To Contradict is to Cooperate: Prior, Abelard, Buridan, Grice

Suppose we’re at a horserace, and you turn to me and say, ‘Eclipse is at the finish line!’ But by the time you’ve finished saying this—by the time your utterance is complete—Eclipse is already well past the finish line, and what you’ve said is no longer true. But you did say something true. More generally, we can—and often do—say true things about events that take up less time than our utterances themselves. We can also contradict each other about such events—something that takes even more time. How is all this possible? In the twentieth century, this problem was discussed by Arthur Prior. In the 14th, John Buridan treated an older—probably 12th-century—version of it. Buridan’s treatment is more successful than Prior’s, which runs into Zeno’s paradox of the arrow. Buridan avoids the paradox, but faces further puzzles for his account of contradiction. In untangling these, we’ll uncover important latent features of his pragmatics and temporal logic—features that are supported by more recent research in linguistics. Ultimately, our considerations here will turn up new insight into the Gricean Cooperative Principle. In a slogan: to contradict is to cooperate.