We have seen how Heidegger has interpreted each of the modes of the threefold synthesis as modes of time. Apprehension is essentially oriented to the present, reproduction to the past, and precognition to the future. However, Heidegger has left unclear the extent to which he concurs with Kant's belief that the third mode of synthesis is central. Kant had said that the pure form of the third mode of synthesis is apperception, which is the ground of the unity of synthesis in general. However, Heidegger demurs at equating the pure aspect of the third mode of synthesis with apperception, and instead insists that this a priori mode was precognition, that is, a pure projection of nature as a whole. Heidegger does however recognize that this third mode has a leading role among the three modes of synthesis, and indeed has a special relationship to apperception. It is this connection that we will examine now.