They are.
And if to the two a third be added in due order, the number of terms will be three, and the contacts two?
Yes.
And every additional term makes one additional contact, whence it follows that the contacts are one less in number than the terms; the first two terms exceeded the number of contacts by one, and the whole number of terms exceeds the whole number of contacts by one in like manner; and for every one which is afterwards added to the number of terms, one contact is added to the contacts.
True.
Whatever is the whole number of things, the contacts will be always one less.
True.
But if there be only one, and not two, there will be no contact?
How can there be?
And do we not say that the others being other than the one are not one and have no part in the one?