The years of adolescence were to me very lonely and very unhappy. Both in the life of the emotions and in the life of the intellect, I was obliged to preserve an impenetrable secrecy towards my people. My interests were divided between sex, religion, and mathematics. I find the recollection of my sexual preoccupation in adolescence unpleasant. I do not like to remember how I felt in those years, but I will do my best to relate things as they were and not as I could wish them to have been.
Source:The Autobiography of Bertrand Russell, v.1, chap. 1, 1967
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