Thomas Jefferson, letter to John Page (July 15, 1763); in Julian P. Boyd, ed., The Papers of Thomas Jefferson (1950), vol. 1, p. 10. Jefferson used the spelling "beleive". This letter was written in hopes that John Page would talk to Belinda, a young woman with whom Jefferson, then 20, was infatuated. Jefferson was normally cool and level-headed, but Belinda had a devastating effect on his poise, leaving him tongue-tied and stammering. Saul K. Padover, Jefferson (1942), chapter 2, p. 20.https://en.wikiquote.org/wiki/Happiness