PHIL 855.001 – Research Seminar in Philosophy of Logic

Instructor: Thomas Hofweber. This course meets T 4:00 – 6:30 p.m. in CW 213.

It is tempting to think that logic is special in various ways that other disciplines like physics and psychology are not. But in what sense logic is supposed to be special and whether it indeed is special in this way is not so clear. In this class we will look at a number of such ways and critically assess them. Among them are the following: Is logic in some sense normative that other disciplines are not? For example, is logic normative for thought in general, such that there is an intimate connection between logic and proper thinking? Is it ever possible to rationally revise ones own logic? Can one ever have good enough reasons to think that one has the wrong logic, or is logic somehow immune to revision? Can one make sense of that other thinkers might be governed by a completely different logic than oneself? Are logical truths somehow knowable a priori? Are logical truth shallow and merely analytic or true by convention, or are they deep, and reveal the basic metaphysical structure of the world? And does that distinction in the last question make sense? Are the precise formal languages used in formal logic an improvement over natural languages, and should proper theorizing thus be carried out in such formal languages? In particular, should metaphysics be conducted using formal languages that are supposed to be an improvement over natural languages, for example since they contain expressive resources lacking in natural languages? Can we make sense of an artificial language that is expressively richer than our natural languages? Or are formal languages best seen as models of features of natural languages, and natural languages thus have priority in metaphysical theorizing? Can the laws of logic tolerate exceptions, or are they refuted by a single instance where they don’t hold? Do the paradoxes show that classical logic is mistaken, and thus should be revised? What is the rational reaction to paradoxes like Curry’s Paradox? And so on and so forth.

We will be reading and discussing recent articles on these topics. Although many of these questions have been discussed throughout the history of philosophy, our focus will not be historical. Nonetheless, the views of Kant, Frege and Carnap will make repeated appearances.

There are no real prerequisites for this class. Although it is about logic, very little serious logic is actually presupposed. Most of the discussion will be about modus ponens and the like, with the exception being the discussion of “higher-order metaphysics” towards the end, when we will discuss the proposal to conduct metaphysics using higher-order languages, but the technical background there will be explained. It is more important to have a general background in epistemology, metaphysics, and the philosophy of language.

PHIL graduate students: Please refer to our Handbook (page 6, #9) for information regarding distribution requirements.

Permission of the instructor is required to enroll in this course. PHIL grad students are exempt from this enrollment requirement.