But there's the rub. The present can never deliver one thing: meaning. The way of happiness and meaning are not the same. To find happiness, a man need only live in the moment; he need only live for the moment. But if he wants meaning--the meaning of his dreams, his secrets, his life--a man must reinhabit his past, however dark, and live for the future, however uncertain. Thus nature dangles happiness and meaning before us all, insisting only that we choose between them.