A Path to the Tractatus: From Facts and Forms Through Picturing to Modality

This chapter traces Wittgenstein’s philosophical development culminating in the conception, central to Tractatus Logico-Philosophicus, of propositions as involving essentially a primitive notion of possibility. I spell out three stages of this philosophical development, starting from criticism of Russell’s multiple-relation theory of judgment, going through the conception of propositions as signifying facts in “Notes on Logic,” to struggles with what Wittgenstein calls the “Wahrheitsprobleme” in his wartime notebooks, in which he first considers appealing to the idea of picturing to understand propositions, before finally arriving at the modal view of proposition in the Tractatus. I also sketch the broader philosophical significance of the Tractarian conception of propositions, namely, Frege and Russell’s rejection of modality, and so of a venerable tradition of characterizing logic in modal terms. Against this background, Wittgenstein’s view of propositions in the Tractatus is part of a rejoinder to Frege and Russell, bringing modality back into logic.