Metaphysical rationalism, the doctrine which affirms the Principle of Sufficient Reason (the PSR), is out of favor today. The best argument against it is that it appears to lead to necessitarianism, the claim that all truths are necessarily true. Whatever the intuitive appeal of the PSR, the intuitive appeal of the claim that things could have been otherwise is greater. This problem did not go unnoticed by the great metaphysical rationalists Spinoza and Leibniz. Spinoza’s response was to embrace necessitarianism. Leibniz’s (...) response was to argue that, despite appearances, rationalism does not lead to necessitarianism. This paper examines the debate between these two rationalists and concludes that Leibniz has persuasive grounds for his opinion. This has significant implications both for the plausibility of the PSR and for our understanding of modality. (shrink)

Cover Date: July 2006.Source Info: 115(3), 317-354. Language: English. Journal Announcement: 41-2. Subject: ACTION; CAUSATION; METAPHYSICS; REPRESENTATION; TELEOLOGY. Subject Person: SPINOZA, BENEDICT DE (BARUCH). Update Code: 20130315.

Locke is often thought to have introduced the topic of personal identity into philosophy when, in the second edition of theEssay,he distinguished the person from both the human being and the soul. Each of these entities differs from the others with respect to their identity conditions, and so they must be ontologically distinct. In particular, Locke claimed, a person cannot survive total memory loss, although a human being or a soul can.

: Perhaps the central problem which preoccupies Spinoza as a moral philosopher is the conflict between reason and passion. He belongs to a long tradition that sees the key to happiness and virtue as mastery and control by reason over the passions. This mastery, however, is hard won, as the passions often overwhelm its power and subvert its rule. When reason succumbs to passion, we act against our better judgment. Such action is often termed 'akratic'. Many commentators have complained that (...) the psychological principles that Spinoza appeals to in his account of akrasia are mere ad hoc modifications to his philosophical psychology. I show, on the contrary, that these principles follow from some of the most important and interesting aspects of Spinoza's philosophy of mind. (shrink)

Material from this paper appears in Chap. 7 of my book Reason and Being, but there is also stuff here that isn't in the book. In particular, it discusses the claims that, for Spinoza, conceiving implies explaining and that existence is identical to or reducible to conceivability. So, if you're interested in those issues, this paper might be worth a read.