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. This is not ignorance…
you can argue all you like that the author should use another word. but what you have to get over when you're doing research is exactly that feeling. the feeling that people are trying to hide from by playing with words.
not sure i am making my point well - what i am trying to say is that the people who are complaining about the term "stupid" are not helping anyone. they're just exhibiting the same instinctive reaction that you feel in research. whatever name you give it, you feel the same.