22. One very important point concerning the idea of being remains to be illustrated, and that is, whether this idea has possible or real being for its object. The scholastics taught that the object of the understanding was being; nor were they altogether without reason in so doing, since one of the things we conceive of with the greatest distinctness, and which is found to be the most fundamental in all our ideas, is the idea of being, containing as it does in a certain manner all other ideas. But as being is distinguished into actual and possible, a difficulty occurs as to which of these categories the idea of being, the chief object of our understanding, is applicable to. 23. The Abbate Rosmini, in his _Nuovo Saggio sull' origine delle idee_, pretends that the form and the light of our understanding, and the origin of all our ideas, consists in the idea, not of real, but of possible being. "The simple idea of being," he says, "is not the perception of any existing thing, but the intuition of some possible thing; it is no more than the idea of the possibility of the thing."[20] [20] Sec. 5, P. 1, C. 3, A. 1, § 2. I very much doubt the truth of this; and there seems also to be some confusion of ideas here. He ought to have defined possibility itself for us, before making the idea of it enter into that of being. I will myself give a definition of it, and this may serve greatly to facilitate the understanding of the whole matter. 24. What is possibility? The idea of possibility, abstracted from its classifications, offers us a general idea of the non-repugnance, or non-exclusion, of two things with respect to each other; just as the idea of impossibility presents us such a repugnance or exclusion. A triangle cannot be a circle. A triangle may be equilateral. In the former case we affirm the repugnance of the ideas of the triangle and of the circle: in the latter, the non-repugnance of a triangle having its three sides equal. It may be said that in these cases there is no question of the existence of the triangle or of the circle; and that the possibility or impossibility is referred to the repugnance of their essences, abstracted from their existence or non-existence, although ideal impossibility draws along with it real impossibility. 25. Since, whenever impossibility is asserted, repugnance also, is asserted, and there can be no repugnance of a thing with itself, it follows that impossibility is only possible when two or more ideas are compared. On the other hand, when there is no repugnance there is possibility; then, no simple idea, of itself alone, can offer to us an impossible object. The object, therefore, of every simple idea is always possible, that is, is not repugnant.