This is an except from Mind Macros 08.
"The way complex adaptive systems work, and the way mental constructs work, problems frequently become easier to solve through 'inversion.' If you turn problems around into reverse, you often think better.
"For instance, if you want to help India, the question you should consider asking is not: 'How can I help India?' Instead, you should ask: 'How can I hurt India?’ You find what will do the worst damage, and then try to avoid it. Perhaps the two approaches seem logically the same thing. But those who have mastered algebra know that inversion will often and easily solve problems that otherwise resist solution. And in life, just as in algebra, inversion will help you solve problems that you can't otherwise handle." — From Poor Charlie's Almanack by Peter D. Kaufman.
Don't ask, how can I improve my life, but how can I worsen my life? Then do the opposite. It's often much easier to find the things we shouldn't do than the things we should. That's why the inversion principle is so effective.
When building an argument, try considering the possibility that you might be wrong and asking, 'how could the opposite be true?' If you had to build a case against your argument, how would you begin disproving it?
"I never allow myself to hold an opinion on anything that I don't know the other side's argument better than they do." — Charlie Munger
Munger's advice runs parallel with a Nassim Nicholas Taleb line in Black Swan I think about often:
"Be confident about what is wrong, not about what you believe is right."