Activity implies the change of something into something different. So much, I think, is clear; but activity is not a mere uncaused alteration. And in fact, as we have seen, that is really not conceivable. For Ab to become Ac, something else beside Ab is felt to be necessary; or else we are left with a flat self-contradiction. Thus the transition of activity implies always a cause.
Activity is caused change, but it also must be more. For one thing, altered by another, is not usually thought active, but, on the contrary, passive. Activity seems rather to be self-caused change. A transition that begins with, and comes out of, the thing itself is the process where we feel that it is active. The issue must, of course, be attributed to the thing as its adjective; it must be regarded, not only as belonging to the thing, but as beginning in it and coming out of it. If a thing carries out its own nature we call the thing active.
But we are aware, or may become aware, that we are here resting on metaphors. These cannot quite mean what they say, and what they intimate is still doubtful. It appears to be something of this kind: the end of the process, the result or the effect, seems part of the nature of the thing which we had at the beginning. Not only has it not been added by something outside, but it is hardly to be taken as an addition at all. So far, at least, as the end is considered as the thing’s activity, it is regarded as the thing’s character from the first to the last. Thus it somehow was before it happened. It did not exist, and yet, for all that, in a manner it was there, and so it became. We should like to say that the nature of the thing, which was ideal, realized itself, and that this process is what we mean by activity. And the idea need not be an idea in the mind of the thing; for the thing, perhaps, has no mind, and so cannot have that which would amount to volition. On the other hand, the idea in the thing is not a
