The truth is that psychodynamically speaking this statement is correct and many connoisseurs of the subject know it and is that according to Sigmund Freud (father of psychoanalysis) This is correct, then, we are driven by an energy called libido, which is but a Energy of a sexual nature, That is, that many of our behaviors are directed by the aforementioned energy and that often, so be unconscious, we find ourselves thinking about sex and looking for that pleasure that is obtained, so in conclusion: "Nobody says but all They want sex. "
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