conclusion. But no simple and primary statement is termed a syllogism, although true; but it is compounded of three such, at the least,—of two as premisses, and one as conclusion.
Now, either all things require demonstration, or some of them are self-evident. But if the first, by demanding the demonstration of each demonstration we shall go on ad infinitum; and so demonstration is subverted. But if the second, those things which are self-evident will become the starting points [and fundamental grounds] of demonstration.
In point of fact, the philosophers admit that the first principles of all things are indemonstrable. So that if there is demonstration at all, there is an absolute necessity that there be something that is self-evident, which is called primary and indemonstrable.
Consequently all demonstration is traced up to indemonstrable faith.
It will also turn out that there are other starting points for demonstrations, after the source which takes its rise in faith,—the things which appear clearly to sensation and understanding. For the phenomena of sensation are simple, and incapable of being decompounded; but those of understanding are simple, rational, and primary. But those produced from them are compound, but no less clear and reliable, and having more to do with the reasoning faculty than the first. For therefore the peculiar native power of reason, which we all have by nature, deals with agreement and disagreement. If, then, any argument be found to be of such a kind, as from points already believed to be capable of producing belief in what is not yet believed, we shall aver that this is the very essence of demonstration.
Now it is affirmed that the nature of demonstration, as that of belief, is twofold: that which produces in the souls of the hearers persuasion merely, and that which produces knowledge.
If, then, one begins with the things which are evident to sensation and understanding, and then draw the proper conclusion, he truly demonstrates. But if [he begin] with things which are only probable and not primary, that is evident
