By "success" I meant successfully doing useful research/getting money to charity/spreading rationality. Which I think is closer to "value creation" or "positive externalities" than what you seem to be calling "success," namely personal welfare.
Actually, I didn't mean only personal welfare. What I wrote certainly applies to career success that brings money and power, but also to all other kinds of accomplishments that are commonly seen as worthy and admirable.
In fact, often it's even more difficult to judge the latter accurately. People are used to arguing whether someone who profits from success has deserved it, and they're normally willing to listen to someone who argues either way in some particular case. However, when it comes to accomplishments that are seen as selfless idealism, it's much more difficult to criticize those without being perceived as weird or malicious. This despite the fact that these can be about signaling games, rent-seeking, and unaccounted externalities just as much as any for-profit endeavor, no matter how admirable and high-status they are commonly perceived.
I have been having some difficulty deciding what to do with my life. I'm not really ashamed or surprised, because the problem seems extremely difficult and worth getting right. I still don't really know. Here are some of my options, though I wouldn't be surprised if what I end up doing is not on the list. I thought I would share to elicit advice, to give some context to some of my recent remarks, and maybe to provide comparison for people in similar situations.
1. Research
I could do research in a university, or in a private research lab. Many fields have at least a few questions that seem important and interesting.
A. Theoretical Computer Science. I could work on collaborative learning, recommendation and reputation systems, distributed protocols, or anything else that might assist collaboration in the future.
B. AI / Computational Cognitive Neuroscience. I could work on algorithms for inference and planning, to increase the probability that we develop comprehensible or human-like AI before something horrible happens (like developing incomprehensible strong AI).
C. Neuroscience. I know almost nothing about this field, but technology for measuring and interfacing with the brain appears to be important and developing rapidly. I don't know how hard it would be to start working in the field, but I suspect that the connection to computer science is strong enough at MIT that it wouldn't be impossible.
2. Start a company
This seems way harder, but I am sufficiently arrogant and risk-neutral that I consider it a reasonable option. In particular, this is what I would do if I decided that making money as efficiently as possible and giving it away
A. Tech company. If I had to guess based on the currently available evidence, I would guess that this is the way to maximize my expected earnings.
B. Online Education. I would like to take a shot at designing materials for online education of smart, significantly underserved, high school students.
3. Cooperate with Other Rationalists
A. Work for a rational charity. Self-explanatory. Probably worse than earning a lot of money and giving away.
B. Start a rational charity. Probably worse than supporting an existing charity.
C. Work for a rational start-up. Can't really arrange this one; but optimistically it could happen if you were prepared (someone else does 2).
4. Be a Hobbyist
I could also simply try and earn a living as quickly as possible (rather than making as much excess as possible, or having a more structured way of doing good) and do work on the side. I don't think this is a good idea.