I think you're conflating "ordinary research" and "applied research". "Big thinking" is often pure research, and pure research is just as valid a topic for a P

I think you're conflating "ordinary research" and "applied research". "Big thinking" is often pure research, and pure research is just as valid a topic for a PhD as applied research is. There's not a lot of other opportunities to spend a significant amount of time working on the one thing. > Maybe the big thinking should be done -- as it is currently -- by people who have already demonstrated that they can do all that very well. I completely dispute this. I would bet that historically, the majority of "big thinking" has been done by people who are not already well established. In fact, I think there's a fallacy that "big thinking" somehow comes from accumulated experience. I would argue that "big thinking" is actually a different kind of thinking, one that requires you to have that kind of thinking rather than a wealth of experience. [EDIT: there seems to be empirical evidence that having a wealth of experience tends to prevent people from coming up with (good) "big ideas". And since this is Hacker News, think about this in terms of technology and startups. Is it usually older people or younger people who tend to come up with the game-changing tech developments?]