather than the larger areas of agreement.

2. On Gene Day’s patronizing accusation that I don’t “get the basics of QM or even comprehend the role of mathematics in physics”: his misreading of what I wrote is so off-base that I don’t know whether a response is even necessary.  Briefly, though: of course two formulations of QM are mathematically equivalent if they’re mathematically equivalent!  I wasn’t asking why we don’t use different mathematical structures (quaternions, the 3-norm, etc.) to describe the same physical world.  I was asking why the physical world itself shouldn’t have been different, in such a way that those other mathematical structures would have described it.  In other words: if you were God, and you tried to invent a theory that was like QM but based on those other structures, would the result necessarily be less “nice” than QM?  Would you have to give up various desirable properties of QM?  Yes?  Can you prove it?  The ball’s in your court, Mr. Day — or else you can just read my book!

3. On Lord Nelson’s accusation that I’m a “poseur”: on reflection, someone who only knew me from blog stunts like this one could easily be forgiven for getting that impression! So it might be worth pointing out for the record that I also have a “day job” outside the blogosphere, whose results you can see here if you care.

4. On my political views: I wish to clarify for Tom Vonk that I despise not only “Communists,” but the ideology of Communism itself. One of the formative experiences of my life occurred when I was an 8-year-old at Wingate Kirkland summer camp, and all the campers had to relinquish whatever candy they’d brought into a communal “bunk trunk.” The theory was that all the campers, rich and poor alike, would then share the candy equally during occasional “bunk parties.” What actually happened was that the counselors stole the candy. So, during a meeting of the entire camp, I got up and gave a speech denouncing the bunk trunk as Communism. The next day, the camp director (who had apparently been a fellow-traveler in the 1950s) sat with me at lunchtime, and told me about a very evil man named Joe McCarthy who I was in danger of becoming like. But the truth was that I’d never even heard of McCarthy at that point — I just wanted to eat candy.  And I’d give exactly the same speech today.

Like (I suppose) several billion of the world’s people, I believe in a dynamic market-based capitalist society, and also in strong environmental and other regulations to safeguard that society’s continued existence. And I don’t merely believe in that as a cynical compromise, since I can’t get the “dictatorship of the proletariat” that I want in my heart of hearts. Were I emperor of the world, progressive capitalism is precisely what I would institute. In return, perhaps, for paying a “candy tax” to keep the bunk functioning smoothly, campers could keep their remaining candy and eat or trade it to their heart’s delight.

5. On climate change: I’m not a professional climatologist, but neither is Lubos, and nor (correct me if I’m wrong) is anyone else commenting here. Accordingly, I refuse to get drawn into a debate about ice cores and tree rings and hockey sticks, since my experience is that such debates tend to be profoundly unilluminating when not conducted by experts. My position is an incredibly simple one: just like with the link between smoking and cancer, or the lack of a link between vaccines and autism, or any other issue where I lack the expertise to evaluate the evidence myself, I’ll go with what certainly looks like an overwhelming consensus among the scientists who’ve studied the matter carefully. Period. If the climate skeptics want to win me over, then the way for them to do so is straightforward: they should ignore me, and try instead to win over the academic climatology community, majorities of chemists and physicists, Nobel laureates, the IPCC, National Academies of Science, etc. with superior research and arguments.

To this, the skeptics might respond: but of course we can’t win over the mainstream scientific community, since they’re all in the grip of an evil left-wing conspiracy or delusion!  Now, that response is precisely where “the buck stops” for me, and further discussion becomes useless.  If I’m asked which of the following two groups is more likely to be in the grip of a delusion — (a) Senate Republicans, Freeman Dyson, and a certain excitable string-theory blogger, or (b) virtually every single expert in the relevant fields, and virtually every other chemist and physicist who I’ve ever respected or heard of — well then, it comes down to a judgment call, but I’m 100% comfortable with my judgment.

