"Anyone who has ever made a resolution discovers that the strength of that determination fades in time. The moment you feel that is when you should make a fresh determination. Tell yourself, “OK! I will start again from now!†If you fall down seven times, get up an eighth. Don’t give up when you feel discouraged-jus t pick yourself up and renew your determination each time."
Source : "Reason for Changing his Democratic Opinions" as quoted in "Hoyt's New Cyclopedia Of Practical Quotations" by Jehiel Keeler Hoyt, (p. 93), 1922.