[Robert Bolt and Michael Wilson, who wrote the screenplay for Lawrence of Arabia, may have read Schopenhauer. Schopenhauer wrote, ‘A man can do what he wants, but not want what he wants.’ In the youtube clip below Lawrence, after being tortured by the Turks, tells Ali that he has to abandon the Arab revolt. Ali remonstrates with him, saying, “a man can do whatever he wants. . . you said.” Lawrence replies, “He can, but he can’t want what he wants.” The meaning of this paradoxical remark is indicated clearly enough by the immediate context, and more fully by Lawrence’s whole career as described in the film. Perhaps Schopenhauer’s statement could be expanded as follows: A man can do what his reason and conscience tell him is right and good, but he cannot desire what his reason and conscience tell him is right and good. In Lawrence’s case, however, it may be more a matter of desire being weakened by physical and emotional exhaustion.]

http://www.youtube.com/watch?v=jZHKujjul-I&feature=related