Always, whenever I reach some certainty, my repose and assurance are short-lived. New doubts and anxieties quickly spring from this certainty, and I am obliged to inaugurate a hew struggle to deliver myself from the former certitude and find a new one—until finally that new one matures in its turn and is transformed into uncertainty. . . . How, then, can we define uncertainty? Uncertainty is the mother of a new certainty.
