Tuesday, December 2, 2014

Uses for cloned woolly mammoths

The possibility of cloning woolly mammoths has been back in the news lately. Someone I know asked what they would be good for:
I have compiled a list. Thanks to Aliya Vasylenko for her contributions.
  • Wool
  • Easier to get across Alps than elephants
  • Men's rights activists can fight them to boost their self-esteem
  • Zoo attraction
  • Food
  • Episode of Inside Nature's Giants
  • Polo variant for cold climates
  • Replacement for elephants for when they go extinct
  • Ivory source
  • Decorative hairdressing subject for animal shows
  • Pet therapy for the elderly; especially effective due to unique combination of wool and trunk
  • Riding through Siberia
  • Bookmobile for those hard to reach areas
  • Breed with elephants to produce mammophants
  • Potential for musical talent, if they're anything like elephants:


Sunday, November 9, 2014

Bubbles might not always be silly



I’ve been listening to NPR’s Planet Money podcasts recently, and a couple of days ago I listened to this one about economic bubbles. Bubbles are what some people call it when the price of something goes up and up and then crashes, and often you could kind of see that a crash was coming sooner or later. Sometimes people say that people were silly to spend all the money buying the thing when it was expensive. The podcasters spoke to Nobel Prizewinner Robert Schiller, who thinks the people driving up the price were being silly, at least sometimes. They also spoke to Eugene Fama, who shared the prize, and thinks that people aren’t being silly; you just can’t tell when something’s a bubble and when it isn’t. It was all pretty good-natured. Schiller and Fama shared their prize with another guy called Lars Peter Hansen, if you’re interested.

Now, regular readers will probably have noticed that one of my hobbies is duplicating the intellectual efforts of other people, and today is no exception. I had a bit of a think about bubbles. Silliness is hard to model, so I tried to think of a kind of situation where the price of something might go up and up and then crash, even though the investors are going into it pretty much with their eyes open.

Here’s what I came up with. You have some kind of commodity which is generating a pretty good income at the moment, but you don’t know how long it’s going to carry on doing it. Maybe it’s a tulip farm and at the moment people are paying top dollar for tulips, but you don’t know how long the craze is going to last. Maybe it’s a share in Justin Bieber’s record company. How do you value something like that?

Well, you need to quantify how long you think it’s going to last. Maybe you think it’ll last something between one and ten years, and your credences are distributed equally over one year, two years and so on up to ten years. That lets you put an expected value on it. Now, if you’re a Bayesian and it’s still popular after a year, you’ll think it has between one and nine years left, and your credences will be equally distributed over one year left, two years left, and so on up to nine years. This lets you put a new expected value on it, and it’ll be lower than it was a year ago. So the expected value of Bieber's tulip farm goes gradually down, until sometime during this decade people lose interest in his tulips and the value of the farm crashes. That’s not a bubble. In a bubble the price is meant to go up until the crash.

Suppose you model your uncertainty about how long the craze will last differently. Instead of thinking how long it’ll last, you think about what the craze’s half-life is. Maybe you think it’s got a half-life of between one and five years, and you distribute your credences equally over half-lives of one year, two years, and so on up to five. (The craze’s half-life is the length of time in which it has a 50% chance of ending. In general, if the half-life is h years, the chance of the craze surviving the next h*n years is 0.5n.)

Now what happens if the craze is still going after a year? Well, that was more likely to happen if the half-life was long, so you end up redistributing your credences to make a long half-life more likely and a short half-life less likely. This means that after a year the value will go up. And it’ll keep going up until the craze ends. That’s got the rise-rise-crash character of a bubble, but nobody has had to do anything silly. This is true even though it’s predictable that the price will rise until the crash, and even if the investors are all sure the crash is coming sooner or later. I guess that if prices going up and up and then crashing was always this kind of phenomenon, that would mean Fama was right and Schiller was wrong. But I don’t really know; I just listened to one Planet Money podcast. (Well, actually I’ve listened to about a hundred Planet Money podcasts, but only one was about bubbles.)

Is this a reasonable way of dealing with uncertainty about how long a craze will last? Sometimes, it probably is. People have been into Barbie dolls for longer than they’ve been into Loom bands, and this inspires confidence that Barbie will still be around after Loom bands are gone. The longer Loom bands stick around, the longer they might seem to have left. When something’s been around as long as Barbie and Coke, it’s hard to imagine it ever going out of fashion.