Update (1/18): Some more information has emerged.  First, it’s looking like the prosecution’s strategy was to threaten Aaron with decades of prison time, in order to force him to accept a plea bargain involving at most 6 months.  (Carmen Ortiz issued a statement that conveniently skips the first part of the strategy and focuses on the second.)  This is standard operating procedure in our wonderful American justice system, due (in part) to the lack of resources actually to bring most cases to trial.  The only thing unusual about the practice is the spotlight being shone on it, now that it was done not to some poor unknown schmuck but to a tortured prodigy and nerd hero.  Fixing the problem would require far-reaching changes to our justice system.

Second, while I still strongly feel that we should await the results of Hal Abelson’s investigation, I’ve now heard from several sources that there was some sort of high-level decision at MIT—by whom, I have no idea—not to come out in support of Aaron.  Crucially, though, I’m unaware of the faculty (or students, for that matter) ever being consulted about this decision, or even knowing that there was anything for MIT to decide.  Yesterday, feeling guilty about having done nothing to save Aaron, I found myself wishing that either he or his friends or parents had made an “end run” around the official channels, and informed MIT faculty and students directly of the situation and of MIT’s ability to help.  (Or maybe they did, and I simply wasn’t involved?)

Just to make sure I hadn’t missed anything, I searched my inbox for “Swartz”, but all I found relevant to the case were a couple emails from a high-school student shortly after the arrest (for a project he was doing about the case), and then the flurry of emails after Aaron had already committed suicide.  By far the most interesting thing that I found was the following:

Aaron Swartz (December 12, 2007): I’m really enjoying the Democritus lecture notes. Any chance we’ll ever see lecture 12?

My response: It’s a-comin’!

As I wrote on this blog at the time of Aaron’s arrest: I would never have advised him to do what he did.  Civil disobedience can be an effective tactic, but off-campus access to research papers simply isn’t worth throwing your life away for—especially if your life holds as much spectacular promise as Aaron’s did, judging from everything I’ve read about him.  At the same time, I feel certain that the world will eventually catch up to Aaron’s passionate belief that the results of publicly-funded research should be freely available to the public.  We can honor Aaron’s memory by supporting the open science movement, and helping the world catch up with him sooner.

Sorry for the terrible pun.  Today’s post started out as a comment on a review of the movie Lincoln on Sean Carroll’s blog, but it quickly become too long, so I made it into a post on my own blog.  Apparently I lack Abe’s gift for concision.

I just saw Lincoln — largely inspired by Sean’s review — and loved it.  It struck me as the movie that Lincoln might have wanted to be made about himself: it doesn’t show any of his evolution, but at least it shows the final result of that evolution, and conveys the stories, parables, and insight into human nature that he had accumulated by the end of his life in a highly efficient manner.

Interestingly, the Wikipedia page says that Spielberg commissioned, but then ultimately rejected, two earlier scripts that would have covered the whole Civil War period, and (one can assume) Lincoln’s process of evolution.  I think that also could have been a great movie, but I can sort-of understand why Spielberg and Tony Kushner made the unusual choice they did: at the level of detail they wanted, it seems like it would be impossible to do justice to Lincoln’s whole life, or even the last five years of it, in anything less than a miniseries.

I agree with the many people who pointed out that the movie could have given more credit to those who were committed antislavery crusaders from the beginning—rather than those like Lincoln, who eventually came around to the positions we now associate with him after a lot of toying with ideas like blacks self-deporting to Liberia.  But in a way, the movie didn’t need to dole out such credit: today, we know (for example) that Thaddeus Stevens had history and justice 3000% on his side, so the movie is free to show him as the nutty radical that he seemed to most others at the time.  And there’s even a larger point: never the most diligent student of history, I (to take one embarrassing example) had only the vaguest idea who Thaddeus Stevens even was before seeing the movie.  Now I’ve spent hours reading about him, as well as about Charles Sumner, and being moved by their stories.

