If the Greeks had possessed the microscope, they would in all probability never have been thrown into debate over the famous question of their philosophy, whether the relation of the soul to the body is that of harmony to a harp, or of a rower to a boat. According to the former of these two theories, the music must cease when the harp is broken : according to the latter, the rower may survive, although his boat is destroyed. He may be completely safe, even when his frail vessel, splintered by all the surges and lightnings, rots on the tusks of the reefs, or sinks in the fathomless waste, or dissolves to be blown about the world by the howling seas. In the one case, death does, in the other it does not, end all. Dim as was to the Greeks of Pericles' day the whole field which science has entered with the microscope for the first time in the last fifty years, all their greatest poets and philosophers held that the relation of the soul to the body is that of the rower to a boat.