It has been claimed on this site that the fundamental question of rationality is "What do you believe, and why do you believe it?".
A good question it is, but I claim there is another of equal importance. I ask you, Less Wrong...
What are you doing?
And why are you doing it?
I think these two questions are the basic questions of rationality that you should be asking yourself as much as possible. There is this great quote that I have on my desktop:
Only the real determinants of our beliefs can ever influence our real-world accuracy, only the real determinants of our actions can influence our effectiveness in achieving our goals. -- Eliezer Yudkowsky