Gonzalo Rodriguez-Pereyra

Descartes maintained substance dualism, the thesis that no substance has both mental and material properties. His main argument for this thesis, the so-called separability argument from the Sixth Meditation (AT VII: 78) has long puzzled readers. In this paper I argue that Descartes’ independence conception of substance (which Descartes presents in article 51 of the Principles) is crucial for the success of the separability argument and that Descartes used this conception of substance to defend his argument for substance dualism from an important objection.

In this article I address the Problem of Universals by answering questions about what facts a solution to the Problem of Universals should explain and how the explanation should go. I argue that a solution to the Problem of Universals explains the facts the Problem of Universals is about by giving the truthmakers (as opposed to the conceptual content and the ontological commitments) of the sentences stating those facts. I argue that the sentences stating the relevant facts are those like 'a has the property F', that is, sentences stating that a particular has a certain property. Finally I show how answering these questions in this way transforms the Problem of Universals, traditionally conceived as the One over Many, that is, the problem of explaining how different particulars can have the same properties, into the Many over One, that is, the problem of explaining how the same particular can have different properties. The Problem of Universals is the problem of the Many over One.

In the Discourse on Metaphysics Leibniz put forward his famous complete-concept definition of substance. Sometimes this definition is glossed as stating that a substance is an entity with a concept so complete that it contains all its predicates, and it is thought that it follows directly from Leibniz’s theory of truth. Now, an adequate definition of substance should not apply to accidents. But, as I shall point out, if Leibniz’s theory of truth is correct then an accident is an entity with a concept so complete that it contains all its predicates. The aim of this paper is to clarify Leibniz’s notion of substance in the Discourse with a view to explaining how that definition successfully distinguishes between substances and accidents.

According to one of Leibniz's theories of contingency a proposition is contingent if and only if it cannot be proved in a finite number of steps. It has been argued that this faces the Problem of Lucky Proof , namely that we could begin by analysing the concept ‘Peter’ by saying that ‘Peter is a denier of Christ and …’, thereby having proved the proposition ‘Peter denies Christ’ in a finite number of steps. It also faces a more general but related problem that we dub the Problem of Guaranteed Proof . We argue that Leibniz has an answer to these problems since for him one has not proved that ‘Peter denies Christ’ unless one has also proved that ‘Peter’ is a consistent concept, an impossible task since it requires the full decomposition of the infinite concept ‘Peter’. We defend this view from objections found in the literature and maintain that for Leibniz all truths about created individual beings are contingent

In this paper I discuss a passage from *Naming and Necessity* where Kripke assumes that the essential properties by means of which a definite description designates are a sufficient condition of its rigidity. I put forward two examples that show the falsity of this assumption. Then I examine the non-rigid character of definite descriptions that designate by means of properties that are sufficient conditions of identity of the objects designated by those descriptions. I conclude that the properties by means of which rigid descriptions designate must be both necessary and sufficient conditions of the identity of the designated objects.

Gardeners, poets, lovers, and philosophers are all interested in the redness of roses; but only philosophers wonder how it is that two different roses can share the same property. Are red things red because they resemble each other? Or do they resemble each other because they are red? Since the 1970s philosophers have tended to favour the latter view, and held that a satisfactory account of properties must involve the postulation of either universals or tropes. But Gonzalo Rodriguez-Pereyra revives the dormant alternative theory of resemblance nominalism, showing first that it can withstand the attacks of such eminent opponents as Goodman and Armstrong, and then that there are reasons to prefer it to its rival theories. The clarity and rigour of his arguments will challenge metaphysicians to rethink their views on properties.

I believe in metaphysical nihilism, the thesis that there could have been no concrete objects, because I believe in a version of the subtraction argument, the subtraction argument*, that proves it. But both Jonathan Lowe (2002) and Alexander Paseau (2002) express doubts about the subtraction argument*. Paseau thinks the argument is invalid, and Lowe argues that invoking concrete* objects is unnecessary. Furthermore Lowe attempts to rebut my objections (Rodriguez-Pereyra 2000) to his anti-nihilist argument (Lowe 1998). In this paper I defend the subtraction argument* from Paseau's and Lowe's criticisms as well as show that the premises of Lowe's anti-nihilist argument are still lacking support.

