advantageous, or that it is neither beautiful nor advantageous. Still if we cannot prove both, we must prove one, of them, showing that the one is, but the other not; but the reasoning is the same, though there should be more members in the division.
Again, (we must consider) those things which are not equivocally predicated in many ways, but in some other way, thus science is one of many, either as belonging to the end, or to that which pertains to the end, as medicine (is the science) of producing health, and of prescribing diet, or as belonging to both ends, as of contraries there is said to be the same science, (since the one) is no more an end than the other, or as belonging to that which is per se, and to that which is accidental, as (we know) per se that a triangle has angles equal to two right, but according to accident, that it is equilateral, for because it happens to an equilateral triangle to be a triangle, according to this we know that it has angles equal to two right. If then it is by no means possible that there should be the same science of many things, it is clearly altogether impossible, or if in a certain respect it is possible, it is clear that it is possible. Nevertheless, we must distinguish in how many ways it is useful; for instance, if we desire to confirm we must introduce such things as are possible, and we must divide them into those only which are useful to confirmation; but if we would subvert, (we must introduce) such things as are impossible, and omit the rest. This too must be done in these, when it is latent in how many ways they are predicated, that this also belongs to that, or does not belong, must be confirmed from the same places; as that this science is of this thing, either as belonging to the end, or to those things which pertain to the end, or as to those which are accidental, or on the other hand, that a thing is not according to any of the above-mentioned modes. The same reasoning also subsists about desire and such other things as are said to belong to many, for desire belongs to this thing either as to the end, as to health, or as to those things which pertain to the end, as to the taking medicine, or as to that which is from accident, as in wine, he who loves sweetness (desires wine), not because it is wine, but because it is sweet, since he desires sweetness per se, but