So here’s another question: do real commodities exhibiting the price-rise-then-crash phenomenon fit this model? Well, no. Not exactly. The dotcom bubble was based on a load of companies which often weren’t bringing in much income at all at the time (right?), with investors betting on future income. But I think that can still fit into the model. Even if you only projected that the income would come, say, five years into the craze, the expected value still goes up as the probable half-life goes up, and the probable half-life carries on going up until the craze ends (or until a bunch of similar crazes end). So maybe the dotcom bubble was like that too. And the tulip bubble. Anyway, I recommend the podcasts.

Thursday, November 6, 2014

Change your life now, stupid

There’s a certain kind of atheist who doesn’t have a lot of sympathy for religious folk. They either read or write books by people like Richard Dawkins, Sam Harris and Christopher Hitchens, they call themselves sceptics or rationalists or humanists depending on how closely they follow the trends, and they basically think religious people are being silly.

I’m an atheist too, and I’ve got some sympathy for this way of thinking. Suppose you’ve got a pretty vanilla epistemology, and you apply the same kinds of critical thinking to the claims of religion that you apply to claims about miracle cures, the Rev James Jones, faster than light neutrinos and the garment industry in Mauritius. From that point of view it’s basically impossible to persuade someone else of much in the way of religious claims, and unless you’ve had some pretty out-there experiences you’ll have a hard time becoming very certain of them yourself too. Now, you might say that if you applied these kinds of critical thinking to everything then you’d end up believing not much at all, and if you’re jazzing up your epistemology anyway you might as well salvage your religion. That’s a caricature of Alvin Plantinga’s line – I haven’t read much of his work on this and don’t know how accurate it is – but maybe there’s something in it, or in something like it. But if you don’t buy into it, and I can see why people don’t, then most of the claims of religion can come over as pretty tenuous, and the believers can seem pretty silly.

The kind of atheist I’ve got in mind responds by saying all the billions of religious people should wise up, stop going to church, stop praying, stop believing that there’s been divine intervention in human affairs, evolution, cosmology or whatever, and just become straight-up atheists. And in fact, about twelve years ago I did just that. I stopped going to church, stopped praying, stopped attributing things to divine action and went from committed Christian to convinced atheist. I went back and forth a bit, and the process took about a year.

So if I can do it, why can’t everyone? Well, I think that what these unsympathetic atheists are disregarding is the fact that they’re asking people to make  some really radical changes in their lives, and making radical changes in your life is difficult! Sure, they’ve heard the sceptics’ little arguments, and sure, they can’t really say what’s wrong with them, but so what? If you’re going to radically change your life in response to an argument, you’d better be damn sure it’s a good argument, and who has the time to put in that much thought? And if even they did put in the thought, let’s not forget that some of the greatest minds in history have spent an enormous amount of time thinking about pretty much these same issues, and a lot of them come out of it disagreeing with Dawkins. The so-called new atheists might like to pretend there’s no serious debate here, but this only indicates that they haven't got the expertise or the inclination to engage with it. The debate's there, it's serious, and there are smart people on both sides. One might try to claim that one side isn’t arguing in good faith, but I don’t think this claim can be made in good faith except from a position of extreme ignorance.

So anyway, I’ve got a lot of sympathy for people who don’t want to radically change their lives in response to a simple argument. And in fact, I think this follows a general pattern: I try not to be unsympathetic towards people for not doing something that is very difficult to do, and as I said, radically changing your life is very difficult. Of course, it’s sometimes very difficult to be sympathetic even with people in a difficult position, and I try to be sympathetic with people who don’t follow this pattern.

Perhaps people’s sympathies could be jiggered along a bit by considering another simple argument for radically changing your life: Peter Singer’s arguments about charity. Regular readers might remember me writing about these a couple of times before. You’d save the life of a child drowning in front of you if you could do it at a small cost to yourself, so why not save the life of a child dying of famine or diarrhoea or whatever far away? You can argue it back and forth, but the fact is that people are dying every day who wouldn’t be if someone middle class spent less time on Amazon and more time on Givewell. If you’re middle class, then today you could be that person! But if you follow Singer’s arguments through, you end up giving away most of your disposable income, and that’s hard. Or at least, it seems to be hard. So, what have the atheists’ arguments got that Singer’s haven’t? If you’re so smart, why are you rich?

