Orison Swett Marden
This force, which is the best thing in you, your highest self, will never respond to any ordinary half-hearted call, or any milk-and-water endeavor, It can only be reached by your supremest call, your supremest effort. It will respond only to the call that is backed up by the whole of you, not part of you; you must be all there in what you are trying to do. You must bring every particle of your energy, unanswerable resolution, your best efforts, your persistent industry to your task or the best will not come out of you. You must back up your ambition by your whole nature, by unbounded enthusiasm and a determination to win which knows no failure... Only a masterly call, a masterly will, a supreme effort, intense and persistent application, can unlock the door to your inner treasure and release your highest powers.