(At least I knew about the great Frederick Douglass, having studied his Narrative in freshman English class.  Douglass and I have something in common: just as a single sentence he wrote, “I would unite with anybody to do right and with nobody to do wrong,” will reverberate through the ages, so too, I predict, will a single sentence I wrote: “Australian actresses are plagiarizing my quantum mechanics lecture to sell printers.”)

More broadly, I think it’s easy for history buffs to overestimate how much people already know about this stuff.  Indeed, I can easily imagine that millions of Americans who know Lincoln mostly as “the dude on the $5 bill (who freed some slaves, wore a top hat, used the word ‘fourscore,’ and got shot)” will walk out of the cineplex with a new and ~85% accurate appreciation for what Lincoln did to merit all that fuss, and why his choices weren’t obvious to everyone else at the time.

Truthfully, though, nothing made me appreciate the movie more than coming home and reading countless comments on movie review sites denouncing Abraham Lincoln as a bloodthirsty war criminal, and the movie as yet more propaganda by the victors rewriting history.  Even on Sean’s blog we find this, by a commenter named Tony:

I’m not one who believes we have to go to war to solve every problem we come across, I can’t believe that Lincoln couldn’t have found a solution to states rights and slavery in a more peaceful course of action. It seems from the American Revolutionary war to the present it has been one war after another … The loss of life of all wars is simply staggering, what a waste of humanity.

Well look, successive presidential administrations did spend decades trying to find a peaceful solution to the “states rights and slavery” issue; the massive failure of their efforts might make one suspect that a peaceful solution didn’t exist.  Indeed, even if Lincoln had simply let the South secede, my reading of history is that issues like the return of fugitive slaves, or competition over Western territories, would have eventually led to a war anyway.  I’m skeptical that, in the limit t→∞, free and slave civilizations could coexist on the same continent, no matter how you juggled their political organization.

I’ll go further: it even seems possible to me that the Civil War ended too early, with the South not decimated enough.  After World War II, Japan and Germany were successfully dissuaded even from “lite” versions of their previous plans, and rebuilt themselves on very different principles.  By contrast, as we all know, the American South basically refused for the next century to admit it had lost: it didn’t try to secede again, but it did use every means available to it to reinstate de facto slavery or something as close to that as possible.  All the civil-rights ideals of the 1960s had already been clearly articulated in the 1860s, but it took another hundred years for them to get implemented.  Even today, with a black President, the intellectual heirs of the Confederacy remain a force to be reckoned with in the US, trying (for example) to depress minority voter turnout through ID laws, gerrymandering, and anything else they think they can possibly get away with.  The irony, of course, is that the neo-Confederates now constitute a nontrivial fraction of what they proudly call “the party of Lincoln.”  (Look at the map of blue vs. red states, and compare it to the Mason-Dixon line.  Even the purple states correspond reasonably well to the vacillating border states of 1861.)

So that’s why it seems important to have a movie every once in a while that shows the moral courage of people like Lincoln and Thaddeus Stevens, and that names and shames the enthusiastic defenders of slavery—because while the abolitionists won the battle, on some fronts we’re still fighting the war.

Update (Nov. 8): Slate’s pundit scoreboard.

Update (Nov. 6): In crucial election news, a Florida woman wearing an MIT T-shirt was barred from voting, because the election supervisor thought her shirt was advertising Mitt Romney.

At the time of writing, Nate Silver is giving Obama an 86.3% chance.  I accept his estimate, while vividly remembering various admittedly-cruder forecasts the night of November 5, 2000, which gave Gore an 80% chance.  (Of course, those forecasts need not have been “wrong”; an event with 20% probability really does happen 20% of the time.)  For me, the main uncertainties concern turnout and the effects of various voter-suppression tactics.

In the meantime, I wanted to call the attention of any American citizens reading this blog to the wonderful Election FAQ of Peter Norvig, director of research at Google and a person well-known for being right about pretty much everything.  The following passage in particular is worth quoting.

