Page:Theory of Mind of Roger Bacon.djvu/42

 the process goes on in the Patient as before. That the Sun has not through its Species produced in the medium so striking an effect as it will produce in the Earth, is due only to the fact that the medium was not so adapted to receive and develop these Species. Indeed, if it is a Star instead of the Earth, the effect will be yet more striking; it will be a complete and full effect, and without the deletion of the specific nature of the Star.

This then is conceivably the manner in which the Species in the second sense, as we have found it, might be educed even from the Matter of the Patient. Would it then seem odd that Bacon does not more fully state it in this form? It would not seem so if we consider that Bacon’s eduction theory covers, strictly taken, only those cases in which the Agent and the Patient are in immediate contact; this was obviously his own intention, as his pages show. And further, that in particular it was more easy to conceive of the Agent acting as a whole when in immediate contact with the Patient—and being so near therefore the more forcefully—than when so far removed as is the Sun from the Earth, for example. For such cases he was forced to fall back upon a modified emission theory.

And in saying that he still virtually held to the emission theory, it is obvious from the foregoing that his was a purged and refined emission theory. To be sure, he often falls, in his description, into the crude terms in which the emission theory was wont to be couched; and indeed the latter half of his treatise is bristling, at first sight, with terms which suggest an actual emission of the ray from the Agent. But that for Bacon these cruder connotations were absent, is plain from the fact that the background of his whole thought as touching the matter was deeply imbued with his eduction theory. And we have seen that the whole permits of a formulation which may be broadly, even if not strictly, spoken of as the eduction theory—or, better, the emission theory as modified by the eduction theory.

But is there not some plain explanation as to how the emission theory, even in this less crude form, could have rested in his mind side by side with his eduction theory? Fortunately for us, he unwittingly furnishes us with this explanation. It is at that point where he has completed his exposition of the eduction theory; and he is about to pass to the consideration of the laws of the propagation of the Species, as illustrated by the rays or Species of light. And he says: From the same point, whether taken as the minimal part of the Agent in breadth and depth, or from the first part of the