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• The supreme triumph of reason is to cast doubt upon its own validity: -- Miguel de Unamuno
• Those who believe that they believe in God, but without passion in their hea
  without anguish in mind, without uncertainty, without doubt, without an element of despair even in their consolation, believe only in the God idea, not God Himself....
• If a person never contradicts himself, it must be that he says nothing. Miguel de Unamuno
• To fall into a habit is to begin to cease to be.
  -- Miguel de Unamuno, "The Tragic Sense of Life", 1913...
• Love is the child of illusion and the parent of disillusion. -- Miguel de Unamuno
• Nadie tiene mas imaginacion que la realidad. -- Miguel de Unamuno, "El Espejo de la Muerte", 1941
• Doubt isn't the opposite of faith; it is an element of faith. -- Paul Tillich, German theologian.
• You call for faith: I show you doubt, to prove that faith exists.
  The more of doubt, the stronger faith, I say, If faith overcomes doubt....