Saturday, October 25, 2014

Piketty and Paul



Regular readers will know that I’m pretty leftwing, but that doesn’t mean I’m blind to the fact that people respond to financial incentives. Sometimes people on the left get viewed as thinking we should act as if financial incentives didn’t really affect people’s behaviour much, and if this idealization results in a bit of inefficiency then you just have to suck it up. At the extreme that sort of thing might lead to something like communism, but maybe some lefties who aren’t communists are guilty of the idealize-and-suck-it-up mindset too. But I try not to be.


Given this, I think it’s a bit of a shame that we pay people to be unemployed, even though we don’t want people to be unemployed, and we charge people for earning money, even though we want people to earn money. (In case you can’t tell, I’m talking about unemployment benefits and income taxes.) The thinking behind these prima facie wacky policies is that if you don’t pay people to be unemployed then the unemployed will starve, and if you don’t charge people for earning money then you won’t be able to raise enough money to run the government. In the past I’ve expressed an interest in the idea of replacing unemployment benefits with a universal basic income that you give to employed people as well as unemployed people. But what about income tax? Is there a better way to raise money?


First let’s remind ourselves why income tax is such a shame. Suppose I’m rich and I’d rather have Lancelot Capability Brown landscape my garden than have £100,000, and Brown would rather have £80,000 than not landscape my garden. In an ideal world, I’d pay him somewhere from £80k-£100k to landscape my garden: it's a win-win situation. But if there are income taxes, the state will probably charge us so much to make this transaction that it isn’t worth either of our while to make it. I don’t get my garden landscaped, Brown doesn’t get his money, and the state doesn’t get anything out of it either. That’s no good. And everyone knows it’s no good, but we can’t think of a better system, so like the hypothetical lefties I mentioned earlier, we just suck it up. Where income taxes apply, people don’t just work when they value their time and labour a bit less than the employer does; the employee has to value it a lot less, so they'll still both be happy with the deal once the income tax is factored in.

What’s the alternative? Well, on the face of it, maybe it’s wealth taxes. If the wealth’s going to get taxed at the end of the year whether I have it or Brown has it, then transferring it to him doesn’t cost anything, and the inefficiency goes away. If I value his time and labour more than he does, we do the deal. I don’t know whether libertarians like wealth taxes – they sometimes seem to talk about sales taxes as better than income taxes, which I don’t really get – but I think there’s a case that they should. Libertarians don’t like the state charging people to engage in harmless activities, and that includes employment. With a wealth tax, the state’s taking some of your money anyway, but for the money you’re allowed to keep, you’re equally allowed to give it away. I’m not a libertarian, but I like freedom as much as the next person, so this seems like a nice feature. There’s also a case that libertarians shouldn't even see wealth taxes as a necessary injustice, because the state is the body enforcing continued property rights over people’s wealth and so it’s only fair for it to take a cut. (I sometimes wonder what would happen if big countries insisted that tax havens bear the burden of enforcing the property rights and contracts officially under their jurisdiction. Maybe Luxembourgish police officers would have to travel the world chasing up second-hand books people bought on Amazon and never received.)


So what’s the problem? Why are modern democracies nuts for income tax, while often having no wealth taxes at all? (Unless you count inheritance tax, which is a bit like a crude wealth tax.) Maybe it’s because they wouldn’t work the way I’m imagining, which is perfectly possible; my understanding of this stuff is pretty basic. Or maybe it’s because wealth taxes would hit the wealthy more than income taxes do, and so they use their wealth to stop it happening. Or maybe it’s because income tax is the only one people can’t rampantly avoid. I remember when Thomas Piketty’s book came out and he was pushing wealth taxes, he thought they’d need a lot of multilateral co-operation, and maybe he was thinking about avoidance. If that’s all it is, though, it seems a real shame, and economic libertarians are arguably the people who should be most bothered by it. Maybe if Rand Paul becomes US president then something will be done.

