I would like to counter the opinions that claim that the author should use the term "ignorance" rather than "stupidity". IMHO, the inadequacy that one feels during research does not arise from not knowing the answer, it is a result of not being able to figure out how to approach the problem and reaching an answer. More than this, most of the time you do not know what the appropriate question is.<p>This is not ignorance, sometimes you simply cannot weave the threads of knowledge you have to reach a pattern. Of course if you have more threads, your job becomes easier; and at some low level of knowledge you will have nothing interesting to ask, but this is not the major difficulty in completing a Ph.D. thesis, at least in my experience (which is in physics/astronomy).<p>This is what the author is talking about, it is not "knowledge" that is lacking, at least not knowledge in the sense that something you can learn from a book. It is the quality that is mentioned in an essay by pg: <a href="http://www.paulgraham.com/wisdom.html" rel="nofollow">http://www.paulgraham.com/wisdom.html</a><p>I would not call this problem ignorance. Even though stupidity is kinda harsh, it captures the feeling well.