Page:Theory of Mind of Roger Bacon.djvu/31

 proper qualities and to substances. And, it should be added, not only are they able to do so, but they are doing so continually.

With this then we have given the limitation of the production of the Species. It is produced by all things save Matter and its properties; and its activity is confined to the production of qualitative change as opposed to change in size or change in position. But the question as to what things are adapted to complete their Species, when once produced, requires a few words.

It is to be observed that this question does not strictly concern the Species as such; for Bacon means the Species to be essentially incomplete. It is a question affecting rather the completion of the Effect. But because this conception of complete as opposed to incomplete was one with which Bacon was inclined to play fast and loose, it is especially desirable that we should have his meaning clear. In its phase as applied to the Species we have already presented it; we shall here view it in its phase as touching the Effect.

In his effort to present the conception of the Species which he has in mind, the example which he most frequently employs is that of an Agent which is actually able to complete its effect. And the term Species derives its whole meaning from the fact that there is a stage where the effect is an incomplete one. In the cases, then, where there is no stage at which it becomes complete, by reference to what does the Species acquire meaning? By reference to the Agent with which it is identical in essence; and in which case it is an incomplete reproduction of the Agent. And hence it is that we find him speaking in some cases of the effects, and in other cases of the Species, as being completed. Let us therefore see in what cases the Species, or effect, remains incomplete.

We have his own summary reply to this question. The “nobler” Agents, he says, do not complete their Species, such for example as angels, the Heavens, men and other animate objects; nor do inanimate objects, in so far as they are compounded from the elements. Because everything would then generate a complete individual exactly like itself, which would result in the elimination of the various orders of being as we find them. Moreover, there are certain Agents, such as color, odor, taste, and sound, which are of a kind too “weak” to complete the Species which they produce. In fact, only light and the four touch-qualities (heat and cold,