Paul Graham: What You Can't Say. “The most important thing is to be able to think what you want, not to say what you want. … Draw a sharp line between your thoughts and your speech. Inside your head, anything is allowed. … But, as in a secret society, nothing that happens within the building should be told to outsiders.” [Hack the Planet]
More provocative thinking from Paul Graham. Some bits and pieces that particularly caught my eye, although it's all worth reading and thinking about:
A good scientist, in other words, does not merely ignore conventional wisdom, but makes a special effort to break it. Scientists go looking for trouble. This should be the m.o. of any scholar, but scientists seem much more willing to look under rocks. 
Why? It could be that the scientists are simply smarter; most physicists could, if necessary, make it through a PhD program in French literature, but few professors of French literature could make it through a PhD program in physics. Or it could be because it's clearer in the sciences whether theories are true or false, and this makes scientists bolder. (Or it could be that, because it's clearer in the sciences whether theories are true or false, you have to be smart to get jobs as a scientist, rather than just a good politician.)
Argue with idiots, and you become an idiot.