John's ideal Thomas.
Only one of the three Johns is taxed; only one can be weighed on a platform-balance; but the other two are just as important in the conversation.

Let us suppose the real John to be old, dull, and ill-looking.

But as the Higher Powers have not conferred on men the gift of seeing themselves in the true light, John very possibly conceives himself to be youthful, witty, and fascinating, and talks from the point of view of this ideal.

Thomas, again, believes him to be an artful rogue, we will say; therefore he is, so far as Thomas's attitude in the conversation is concerned, an artful rogue, though really simple and stupid.

The same conditions apply to the three Thomases.