It's the only Nash equilibrium. The only way everyone can win (and thus, the only way no-one would want to change their guess if they knew all the other guesses) is for all of us to guess a number that is 2/3 of itself: i.e. 0.

ETA: CannibalSmith's explanation is better.

ETA2: AllanCrossman's is even better.

I don't understand how the average guess will be 0. Can you please explain?

I've never been actively part of an online community before, so I'm a bit scared to come along. I do find this group interesting though, so I might come to the next meetup.

I don't mind the place as long as it's quiet, but prefer the format to be casual. Except for Tuesday, any day of the week is fine by me.

If you replace von Mises' intuitions with the particular intuitions neoclassical economics is built from ( to the extent that they differ), then it depends on the particular question you are trying to answer. Market activity is approximated reasonably well by the rationality assumption in a variety of cases. Kahnemann and Tversky's evidence that humans are irrational is certainly strong, but in many cases trying to incorporate this reduces tractability to such an extent that it isn't worth it, or at least we don't know how to incorporate it. A good heuristic is to use rationality for long-run phenomena and when possible, use irrationality for the short run.

I'm considering donating to World Vision UK. Does anyone know much about them?

More generally, is there an easy way to find out how good a charity is? Are there reviews done by third parties?

Eric Drexler.

How should I go about deciding whether to continue this?

With science!

Specifically, the science of John Gottman. Short version: irreconcilable differences of viewpoint are not an intrinsic bar to a long-lasting relationship. The most potent relationship poison is contempt.

I need relationship advice and I trust the wisdom and honesty of this community more than most of my friends. I created a new account to ask this question.

I'm with an incredibly compassionate, creative woman. She excels at her job, which is a "helping profession," and one which I believe improves social welfare far more than most. The sex is outstanding.

But she loves magical thinking, she is somewhat averse to expected-utility calculations, my atheism, etc. She is, by her own admission, subject to strong swings of emotion and at greater than average risk of longer-lasting depression. We love each other but are scared that our differences may be too great.

How would you personally feel about a relationship like this? How should I go about deciding whether to continue this?

Added: We have been together more than 6 months. She has learned a decent amount about my way of thinking, but I have not pushed it on her. I frequently mention how great rationality is (but also mock myself to make sure we're all having fun).

I wish I had confidence that trying to convert her to my way of thinking would have net-benefits for her and for the world long-term, but I don't. Not that I'm convinced trying to convert her is a bad idea on utilitarian grounds either, it just seems risky.

Thanks. That looks like a really interesting body of work. This one on ethics is quite a fun read.

"Plod forever, but never believe you are going to get there."

-Sir Ranulph Fiennes

EDIT: I found this quote funny and strangely motivational, if you read it within the context. But looks like some people really dislike it.