Is it rational to vote?

Yes. Voting for president is one of the most cost-effective actions any patriotic American can take.

Let me explain what the question means. For your vote to have an effect on the outcome of the election, you would have to live in a decisive state, meaning a state that would give one candidate or the other the required 270th electoral vote. More importantly, your vote would have to break an exact tie in your state (or, more likely, shift the way that the lawyers and judges will sort out how to count and recount the votes). With 100 million voters nationwide, what are the chances of that? If the chance is so small, why bother voting at all?

Historically, most voters either didn’t worry about this problem, or figured they would vote despite the fact that they weren’t likely to change the outcome, or vote because they want to register the degree of support for their candidate (even a vote that is not decisive is a vote that helps establish whether or not the winner has a “mandate”). But then the 2000 Florida election changed all that, with its slim 537 vote (0.009%) margin.

What is the probability that there will be a decisive state with a very close vote total, where a single vote could make a difference? Statistician Andrew Gelman of Columbia University says about one in 10 million.

That’s a small chance, but what is the value of getting to break the tie? We can estimate the total monetary value by noting that President George W. Bush presided over a $3 trillion war and at least a $1 trillion economic melt-down. Senator Sheldon Whitehouse (D-RI) estimated the cost of the Bush presidency at $7.7 trillion. Let’s compromise and call it $6 trillion, and assume that the other candidate would have been revenue neutral, so the net difference of the presidential choice is $6 trillion.

The value of not voting is that you save, say, an hour of your time. If you’re an average American wage-earner, that’s about $20. In contrast, the value of voting is the probability that your vote will decide the election (1 in 10 million if you live in a swing state) times the cost difference (potentially $6 trillion). That means the expected value of your vote (in that election) was $600,000. What else have you ever done in your life with an expected value of $600,000 per hour? Not even Warren Buffett makes that much. (One caveat: you need to be certain that your contribution is positive, not negative. If you vote for a candidate who makes things worse, then you have a negative expected value. So do your homework before voting. If you haven’t already done that, then you’ll need to add maybe 100 hours to the cost of voting, and the expected value goes down to $6,000 per hour.)

I’d like to embellish Norvig’s analysis with one further thought experiment.  While I favor a higher figure, for argument’s sake let’s accept Norvig’s estimate that the cost George W. Bush inflicted on the country was something like $6 trillion.  Now, imagine that a delegation of concerned citizens from 2012 were able to go back in time to November 5, 2000, round up 538 lazy Gore supporters in Florida who otherwise would have stayed home, and bribe them to go to the polls.  Set aside the illegality of the time-travelers’ action: they’re already violating the laws of space, time, and causality, which are well-known to be considerably more reliable than Florida state election law!  Set aside all the other interventions that also would’ve swayed the 2000 election outcome, and the 20/20 nature of hindsight, and the insanity of Florida’s recount process.  Instead, let’s simply ask: how much should each of those 538 lazy Floridian Gore supporters have been paid, in order for the delegation from the future to have gotten its money’s worth?

The answer is a mind-boggling ~$10 billion per voter.  Think about that: just for peeling their backsides off the couch, heading to the local library or school gymnasium, and punching a few chads (all the way through, hopefully), each of those 538 voters would have instantly received the sort of wealth normally associated with Saudi princes or founders of Google or Facebook.  And the country and the world would have benefited from that bargain.

No, this isn’t really a decisive argument for anything (I’ll leave it to the commenters to point out the many possible objections).  All it is, is an image worth keeping in mind the next time someone knowingly explains to you why voting is a waste of time.