Thursday, September 25, 2014

Ripped at the seems



I don’t often have ideas about epistemology. Longtime readers may remember me talking about epistemic virtues of personal concern, and for a while I misguidedly tried to push the idea that Gettier was wrong about knowledge not being justified true belief. Recently though, I was listening to Peter Adamson’s excellent podcast series on the history of philosophy, and when he got to the ancient sceptics I started thinking about epistemology again. Here’s my idea.

In epistemology, there are (of course) lots of debates, arguments and projects about knowledge. For example, sceptical arguments say that nobody knows anything, at least in some domain of inquiry. There’s also a kind of Kantian project that starts instead from the fact that we do have knowledge, and asks how everything else might be set up to make that possible. My idea is to have analogous debates but replacing “S knows that P” or “I know that P” with “it seems to S that P” and “it seems to me that P”. This goes off in a few directions.

First, there’s a sceptical argument that nothing seems to you to be true other than that you’re having the experiences you’re now having. Just as with knowledge, you can argue for this by considering sceptical scenarios, such as that you’re a brain in a vat hooked up to a virtual reality machine (a bit like the Matrix), or that you’re dreaming, or that Descartes’ evil demon is tricking you. Now, maybe you don’t know that these things aren’t happening, but at least they seem not to be happening, right? Well, that isn’t obvious. I mean, what would these things seeming to be happening be like? It’d be just like it is now. So maybe it actually does seem exactly like you’re in the Matrix, apart from the greeny-grey colour filter which we can ignore for present purposes. At least, it seems you’re in the Matrix just as much as it seems you’re in the regular external world. The only thing these seemingly-true scenarios have in common is your experiences, so maybe all we can really say is that you seem to be having the experiences you’re having now.

For fans of modal logic, I guess this is an understanding of seeming according to which something seems to be true iff it’s true in all possible worlds where you’re having the experiences you’re actually having. Maybe you could try replacing “all possible worlds” with “close possible worlds”, producing a kind of externalist understanding of seeming which is a bit like Nozick’s understanding of knowledge. I wonder if it’d be open to similar objections to Nozick’s view, including the absolute pummelling of it that Kripke published in 2011.

We don’t have to revise our understanding of seeming that way, though. We can revise it a different way which allows some things other than our experiences to seem to be happening, while avoiding the objections to Nozick's view. We can think about what seeming, and people, and the world would have to be like for there to be non-experiential seemings. This is like the Kantian project I mentioned before. Maybe biology can help. To me it, er, seems that this might be more plausible than coming up with a biologized conception of knowledge that lets us have what we want, because knowledge is a more normatively loaded concept. Being lucky enough to have cognitive biases might make things seem to be true, but could they make you know things? I don't know. Maybe we can construct a plausible naturalized epistemology around seeming which isn't vulnerable to the same normative criticisms as one constructed around knowledge.

If you’re still on board at this point, there are a couple of ways you might want to go. One is to be like Sextus Empiricus (I think), and never make claims about knowledge: you just say how things seem to you. You might think a position like that was unstable, because when you assert the position you’re committing to knowing it, not just to it seeming to be true. I don’t think that’s necessarily right though: we could posit a speech act which is correct when its content seems to you to be true, as assertions are (let’s say) correct when you know their contents. (More boringly, we could just allow that we do know how things seem to us.) We could investigate what kind of logical norms would apply to such a speech act. Maybe you can’t know contrary propositions, but can contrary propositions both seem to be true? If P&Q seems to be true, does that mean P seems to be true as well? There’s room for productive debate about those and similar questions. I think it’s perfectly possible that an epistemology constructed around seeming might be stable in a way that full-on scepticism of a kind which doesn’t allow any assertions or put anything in assertion’s place isn’t stable. The seeming-based epistemology might not be stable either, but I’d like to know, and if it is, and it’s what the ancient sceptics had in mind, that would be very cool.

