Billy had a framed prayer on his office wall which expressed his method for keeping going, even though he was… — Kurt Vonnegut

Billy had a framed prayer on his office wall which expressed his method for keeping going, even though he was unenthusiastic about living. A lot of patients who saw the prayer on Billy's wall told him that it helped them to keep going, too. It went like this: "God grant me the serenity to accept the things I cannot change, courage to change the things I can, and wisdom always to tell the difference."

Among the things Billy Pilgrim could not change were the past, the present, and the future. (p. 60)

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