I was surprised to learn Bryan Caplan beliefs in Free Will. He also likes to bet on his beliefs.

So here's my plan for money pumping Bryan Caplan or other libertarians who confused themselves about free will to the point where they are arguing, by definition, that the causes of a choice cannot have a causal explanation or not be "free": get him to play successive rounds of rock-paper-scissors against world champions for small amounts of money. Of course, this would only work as long as he does not learn to run some pseudorandom number generator inside his head. But in my experience, most people are terrible at rock paper scissors and don't run a random strategy. So if free will were a thing, would that imply people good at rock-paper-scissors have more of it than others?

New Comment
9 comments, sorted by Click to highlight new comments since: Today at 4:36 AM

Caplan is definitely aware that people are at least somewhat predictable at least some of the time. Why would his beliefs be challenged by the existence of rock-paper-scissors players who are good at predicting their opponents' choices? I'm not playing dumb here, it really doesn't make sense to me.

(He also strikes me as the sort of person who, given sufficient incentive, would run a randomised strategy. But that's a sidenote.)

Well here is what Bryan said in the 80k Podcast about what would change his mind:

Now the thought experiment is to tell me that unconditional prediction — and you should be able to go and tell me the prediction in such a way that it incorporates all my reactions and secondary reactions and so on, all the way to infinity. And now guess what I’m going to do? I’m going to do the opposite of what you said I’m going to do. All right? Again, it’s not ironclad, and I know there’s a lot of people who say, no, no, no, feedback loops, and it doesn’t count. But it sure seems like if determinism was true, you should be able to give me unconditional predictions about what I’m going to do. And then intuitively, it seems like I could totally not do them.

There is of course the obvious way to make this work by making a prediction that is so close to the future, that you don't have enough time to change your mind, thus rock-paper-scissors. I honestly don't know how this would fit into his worldview.

Caplan's thought experiment does seem confused to me, so I'm not sure exactly what his position is and I'm not confident that it's coherent. But his being told of the prediction in advance is a very deliberate feature of the thought experiment, so I don't think you can make it testable by removing that.

As for whether being owned at RPS should surprise him, or should in general shake the confidence of a free-will libertarian -- I can't imagine anyone having failed to notice that better-than-chance predictions of human behaviour are often possible, so I still don't see why a direct demonstration of this would threaten their beliefs. Any thoughtful free-will libertarian must have a theory that is (believed to be) compatible with partial predictability.

The question is whether he would break the prediction. He can certainly imagine breaking it, in principle, but would he actually break it? That's something that a thought experiment can't possibly address. Since we don't yet have any way of predicting human behaviour to the required extent, we can't actually conduct the experiment.

Of course, the thought experiment is rubbish. It applies just as well to a deterministic computer program that prints "What will I print next?", reads the input, and then print something else (e.g. by printing "Fooled you!" to anything except "Fooled you!", to which it prints "Nope."). Would Bryan argue that this program is not deterministic? I'm not a foolproof Bryan-predictor, but I'm going to predict "no".

"But it sure seems like if determinism was true, you should be able to give me unconditional predictions"

This sounds like his confusion could be resolved by someone explaining to him what determinism is.

There is obvious class of predictions like killing own family or yourself and such prediction are good example of what absence of free will feels from inside. There are things I care about, and I am not free to throw them away.

Good luck! You'll need it.

He seems to have been influenced by Ayn Rand. She also uses the "law of causality" to mean what other people mean by "determinism".But determinism isn't defined as "every effect has a cause", it's defined as "every event has a cause". How can Caplan deny that his choices are events? of course, if he is a dualist he can deny that they are physical events....

His observation that he is not aware of the source of his choices is subjective. His choices are caused by neural activity, whether he is aware of it it or not. But that doesn't prove determinism, because knowing that there is some sort of physics behind decision making isn't enough to show there is deterministic physics behind it. Neither naive subjectivism ,nor generic physicalism is enough to solve the problem.

I like the framing. Seems generally usefwl somehow. If you see someone believing something you think is inconsistent, think about how to money-pump them. If you can't, then are you sure they're being inconsistent? Of course, there are lots of inconsistent beliefs that you can't money-pump, but seems usefwl to have a habit of checking. Thanks!

New to LessWrong?