"You never know how much you really believe anything until its truth or
falsehood becomes a matter of life and death to you. It is easy to you
believe a rope to be strong and sound as long as you are merely using it
to cord a box. But suppose that you had to hang by that rope over a
precipice. Wouldn't you then first discover how much you really trusted
it? ... Only a real risk tests the reality of a belief."