Without ambition one starts nothing. Without work one finishes nothing. The prize will not be sent to you. You have to win it. The man who knows how will always have a job. The man who also knows why will always be his boss. As to methods there may be a million and then some, but principles are few. The man who grasps principles can successfully select his own methods. The man who tries methods, ignoring principles, is sure to have trouble.
Ralph Waldo Emerson (hat tip to Jabe Bloom)