Maybe we don’t have to content ourselves with seeming, though. One way epistemologists sometimes frame the problem of scepticism is as the problem of getting knowledge from non-knowledge. Maybe a beefed-up notion of seeming can give us some traction on this. That’s because if something seems to be true, that’s plausibly a defeasible reason for believing that it is true. So from seeming, which isn't knowledge, we get reasons for belief. Can we get all the way to knowledge? Maybe we could with a bit of ingenuity. Mark Schroeder wrote a book called Slaves of the Passions in which he tried to reduce all of our normative concepts to the idea of facts being reasons for people to do actions. I don’t actually think he succeeds, but it’s impressive how far he gets. (It really is a fantastic book; I can't praise it enough.) And if you can construct a bunch of normative concepts out of ‘P is a reason for S to do X’, maybe you can construct some epistemic concepts out of ‘S has a reason to believe P’. That would also be very cool.

Saturday, August 30, 2014

Are Nato the bad guys?

Today there is a Nato summit going on in Newport, Wales, and some people are protesting against it. Here are some of them:


I know it looks like they're protesting in support of Palestine, whose main antagonist (Israel) isn't in Nato, but I'm assured that it's an anti-Nato protest. 

At the same time, there are Russian tanks invading Ukraine. You can watch a video of that happening here.

Now, you'll notice that CND tweeted the picture of the protesters, and that's because they agree with them; they've been encouraging their Twitter followers to go to the protest for a while. As I understand it, they think Britain should unilaterally leave. They think Nato makes the world less safe from wars. I agree with CND (which stands for Campaign for Nuclear Disarmament) about nuclear disarmament: I'm really not persuaded that nuclear weapons help anybody except the people who make them and the North Korean government. I'm also pretty anti-war in general, and Nato does participate in wars. But I'm not sure I agree with CND about Nato.

They make their case against Nato here. Basically, they have these problems with it:

  • Nato was set up to defend against the USSR, which doesn't exist anymore.
  • Since the USSR broke up, Nato has expanded to include former USSR members and allies, and is trying to include even more, which winds Russia up and makes them invade Ukraine.
  • Now that the Cold War is over, the Devil is making work in Asia and Africa (Libya) for Nato's idle hands, instead of Nato just focusing on defence.
  • America bullies Nato members in Europe into hosting nuclear weapons, which violates the Nuclear Non-Proliferation Treaty.

Now, on the whole I've thought that Nato's expansion into Eastern Europe was a fine thing which allows peoples formerly under the Soviet boot to be relatively confident of peace and self-determination. The central idea of Nato is that if one of the members is attacked then all the members treat it as an attack on themselves. Since the combined military force of Nato is huge, this makes it a pretty big step invading a Nato member. While Russia can invade Ukraine now and invaded Georgia in 2008 without starting World War Three, they seem to let the Baltic states and the rest of the eastern part of Nato get on with joining the EU and whatever other unRussian activities they fancy. Turkey (in Nato since 1952) also seems to have been quite safe for a country with such nasty neighbours (USSR, Assad, Saddam Hussein, Iran). From this point of view, Ukraine's current crisis doesn't result from Nato expanding too much, but from it not expanding enough.

Now, while it's obviously nice if peoples can be more confident of peace and self-determination than eastern Europe was when the USSR existed, this isn't CND's main concern. CND, naturally, is most concerned about protecting humanity from annihilation in a nuclear war. I think that's the concern behind most of their objection to Nato. So, are they right? In my zeal to protect the people of Latvia, am I supporting an institution which risks killing us all? Well, let's look at CND's objections to Nato.

"The USSR doesn't exist anymore."
 
It is true that the threats faced by Nato members aren't exactly the same as they were when Stalin and his successors were around. It's also true that around the start of the 1990s Russia became much less interested in controlling its neighbours. If Gorbachev or even Yeltsin was still in charge of Russia, maybe there still wouldn't be such a problem. But Putin and whoever else wields the power in Russia are quite obviously very interested in influencing and annexing parts of their neighbours. The Cold War is over but Russia is still obviously a threat to eastern Europe. It's invading it right now.

"All this Nato expansion is just winding Russia up."

It isn't easy to adjudicate the extent to which Russia's current aggression results from being wound up by Nato expansion. Maybe Putin wants to grab as much of Ukraine as possible before it joins Nato and becomes untouchable. Maybe he wants to be the most successful, powerful politician he can be, and that means grabbing places that are vulnerable. Either way it seems pretty harsh on the Baltic states to leave them vulnerable for fear of what Russia will do somewhere else.

