The Bicentennial of the American Revolution ought to be a time for restoring the dialogue between the spirit of the past and the spirit of the future in our national life. We commemorate our origins because our origins are intertwined with our destiny; memory is the reciprocal of hope, and conservation and change are essential to each other. "There is nothing real without both . . . ," as Alfred North Whitehead once said. "Mere conservation without change cannot conserve . . . , mere change without conservation is a passage from nothing to nothing."