In this note we shall argue that Milne’s new effort does not refute Truthmaker Maximalism. According to Truthmaker Maximalism, every truth has a truthmaker. Milne has attempted to refute it using the following self-referential sentence M: This sentence has no truthmaker. Essential to his refutation is that M is like the Gödel sentence and unlike the Liar, and one way in which Milne supports this assimilation is through the claim that his proof is essentially object-level and not semantic. In Section 2, we shall argue that Milne is still begging the question against Truthmaker Maximalism. In Section 3, we shall argue that even assimilating M to the Liar does not force the truthmaker maximalist to maintain the ‘dull option’ that M does not express a proposition. There are other options open and, though they imply revising the logic in Milne’s reasoning, this is not one of the possible revisions he considers. In Section 4, we shall suggest that Milne’s proof requires an implicit appeal to semantic principles and notions. In Section 5, we shall point out that there are two important dissimilarities between M and the Gödel sentence. Section 6 is a brief summary and conclusion

This paper is a response to replies by Dan López de Sa and Mark Jago to my ‘Truthmaking, Entailment, and the Conjuction Thesis’. In that paper, my main aim was to argue against the Entailment Principle by arguing against the Conjunction Thesis, which is entailed by the Entailment Principle. In the course of so doing, although not essential for my project in that paper, I defended the Disjunction Thesis. López de Sa has objected both to my defence of the Disjunction Thesis and my case against the Conjunction Thesis. I shall show that his objections are unfounded and based on serious misunderstandings of my position, what the relevant debate is, and some fundamental notions of Truthmaker Theory. Jago argues that accepting the Disjunction Thesis and rejecting the Conjunction Thesis is hard to maintain. But I show that Jago has not shown that accepting the Disjunction Thesis while rejecting the Conjunction Thesis is impossible or even hard to maintain. Jago believes that, to accept the Disjunction Thesis while rejecting the Conjunction Thesis, one needs to reject his axiom (T3), which says that all the truthmakers for <P&P> are truthmakers for <P>. I argue that there are reasons to reject such a principle, and the version of it that says that what makes <P&P> true makes <P> true.

The subtraction argument, originally put forward by Thomas Baldwin (1996), is intended to establish Metaphysical Nihilism, the thesis that there could have been no concrete objects. Some modified versions of the argument have been proposed in order to avoid some difficulties faced by the original argument. In this paper I shall concentrate on two of those versions, the so-called subtraction argument* (presented and defended in Rodriguez-Pereyra 1997, 2000, 2002), and Efird and Stoneham’s recent version of the argument (Efird and Stoneham 2005). I shall defend the subtraction argument* from Alexander Paseau’s (2006) objection that because a crucial premise of the subtraction argument* may have no plausibility independent from Metaphysical Nihilism, the subtraction argument* is not suasive. Although Paseau focuses on the subtraction argument*, I shall point out that Efird and Stoneham could reply to Paseau’s objection in the same way. Thus there are (at least) two suasive versions of the subtraction argument that establish Metaphysical Nihilism. But are those two arguments equally good? I shall argue that the subtraction argument* is preferable to Efird and Stoneham’s argument.