"Nato members end up having to go along with US aggression"

The point about sucking countries into America's military adventures isn't easy either. One thing to point out is that how involved countries got in Iraq, Afghanistan and Libya wasn't determined by whether they were in Nato. Another thing is that you can't really say that military action which is conducted under the auspices of Nato now wouldn't happen if Nato didn't exist. You might even think it's better if countries that suck up to America by joining in with their military adventures at least get a mutual protection pact out of it, rather than being left in the lurch if Putin comes a-calling at the wrong part of the American election cycle. But it's probably true that Nato gives America a list of ready-made allies who feel pushed into joining in with America's wars, which often lie somewhere on the spectrum between catastrophic foolishness and racially aggravated mass murder.

"America is violating the non-proliferation treaty."

The last point, about making non-nuclear countries host nuclear weapons, isn't really something I know much about. I don't know why they don't just tell the Americans to take their WMDs elsewhere, or whether the reason has anything to do with Nato. It does however seem like pretty small potatoes. The risk of Russia invading an undefended Latvia seems a lot more real than the risk of someone accidentally setting off a nuclear bomb. People nearly accidentally detonate nuclear bombs every few decades; Russia actually invades an ex-Soviet state every few years. And if we do all die in a nuclear war, I'm not convinced it might be because the missiles were based in Germany.

I guess it might seem like I'm pretty pro-Nato, but I wouldn't go that far. I don't know enough about it, as well-informed readers can presumably tell. But I don't think CND have made the case well enough, and I think they're focusing too much on the threat of nuclear war and ignoring the rest of the picture. I'm not saying that Nato's wonderful or even that all things considered Britain shouldn't leave, but I am saying that if you were protesting in Newport and you don't live somewhere like Latvia or somewhere else like Ukraine then maybe you should think about how lucky you are.





Monday, August 25, 2014

A good day to create the universe


Ancient and medieval cosmologists used to wonder whether the universe had always existed, or whether it had come into existence at some particular time in the past. (I don’t think it had occurred to them that it might have existed throughout an open temporal interval bounded at the start but with no first point.) One of the arguments in favour of the universe always having existed was based on what philosophers call the Principle of Sufficient Reason. The idea was that if the universe had come into being at some particular time then there should be some reason why it came into being at that time rather than at another. This worry can be beefed up a bit if you think that God created the universe: even if random events can happen for no reason, it seems odd to think God would make a decision for no reason. Of course it’s odd to imagine God paralysed between two bales of hay like Buridan’s ass, but it’s actually kind of hard to explain exactly how arbitrary divine decisions are meant to work.

One option in the face of this problem is to say that the universe has always existed, and if you want to put a theological spin on that then you can say that God constantly acts to keeps the universe going, or that it depends on him in some other way besides being created at a particular time. An alternative is to say that there was no such thing as time independent of the universe being created: God’s act of creating the universe also created time itself. That option goes back a long way, but it’s probably harder to square with a pre-modern understanding of time than with the picture offered by contemporary physics, so people still fretted about it. It’d be nice to have an explanation for why one time to create the universe might have been better than the others, so that’s what I’m going to offer today.

When philosophers of religion aren’t fretting about cosmology, they’re usually fretting about free will and divine foreknowledge. If God knows this morning what I’ll do this afternoon, how can my actions this afternoon be free? Well, one option put forward by Boethius is to say that, just as seeing something happening now isn’t making it happen, seeing/knowing about something happening in the future doesn’t make that happen either. We control what we’ll do, and that determines what God (correctly) believes we’ll do. If that’d be a case of backwards causation, then there’s backwards causation. (Backwards causation? Wouldn't that mean time travel is possible? Well, yes: with God all things are possible.) Now, if you take this line on free will and divine causation, then I can help explain why God created the universe when he did.

The idea is that, at each time while he was waiting to create the universe, God knew which free choices the people would make if he created the universe then. The same initial conditions could lead to different outcomes – that’s what indeterminism is – and at each time God knew which outcomes he’d get if he put his initial conditions in place then. He waited until the time that would lead to the best choices, created the universe then, and here we are.
                                                                                                        
For someone with the prior commitments I have about time, free will, the existence of God and the principle of sufficient reason, this puzzle is basically moot. But a puzzle being moot never stops philosophers trying to solve it. And if you have different commitments, maybe my idea can help you more substantively. What do you think?