Leibniz and the Ground of Possibility

Abstract

Leibniz’s views on modality are among the most discussed by his interpreters. Although most of the discussion has focused on Leibniz’s analyses of modality, this essay explores Leibniz’s grounding of modality. Leibniz holds that possibilities and possibilia are grounded in the intellect of God. Although other early moderns agreed that modal truths are in some way dependent on God, there were sharp disagreements surrounding two distinct questions: (1) On what in God do modal truths and modal truth-makers depend? (2) What is the manner(s) of dependence by which modal truths and modal truth-makers depend on God? Very roughly, Leibniz’s own answers are: (1) God’s intellect and (2) a form of ontological dependence. The essay first distinguishes Leibniz’s account from two nearby (and often misunderstood) alternatives found in Descartes and Spinoza. It then examines Leibniz’s theory in detail, showing how, on his account, God’s ideas provide both truth-makers for possibilities and necessities and an ontological foothold for those truth-makers, thereby explaining modal truths. Along the way, it suggests several refinements and possible amendments to Leibniz’s grounding thesis. It then defends Leibniz against a pair of recent objections by Robert Merrihew Adams and Andrew Chignell that invoke the early work of Kant. I conclude that whereas Leibniz’s alternative avoids collapsing into yet another form of Spinozism, the alternatives proposed by Adams, Chignell, and the early Kant do not.

Backing into Spinozism

“…For passages that sound closer to Leibniz's intellectualist position, see LO 618 and JS 128 and 197. (It is easy, but probably incorrect, to conflate Malebranche's appeals to God's wisdom and God's intellect, as I fear I did in Newlands (2013).) 42 Kant's reasons for favoring actual exemplification over mere thinking are more complex than I can get into here; for further discussion, see Adams (2000) and Chignell (2009). 12 0 .…”

“…The basic idea seems to be that possibilities are explained through their grounds, and so ungrounded possibilities would be unexplained. 38 This way of framing the disputes is from Newlands (2013). 39 Although I disagree with his objections to Leibniz on behalf of Kant, Andrew Chignell has cogently presented a version of the concern I am raising here about the path from Kant's early theory of modality to Spinozism (Chignell (2012)).…”

“…For passages that sound closer to Leibniz's intellectualist position, see LO 618 and JS 128 and 197. (It is easy, but probably incorrect, to conflate Malebranche's appeals to God's wisdom and God's intellect , as I fear I did in Newlands (). )…”

“…For Leibniz-friendly reasons and texts to resist this reductionist line, see Newlands (2013). 34 See, for example, NE 131-133.…”

“…See, for example, the opening chapters of Nachtomy (2007). 36 For the does, see CP 43, Ak 6.4.1389, and 6.4.2317; for the should, see Newlands (2013). 37 Leibniz could also push back that the explanatory cost here is not any higher than others have to pay eventually.…”