 The most obvious problem with this view of the proposition [De Morgan’s way of handling relational arguments] is that it does not seem general enough. If we can unite two terms into a proposition by relating them, why not three or four or ten terms? De Morgan’s concern with the relational syllogism seems to have precluded this generalization; but there is no reason in principle why it could not be made. For this, though, we must wait for Frege and Peirce. (Merrill 1990: 110)