First something will be said about ends. There are three things which follow in order and are called first end, middle end and last end. They are also called end, cause and effect. Those three must be together in everything in order that they may be anything. For a first end without a middle end and, at the same time, a last end, is not possible. Or what is the same, there cannot be end alone without cause and effect. Similarly, there cannot be cause alone without the end from which, and without the effect in which, it is; or an effect alone, that is, an effect without its cause and end. That this is so maybe comprehended if it be thought that an end without an effect, that is, separated from an affect, is not an existing thing, and so is nothing but a word. For in order that an end may actually be an end, it must be terminated, and it is terminated in an effect in which it is first called end because it is an end. It appears as if the agent or formative principle exists by itself, but this is an appearance from its being in the effect, but if it is separated from the effect, it is instantly sundered. From the foregoing it is clear that those three, end, cause and effect must be in every thing to make it anything.