In contrast the solution of the other antinomies is that both thesis and antithesis are true, and that is possible because they are concerned with different things. The third antinomy arises from the difficulty of applying the category of causation to the world as a whole. The assumption underlying the thesis is not, as is sometimes asserted, merely that the notion of infinity in itself implies a contradiction, but that a determinate result must have a determinate cause. If we think of what actually exists now as having been caused by what has preceded it, we must think of that which has had a determinate result being itself determinate. It is the familiar argument for a first cause. In causation we seem to be relating one event to another event, and are really only putting the question of origination further back. Yet, if we say that therefore we must suppose an absolute origination of change, a beginning of the series, we have to answer the question, How is it possible to think of the originating number of the series? For to think that something can arise from nothing is to contradict the principle of causation. Kant’s solution to this difficulty is important, for it had great influence upon his ethical theory. The category of causation applies only to phenomena. If we think of things as phenomena we must recognise that they are subject to the principle of causation; if we think of them as things in themselves, the category of causation does not apply to them, and their action may be free. The same action may therefore on its phenomenal side be determined, and on its nominal side, as the action of a thing in itself, be free. This may seem to be solving one contradiction by propounding another, till we remember that in causation we do not explain the relation of cause to effect. The relation we discover is between one instance of cause and effect and another. Like causes have like effects. The principle applies, then, in so far as things are like one another. It applies to changes which are aggregates or complexes of simpler changes which are like other changes. If and in so far as there are things which are more than aggregates of their elements, and are therefore unique, there are things to whose changes no laws of cause and effect are adequate. The point may be illustrated by the way we think about character. If we think of a man’s character as his characteristics, his being this or that _kind_ of person, we must think of his action as so far determined, but that does not prevent us from thinking of his individuality as something more than any sum or combination of characteristics, as something essentially alive, which escapes all attempts to bind it by rules. It is the difference in Kant’s words between man regarded "from the point of view of anthropology," and man regarded as a responsible moral being. We shall see in the next chapter that this distinction is the basis of Kant’s moral theory.