The paper examines three essays that Leibniz wrote in 1688, immediately after the composition of the Discourse on Metaphysics, one of his most organic philosophical works. The main topics which emerge from these essays are: the relationship between substance and accidents; the nature of accidents; and, more generally, the nature of abstract entities. Given that accidents' nature is that of changing, Leibniz sees how hard it is to give an account of the relationship between substance and accidents that does not (...) imply any change in the substance, when its accidents undergo a change. To find a way out of this problem, Leibniz assumes that abstract terms (whiteness, wisdom, etc.) do not name real properties or real parts of substances, and that any sentence containing real abstract terms can be rephrased as a sentence containing logical abstract terms, which do no imply any commitment to the existence of real properties. Coherently with this nominalistic attitude, Leibniz ends up, in the Theodicy and in his correspondence with Des Bosses, considering accidents as modes or internal modifications of the substance. (shrink)

Imaguire-Guido_On-the-ontology-of-relations.

Leibniz thinks that every created substance is causally active, and yet causally independent of every other: none can cause changes in any but itself. This is not controversial. But Leibniz also thinks that every created substance is existentially independent of every other: it is metaphysically possible for any to exist with or without any other. This is controversial. I argue that, given a mainstream reading of Leibniz’s essentialism, if one accepts the former, uncontroversial interpretation concerning causal independence, then one ought (...) also to accept the latter, controversial one concerning existential independence. This is a new way to defend the ‘existential independence’ interpretation. Moreover, this defense provides a new approach for defending the broadly ‘non-logical’ interpretive camp in the longstanding debate over Leibniz’s views on incompossibility, against perhaps the strongest objection leveled by advocates of the opposing broadly ‘logical’ interpretation. (shrink)

Leibniz accepts causal independence, the claim that no created substance can causally interact with any other. And Leibniz needs causal independence to be true, since his well-known pre-established harmony is premised upon it. So, what is Leibniz’s argument for causal independence? Sometimes he claims that causal interaction between substances is superfluous. Sometimes he claims that it would require the transfer of accidents, and that this is impossible. But when Leibniz finds himself under sustained pressure to defend causal independence, those are (...) not the reasons that he marshals in its defense. Instead, deep into his long correspondence with Burchard de Volder, he gives a different sort of argument, one that has gone nearly unnoticed by commentators and has not yet been properly understood. In part, this is because the argument develops slowly over four years of correspondence. It emerges in early 1704, but it is formulated tersely and appears murky unless understood in light of Leibniz and De Volder’s tangled exchanges. There Leibniz argues that, on his distinctive ontology of an infinity of created substances, no two created substances could possibly causally interact, for roughly the same reasons that some Cartesians like De Volder deny interaction between minds and bodies on their substance dualist ontology. In this paper I draw out this lost argument, explain it and the metaphysics on which Leibniz builds it, and untangle Leibniz and De Volder’s exchanges concerning causation from which this argument results. (shrink)