You have here an unusual opportunity to appraise the human mind, or to
examine, in Earth terms, the roles of good and evil in a man. His
negative side, which you call hostility, lust, violence; and his
positive side, which Earth people express as compassion, love,
tenderness. And what is it that makes one man an exceptional leader?
We see here indications that it is his negative side which makes him
strong -- that his evil side, if you will, properly controlled and
disciplined, is vital to his strength.Your negative side, removed
from you, the power of command begins to elude you.
-- Spock, "The Enemy Within," stardate 1673.1
