"Everything you do, if not in a relaxed state will be done at a lesser level than you are proficient. Thus the tensed expert marksman will aim at a level less than his/her student."

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For myself, I am interested in science and in philosophy only because I want to learn something about the riddle of the world in which we live, and the riddle of man's knowledge of that world. And I believe that only a revival of interest in these riddles can save the sciences and philosophy from an obscurantist faith in the expert's special skill and in his personal knowledge and authority.

— Karl Popper