Examples of Rationality Techniques adopted by the Masses

Hi Everyone,

I was discussing LessWrong and rationality with a few people the other day, and I hit upon a common snag in the conversation.

My conversation partners agreed that rationality is a good idea in general, agreed that there are things you personally can do to improve your decision-making. But their point of view was that, while this is a nice ideal to strive to for yourself, there’s little progress that could be made in the general population, who will remain irrational. Since one of the missions of CFAR/​LW is to raise the sanity waterline, this is of course a problem.

So here’s my question, something I was unable to think of in the spur of the argument—what are good examples of rationality techniques that have already become commonly used in the general population? E.g., one could say “the scientific method”, which is certainly a kind of rationality technique that’s going semi-wide adoption (though nowhere near universal). Are there any other examples? If you send a random from today back in time, other than specific advances in science, will there be anything they could teach people from the old days in terms of general thinking?