Archive for December, 2010

Page 2

“Even when people haven’t thought everything out in advance, it doesn’t follow that they are necessarily behaving irrationally. Game theory has had some notable successes in explaining the behaviour of spiders and fish, neither of which can be said to think at all. Such mindless animals end up behaving as though they were rational, because rivals whose genes programmed them to behave irrationally are now extinct. Similarly, companies aren’t always run by great intellects, but the market is often just as ruthless as Nature in eliminating the unfit from the scene.”

This is sloppy writing. Note that the author first correctly notices that

“Such mindless animals end up behaving as though they were rational”

He forgets this important qualification in the next sentence

“because rivals whose genes programmed them to behave irrationally are now extinct”.

If they are mindless, as he claims (and I don’t know about that), then it follows that they are not behaving irrationally. Only things agents can behave rationally or irrationally. The sentence needs to be

“because rivals whose genes programmed them to behave as if irrationally are now extinct.”

Page 7

“In acting consistently, Alice may not be aware that she is behaving as though maximizing something we choose to call her utility. But if we want to predict her behaviour, we need to be able to measure her utility on a utility scale, much as temperature is measured on a thermometer. Just as the units on a thermometer are called degrees, we can then say that a util is a unit on Alice’s utility scale.”

A piece of confusing writing. It seems although the author did not read through what he wrote. What might the sentence

“But if we want to predict her behaviour, we need to be able to measure her utility on a utility scale, much as temperature is measured on a thermometer.” [my emphasis]

mean? Surely one measures temperatures using (or with) a themometer. His sentence makes no sense. But we can fix it, like this

“But if we want to predict her behaviour, we need to be able to measure her utility on a utility scale, much as temperature is measured with a thermometer.” [my emphasis]

Now it makes sense, but the analogy is clearly confused. The (correct) analogy that he probably1 tried to make is: it is analogous to measuring utility on a utility scale just as we measure temperature on a temperature scale (e.g. celcius, kelvin, fahrenheit).

Page 19

“Fortunately the paradox-of-rationality phase in the history of game theory is just about over. Insofar as they are remembered, the many fallacies that were invented in hopeless attempts to show that it is rational to cooperate in the Prisoner’s Dilemma are now mostly quoted as entertaining examples of what psychologists call magical reasoning, in which logic is twisted to secure some desired outcome. My favourite example is Immanuel Kant’s claim that rationality demands obeying his categorical imperative. In the Prisoner’s Dilemma, rational players would then all choose dove, because this is the strategy that would be best if everybody chose it.”

“Magical reasoning”? Maybe he meant wishful thinking. A Google search for “magical reasoning” returned only a few thousand results. It could also be that he meant magical thinking but it doesn’t seem so from reading the Wiki page.

Page 26

“Such voting games are only toys. Real people seldom think rational thoughts about whether or not to vote. Even if they did, they might feel that going to the polling booth is a pleasure rather than a pain. But the model nevertheless shows that the pundits who denounce the large minority of people who fail to vote in presidential elections as irrational are talking through their hats. If we want more people to vote, we need to move to a more decentralized system in which every vote really does count enough to outweigh the lack of enthusiasm for voting which so many people obviously feel. If we can’t persuade such folk that they like to vote and we don’t want to change our political system, we will just have to put up with their staying at home on election night. Simply repeating the slogan that ‘every vote counts’ isn’t ever going to work, because it isn’t true.”

Close to what I have been arguing elsewhere. There is more bashing later in the book of defenders of the rational action of voting in national elections.

References to philosophers are often made. The most referred to philosopher is Hume, so fanbois of Hume may want to read the book to learn new subjects that Hume was right about, or had something interesting to say about. Another philosopher referred to is Kant and he is mostly thought to be wrong by the author. Hobbes, Rawls and JS Mill are also mentioned.

Notes

1Because that would fit with the continuing usage of the analogy in the following paragraphs.

Well, one university did and someone wrote a nice open letter to the president of it. It’s worth reading. Bonus points if you can spot the etymological fallacy in it.

A Faustian bargain – Gregory A Petsko

Some science about the inference about sexual interest in the other sex, showing that males infer it much more often than females.

David M. Buss – Handbook of Evolutionary Psychology

Somewhat paradoxically,

“And then there’s Google of course. The search engine that pulled out of China over censorship concerns, announced just a few hours ago that it will censor auto completion on ‘piracy’ related searches worldwide. Apparently censorship is not that bad in some cases.” (TF)

but still not surprising. Should we take a wild guess at how much money Google earns from copyright infringement that happens on their services (i.e. primarily Youtube)? Holy shet a lot!