In the podcast between Spencer Greenberg and Buck Shlegeris, Taking pleasure in being wrong, Buck says:
I think that when you are learning subjects something that you should really be taken your eye out for is the simplest question in the field that you don't know the answer to.
I think a lot of the time people try to learn physics or something and their approach is as quickly as possible to answer hard questions about complicated subjects. And I think that's what I thought was cool when I was younger. They delighted at questions that were at the limit of fanciness that they could possibly answer and it feels to me now that it is a lot more productive to seek out questions that are as simple sounding as possible while still being really hard to answer. Or that still demonstrate that there's something you don't understand about the subject.
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It seems like we should be seeking out these most basic questions in the hope of finding holes in the foundation of our knowledge.
If we apply that approach to applied rationality, what questions do you have that seem to be simple but where you don't know the answer?
"I don’t like spinach, and I’m glad I don’t, because if I liked it i’d eat it, and I hate it."
Every new experience may change your preferences. Seeking out new experiences will predictably have this effect. Openness to experience requires openness to seeing your preferences changing, even if you do not know in what direction. This has been going on since birth, as no-one is born with the preferences they will have as adults. There is a process by which they develop, which does not, or at least need not, stop on reaching adulthood.