Now, suppose that there are two species of order, and that these two orders are two contraries within one and the same genus. Suppose also that the idea of disorder arises in our mind whenever, seeking one of the two kinds of order, we find the other. The idea of disorder would then have a clear meaning in the current practice of life: it would objectify, for the convenience of language, the disappointment of a mind that finds before it an order different from what it wants, an order with which it is not concerned at the moment, and which, in this sense, does not exist for it. But the idea would not admit a theoretical use. So if we claim, notwithstanding, to introduce it into philosophy, we shall inevitably lose sight of its true meaning. It denotes the absence of a certain order, but _to the profit of another_ (with which we are not concerned); only, as it applies to each of the two in turn, and as it even goes and comes continually between the two, we take it on the way, or rather on the wing, like a shuttlecock between two battledores, and treat it as if it represented, not the absence of the one or other order as the case may be, but the absence of both together--a thing that is neither perceived nor conceived, a simple verbal entity. So there arises the problem how order is imposed on disorder, form on matter. In analyzing the idea of disorder thus subtilized, we shall see that it represents nothing at all, and at the same time the problems that have been raised around it will vanish. It is true that we must begin by distinguishing, and even by opposing one to the other, two kinds of order which we generally confuse. As this confusion has created the principal difficulties of the problem of knowledge, it will not be useless to dwell once more on the marks by which the two orders are distinguished.