Update (10/31): While I continue to engage in surreal arguments in the comments section—Scott, I’m profoundly disappointed that a scientist like you, who surely knows better, would be so sloppy as to assert without any real proof that just because it has tusks and a trunk, and looks and sounds like an elephant, and is the size of the elephant, that it therefore is an elephant, completely ignoring the blah blah blah blah blah—while I do that, there are a few glimmerings that the rest of the world is finally starting to get it.  A new story from The Onion, which I regard as almost the only real newspaper left:

Nation Suddenly Realizes This Just Going To Be A Thing That Happens From Now On

Update (11/1): OK, and this morning from Nicholas Kristof, who’s long been one of the rare non-Onion practitioners of journalism: Will Climate Get Some Respect Now?

I’m writing from the abstract, hypothetical future that climate-change alarmists talk about—the one where huge tropical storms batter the northeastern US, coastal cities are flooded, hundreds of thousands are evacuated from their homes, etc.  I always imagined that, when this future finally showed up, at least I’d have the satisfaction of seeing the deniers admit they were grievously wrong, and that I and those who think similarly were right.  Which, for an academic, is a satisfaction that has to be balanced carefully against the possible destruction of the world.  I don’t think I had the imagination to foresee that the prophesied future would actually arrive, and that climate change would simultaneously disappear as a political issue—with the forces of know-nothingism bolder than ever, pressing their advantage into questions like whether or not raped women can get pregnant, as the President weakly pleads that he too favors more oil drilling.  I should have known from years of blogging that, if you hope for the consolation of seeing those who are wrong admit to being wrong, you hope for a form of happiness all but unattainable in this world.

Yet, if the transformation of the eastern seaboard into something out of the Jurassic hasn’t brought me that satisfaction, it has brought a different, completely unanticipated benefit.  Trapped in my apartment, with the campus closed and all meetings cancelled, I’ve found, for the first time in months, that I actually have some time to write papers.  (And, well, blog posts.)  Because of this, part of me wishes that the hurricane would continue all week, even a month or two (minus, of course, the power outages, evacuations, and other nasty side effects).  I could learn to like this future.

At this point in the post, I was going to transition cleverly into an almost (but not completely) unrelated question about the nature of causality.  But I now realize that the mention of hurricanes and (especially) climate change will overshadow anything I have to say about more abstract matters.  So I’ll save the causality stuff for tomorrow or Wednesday.  Hopefully the hurricane will still be here, and I’ll have time to write.

(Note for non-US readers: This will be another one of my America-centric posts.  But don’t worry, it’s probably one you’ll agree with.)

There’s one argument in favor of gun control that’s always seemed to me to trump all others.

In your opinion, should private citizens should be allowed to own thermonuclear warheads together with state-of-the-art delivery systems?  Does the Second Amendment give them the right to purchase ICBMs on the open market, maybe after a brief cooling-off period?  No?  Why not?

OK, whatever grounds you just gave, I’d give precisely the same grounds for saying that private citizens shouldn’t be allowed to own assault weapons, and that the Second Amendment shouldn’t be construed as giving them that right.  (Personally, I’d ban all guns except for the bare minimum used for sport-shooting, and even that I’d regulate pretty tightly.)

Now, it might be replied that the above argument can be turned on its head: “Should private citizens be allowed to own pocket knives?  Yes, they should?  OK then, whatever grounds you gave for that, I’d give the precisely same grounds for saying that they should be allowed to own assault weapons.”

But crucially, I claim that’s a losing argument for the gun-rights crowd.  For as soon as we’re anywhere on the slippery slope—that is, as soon as it’s conceded that the question hinges, not on absolute rights, but on an actual tradeoffs in actual empirical reality—then the facts make it blindingly obvious that letting possibly-deranged private citizens buy assault weapons is only marginally less crazy than letting them buy ICBMs.

[Related Onion story]

1. The 1936 Berlin Olympics, in which American participation was ensured by the racist, sexist, antisemitic, Nazi-sympathizing future decades-long IOC president Avery Brundage (also, the IOC’s subsequent failure to accept responsibility for its role in legimitizing Hitler).

2. The 1972 Munich Olympics (and the IOC’s subsequent refusal even to memorialize the victims, apparently for fear of antagonizing those Olympic countries that still celebrate the murder of the 11 Israeli athletes).

