Smarter/more rational/more logical people self-select themselves into the math/hard sciences to begin with (but they also have peers who aren't likely to subscribe to certain irrational belief systems). I've never seen any real evidence that math/physics majors have ever become more rational as a result of their training (they're basically taught material as if it were completely inapplicable to the real world). Transfer generally doesn't seem to happen like that.
Personally, I believe that philosophy and economics are probably the best fields to train rationalists, although there are subsets of CS and statistics (Pearl's causal modelling) that are also excellent for training rationalists. That being said, much of the philosophy curriculum does consist of ancient/medieval bullshit, so while it can definitely help a rationalist think, its material isn't the best use of a rationalist's time.
What would also work, is being a CNS (or economics) major at Caltech, or a Brain & Behavioral Sciences major at MIT
Personally, I believe that philosophy and economics are probably the best fields to train rationalists, ...
Rationality training should not be based on disciplines full of confusion. Philosophy is practically defined as a set of questions (so far) so confusing that they cannot be properly addressed by some branch of science. Economics is closely tied to politics and has (because of many practical reasons) a very limited possibility for empirical testing. They may be good disciplines to work on for an already advanced rationalist - and there are aspects o...
A Wall Street Journal article by Harvard professor of government Harvey Mansfield claims that the social sciences and humanities are inferior to the sciences. The article implicitly urges undergraduates to major in science. From the article:
Do you agree with this? As a game theorist I probably have a rather biased view of the situation. It's certainly true that the ideal of the scientific method is vastly better than the practice of economists, but I think that majoring in economics provides better training for a rationalist than majoring in any of the sciences does.
Economics explicitly considers what it means to be rational. Although it infrequently considers ways in which humans are irrational, I'm under the impression that the hard sciences never do this. Furthermore, because economists can almost never perform replicable experiments we have to rely on what everyone in the profession recognizes as messy data; therefore we’re far more equipped than hard scientists to understand the limits of using statistical inference to draw conclusions from real world situations. Although I have seen no data on this, I bet that a claim by nutritionists that they have found a strong causal link between some X and heart disease would be treated with far more skepticism by the average economist than the average hard scientist.