that the many parts make up one human being, that many individual units make up a single ten, that many pieces of matter make up one house or even one city, and the same holds for countless other examples—so numerous they cannot be tallied and so obvious they cannot be hidden.

How, then, can you fault the Christians for saying something analogous, and on what basis do you reject the notion that three hypostases could constitute one substance?

It is replied: When we speak of “one human being,” “one house,” “one ten,” and the like, these are merely names that point to composites, not to single, indivisible entities. Saying “one human being” is, in effect, saying “one aggregate,” and the same is true when we say “one ten”; we are not claiming that it is literally one in itself. After all, we maintain that a person’s parts are distinct—each part differs from the others—and likewise each of the ten units differs from the rest. Thus, even when we declare “one human being,” we are not ascribing absolute unity to him in his very essence; were we to do so, we would fall into the very contradiction for which we censure the Christians.

What we mean, rather, is that it is a single composite whole. Had the Christians said likewise, maintaining that these are three things forming a single aggregate, they would not have contradicted themselves. When they describe the three hypostases as one substance, their words could only bear the sense we intend when we say that many parts together form one human being. In that case, calling it a substance would simply indicate a composite whole—but that is not what they mean, nor is it what they believe or allow it to signify, for they do not concede