Why—i.e., with what legitimacy [354] and necessity—is this principle required for the being of nature such as it confronts us?
As we derive this principle of persistence in connection with the necessity of an inter-subjective time-determination, a new and essential feature of time emerges: time is persistence. As Kant says, “Persistence gives general expression to time as the constant correlate of all existence of appearances, all change and all accompaniment” (B 300).112 Persistence is the condition of the possibility of one-after-another and of at-the-same-time. If the time-relation is determined as at-the-same-time, then time is understood as a sum-total. When taken in the relation of one-after-another, time is understood as a series. If I determine time (the time-relation) primarily as duration, then time is understood as a magnitude. Magnitude, series, and sum-total are the essential viewpoints within which time necessarily must be able to be placed in every time-determination as a time-reckoning. And from this necessity, in turn, the three analogies are then derived, corresponding to the viewpoints of magnitude, of series, and of sum-total, respectively.
I have already explained that in this derivation of the analogies nothing is said directly about the connection of time with the “I think.” Nonetheless, we can see here a trait in common between time and the “I think.” Even though it cannot be perceived, time as the persistent is, as such, the underlying—i.e., it is the subjectum in the strict sense in which Kant himself uses the concept subjectum, ὑποκείμενον. But Kant has also already characterized the “I think”—which can be constantly identified as the self-same—as subjectum in this sense. The I is the subjectum not so much in the sense of the “subjectivity” of the I in the sense of an ego. Rather, it is the subjectum in the sense of “the underlying” that has no predicate.
Accordingly, time is the subject’s “persistent” self-affection; it is that which originally and constantly affects; and it is that to which every [355] time-determination as a synthesis of the “I think” must come back, but to which it cannot come back [fully], so that the subject, as necessary and persistent, determines the substance of nature itself—in fact antecedently—with regard to time and in relation to apperception. This a priori determination is a principle. Given the constant self-identity of the I itself, the relation to the time-determining “I think” must be a constant relation in the sense that it constantly comes back to the same subjectum. This particular connection between the persistence of time and the necessity of a rule for determining time is something that Kant makes a remarkable use
112. [The Guyer and Wood footnote to this passage comments that “accompaniment” (Begleitung) connotes “the accompaniment of one state of affairs by another, i.e., what Kant is here otherwise calling ‘simultaneity’ or coexistence” (CPR, p. 300).]