It is clear from our last selection that Peirce is already on the verge of a graphical syntax for the logic of relative terms. Indeed, it is likely that he had already reached this point in his own thinking some time before.

For instance, it seems quite impossible for a person with any graphical sensibility whatever to read that last variation on “a giver of a horse to a lover of a woman” without drawing or at least imagining lines of identity to connect the corresponding marks of reference, as shown in the following Figure.

(3)