presuppose the former series, to be able to consider n as given, and n is according to reason (the totality of conditions) possible only by means of that series. But its possibility does not rest on the following series o, p, q, r, which for this reason cannot be regarded as given, but only as capable of being given (dabilis).
I shall term the synthesis of the series on the side of the conditions —from that nearest to the given phenomenon up to the more remote —regressive; that which proceeds on the side of the conditioned, from the immediate consequence to the more remote, I shall call the progressive synthesis. The former proceeds in antecedentia, the latter in consequentia. The cosmological ideas are therefore occupied with the totality of the regressive synthesis, and proceed in antecedentia, not in consequentia. When the latter takes place, it is an arbitrary and not a necessary problem of pure reason; for we require, for the complete understanding of what is given in a phenomenon, not the consequences which succeed, but the grounds or principles which precede.
In order to construct the table of ideas in correspondence with the table of categories, we take first the two primitive quanta of all our intuitions, time and space. Time is in itself a series (and the formal condition of all series), and hence, in relation to a given present, we must distinguish a priori in it the antecedentia as conditions (time past) from the consequentia (time future). Consequently, the transcendental idea of the absolute totality of the series of the conditions of a given conditioned, relates merely to all past time. According to the idea of reason, the whole past time, as the condition of the given moment, is necessarily cogitated as given. But, as regards space, there exists in it no distinction between progressus and regressus; for it is an aggregate and not a series—its parts existing together at the same time. I can consider a given point of time in relation to past time only as conditioned, because this given moment comes into existence only through the past time rather through the passing of the preceding time. But as the parts of space are not subordinated, but co-ordinated to each other, one part cannot be the condition of the possibility of the other; and space is not in itself, like time, a series. But the synthesis of the manifold parts of space —(the syntheses whereby we apprehend space) —is nevertheless successive; it takes