3. Even after you leave out 1936 and 1972, the repeated granting of unearned legitimacy to the world’s murderous dictatorships—as well as “glory” to those countries most able to coerce their children into lives of athletic near-slavery (or, in the case of more “civilized” countries, outspend their rivals).

4. The sanctimonious fiction that, after all this, we need the Olympics because of their contributions to world peace and brotherhood (a claim about which we now arguably have a century of empirical data).

5. The double-standard that holds “winning a medal is everything” to be a perfectly-reasonable life philosophy for a gymnast, yet would denounce the same attitude if expressed by a scientist or mathematician.

6. The increasingly-convoluted nature of what it is that the athletes are supposed to be optimizing (“run the fastest, but having taken at most these performance-enhancing substances and not those, unless of course you’re a woman with unusually-high testosterone, in which case you must artificially decrease your testosterone before competing in order to even things out”)

7. The IOC’s notorious corruption, and the fact that hosting the Olympics is nevertheless considered such a wonderful honor and goal for any aspiring city.

8. The IOC’s farcical attempts to control others’ use of five interlocked rings and of the word “Olympics.”

9. The fact that swimmers have to use a particular stroke, rather than whichever stroke will propel them through the water the fastest (alright, while the “freestyle” rules still seem weird to me, I’m taking this one out given the amount of flak it’s gotten)

10. The fact that someone like me, who knows all the above, and who has less interest in sports than almost anyone on earth, is still able to watch an Olympic event and care about its outcome.

See, now this is precisely why I became a CS professor: so that if anyone asked, I could give not merely my opinion, but my professional, expert opinion, on the question of whether psychopathic Terminators will kill us all.

My response (slightly edited) is below.

Dear John,

I fear that your question presupposes way too much anthropomorphizing of an AI machine—that is, imagining that it would even be understandable in terms of human categories like “empathetic” versus “psychopathic.”  Sure, an AI might be understandable in those sorts of terms, but only if it had been programmed to act like a human.  In that case, though, I personally find it no easier or harder to imagine an “empathetic” humanoid robot than a “psychopathic” robot!  (If you want a rich imagining of “empathetic robots” in science fiction, of course you need look no further than Isaac Asimov.)

On the other hand, I personally also think it’s possible –even likely—that an AI would pursue its goals (whatever they happened to be) in a way so different from what humans are used to that the AI couldn’t be usefully compared to any particular type of human, even a human psychopath.  To drive home this point, the AI visionary Eliezer Yudkowsky likes to use the example of the “paperclip maximizer.”  This is an AI whose programming would cause it to use its unimaginably-vast intelligence in the service of one goal only: namely, converting as much matter as it possibly can into paperclips!

Now, if such an AI were created, it would indeed likely spell doom for humanity, since the AI would think nothing of destroying the entire Earth to get more iron for paperclips.  But terrible though it was, would you really want to describe such an entity as a “psychopath,” any more than you’d describe (say) a nuclear weapon as a “psychopath”?  The word “psychopath” connotes some sort of deviation from the human norm, but human norms were never applicable to the paperclip maximizer in the first place … all that was ever relevant was the paperclip norm!

Motivated by these sorts of observations, Yudkowsky has thought and written a great deal about how the question of how to create a “friendly AI,” by which he means one that would use its vast intelligence to improve human welfare, instead of maximizing some arbitrary other objective like the total number of paperclips in existence that might be at odds with our welfare.  While I don’t always agree with him—for example, I don’t think AI has a single “key,” and I certainly don’t think such a key will be discovered anytime soon—I’m sure you’d find his writings at yudkowsky.net, lesswrong.com, and overcomingbias.com to be of interest to you.

I should mention, in passing, that “parallel programming” has nothing at all to do with your other (fun) questions.  You could perfectly well have a murderous robot with parallel programming, or a kind, loving robot with serial programming only.

Hope that helps,
Scott