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Instructor: Rosalind Chaplin. This course meets W 4:00 – 6:30 p.m. in CW 213.

Roughly speaking, the Principle of Sufficient Reason (PSR) says that every thing, fact, or state of affairs has an explanation that accounts for why it is the way it is. Traditionally understood, this principle demands thoroughgoing intelligibility for everything: if the PSR is true, then there are no brute facts, and everything can be explained. In the European philosophical tradition of the 17th and 18th centuries, many of the most important metaphysical and epistemological debates centered on questions about the status of the PSR and the upshots of a commitment to it. In this seminar, we will examine these debates and the place of the PSR in broadly rationalist metaphysical systems. We will focus on the following questions:
1. How exactly should we understand the demand for intelligibility made in the PSR?
2. Can the PSR be proved?
3. If the PSR is true, what follows from it? Necessitarianism? Idealism? Monism?
4. Does the PSR lead to paradoxes without a restriction of its scope? How might one argue for principled restrictions of its scope?
The majority of the course (about 70%) will focus on historical figures, but we will also examine the recent revival of interest in the PSR in contemporary metaphysics (about 30% of the course). Our historical star players will be Spinoza, Leibniz, and Kant, but we will also read selections from lesser known figures whose influence on debates about the PSR was significant: Christian Wolff, Émilie du Châtelet, Alexander Baumgarten, and Christian August Crusius.


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.