This is a reply to Byeong-Uk Yi who argued that my _Resemblance Nominalism_ fails to account for sentences featuring abstract nouns like Carmine resembles vermillion more than it resembles French Blue and Scarlet is a colour. I accept his criticism of what I said in my book on Resemblance Nominalism about, but then I go on to show how can be accounted for. I reject his criticism of what I said in my book about. I also show how Resemblance Nominalism can account for other sentences featuring abstract nouns

Resemblance Nominalism is the view that denies universals and tropes and claims that what makes F-things F is their resemblances. A famous argument against Resemblance Nominalism is Russell's regress of resemblances, according to which the resemblance nominalist falls into a vicious infinite regress. Aristocratic Resemblance Nominalism, as opposed to Egalitarian Resemblance Nominalism, is the version of Resemblance Nominalism that claims that what makes F-things F is that they resemble the F-paradigms. In this paper I attempt to show that a recently advocated strategy to stop Russell's regress by using paradigms does not succeed.

Gonzalo Rodriguez-Pereyra presents an original study of the place and role of the Identity of Indiscernibles in Leibniz's philosophy. The Principle of the Identity of Indiscernibles rules out numerically distinct but perfectly similar things; Leibniz derived it from more basic principles and used it to establish important philosophical theses. Rodriguez-Pereyra aims to establish what Leibniz meant by the Principle of Identity of Indiscernibles, what his arguments for and from it were, and to assess those arguments and Leibniz's claims about the Principle of Identity of Indiscernibles. He argues that Leibniz had a very strong version of the principle, according to which no possibilia are intrinsically perfectly similar, where this excludes things that differ in magnitude alone. The book discusses Leibniz's arguments for the Identity of Indiscernibles in the Meditation on the Principle of the Individual, the Discourse on Metaphysics, Notationes Generales, Primary Truths, the letter to Casati of 1689, the correspondence with Clarke, as well as the use of the Identity of Indiscernibles in Leibniz's arguments against the Cartesian conception of the material world, atoms, absolute space and time, the Lockean conception of the mind as a tabula rasa, and freedom of indifference. Rodriguez-Pereyra argues that the Identity of Indiscernibles was a central but inessential principle of Leibniz's philosophy.

Universals have traditionally thought to obey the identity of indiscernibles, that is, it has traditionally been thought that there can be no perfectly similar universals. But at least in the conception of universals as immanent, there is nothing that rules out there being indiscernible universals. In this paper, I shall argue that there is useful work indiscernible universals can do, and so there might be reason to postulate indiscernible universals. In particular, I shall argue that postulating indiscernible universals can allow a theory of universals to identify particulars with bundles of universals, and that postulating indiscernible universals can allow a theory of universals to develop an account of the resemblance of quantitative universals that avoids the objections that Armstrong’s account faces. Finally, I shall respond to some objections and I shall undermine the criterion of distinction between particulars and universals that says that the distinction between particulars and universals lies in that while there can be indiscernible particulars, there cannot be indiscernible universals.

What I call the argument from almost indiscernibles is an argument, put forward by Robert Adams in 1979, for the possibility of indiscernibles based on the possibility of almost indiscernibles. The argument is that if almost indiscernibles are possible, indiscernibles are possible, but since almost indiscernible are possible, indiscernibles are possible. The argument seems to be an improvement over the mere appeal to intuitions, like that suggested by Max Black, that situations in which there are indiscernibles are possible, for the argument purports to give us a reason that indiscernibles are possible. In this paper I shall assess the argument by examining whether there is support for the conditional premise that if almost indiscernibles are possible, indiscernibles are possible. I shall argue that there are reasons to think that either the premise lacks support or almost indiscernibles are dispensable. If the premise lacks support, the argument does not establish the possibility of almost indiscernibles; if almost indiscernibles are dispensable, the argument is not needed to establish the possibility of indiscernibles.

Bertrand Russell argued that any attempt to get rid of universals in favor of resemblances fails. He argued that no resemblance theory could avoid postulating a universal of resemblance without falling prey to a vicious infinite regress. He added that admitting such a universal of resemblance made it pointless to avoid other universals. In this paper I defend resemblance nominalism from both of Russell's points by arguing that (a) resemblance nominalism can avoid the postulation of a universal of resemblance without falling into a vicious infinite regress, and (b) even if resemblance nominalism had to admit a universal of resemblance, this would not make it pointless to avoid postulating other universals.