This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

Here I compare two accounts of metaphysical indeterminacy (MI): first, the 'meta-level' approach described by Elizabeth Barnes and Ross Cameron in the companion to this paper, on which every state of affairs (SOA) is itself precise/determinate, and MI is a matter of its being indeterminate which determinate SOA obtains; second, my preferred 'object-level' determinable-based approach, on which MI is a matter of its being determinate---or just plain true---that an indeterminate SOA obtains, where an indeterminate SOA is one whose constitutive object (...) has a determinable property, but no unique determinate of that determinable. In S1, I first note an important difference between our accounts, concerning whether MI is taken to induce propositional indeterminacy; in S2, I highlight and defend certain advantages of my account; in S3, I address certain of Barnes and Cameron's objections to my account. (shrink)

In §2-4, I survey three extant ways of making sense of indeterminate truth and find each of them wanting. All the later sections of the paper are concerned with showing that the most promising way of making sense of indeterminate truth is via either a theory of truthmaker gaps or via a theory of truthmaking gaps. The first intimations of a truthmaker–truthmaking gap theory of indeterminacy are to be found in Quine (1981). In §5, we see how Quine proposes to (...) solve Unger’s problem of the many via positing the possibility of groundless truth. In §6, I elaborate the truthmaker gap model of indeterminacy first sketched by Sorensen (2001, ch.11) and use it to give a reductive analysis of indeterminate truth. In §7, I briefly assess what kind of formal framework can best express the possibility of truthmaker gaps. In §8, I contrast what I dub ‘the ordinary conception of worldly indeterminacy’ with Williamson’s conception of worldly indeterminacy. In §9, I show how one can distinguish linguistic from worldly indeterminacy on a truthmaker gap conception. In §10, I briefly sketch the relationship between truthmaker gaps and ignorance. In §11, I assess whether a truthmaker gap conception of vagueness is really just a form of epistemicism. In §12, I propose that truthmaker gaps can yield a plausible model of (semantic) presupposition failure. In §13, in response to the worry that a truthmaker gap conception of indeterminacy is both parochial and controversial—since it commits us to an implausibly strong theory of truthmaking—I set forth a truthmaking gap conception of indeterminacy. In §14, I answer the worry that groundless truths, of whatever species, are just unacceptably queer. A key part of this answer is that a truthmaker–truthmaking gap model of indeterminacy turns out to be considerably less queer than any model of indeterminacy which gives up on Tarski’s T-schema for truth (and cognate schemas). (shrink)

If the world itself is metaphysically indeterminate in a specified respect, what follows? In this paper, we develop a theory of metaphysical indeterminacy answering this question.

Might it be that world itself, independently of what we know about it or how we represent it, is metaphysically indeterminate? This article tackles in turn a series of questions: In what sorts of cases might we posit metaphysical indeterminacy? What is it for a given case of indefiniteness to be 'metaphysical'? How does the phenomenon relate to 'ontic vagueness', the existence of 'vague objects', 'de re indeterminacy' and the like? How might the logic work? Are there reasons for postulating (...) this distinctive sort of indefiniteness? Conversely, are there reasons for denying that there is indefiniteness of this sort? (shrink)

I argue that an adequate account of non-reductive realization must guarantee satisfaction of a certain condition on the token causal powers associated with (instances of) realized and realizing entities---namely, what I call the 'Subset Condition on Causal Powers' (first introduced in Wilson 1999). In terms of states, the condition requires that the token powers had by a realized state on a given occasion be a proper subset of the token powers had by the state that realizes it on that occasion. (...) Accounts of non-reductive realization conforming to this condition are implementing what I call 'the powers-based subset strategy'. I focus on the crucial case involving mental and brain states; the results may be generalized, as appropriate. I first situate and motivate the strategy by attention to the problem of mental causation; I make the case, in schematic terms, that implementation of the strategy makes room (contra Kim 1989, 1993, 1998, and elsewhere) for mental states to be ontologically and causally autonomous from their realizing physical states, without inducing problematic causal overdetermination, and compatible with both Physicalism and Non-reduction; and I show that several contemporary accounts of non-reductive realization (in terms of functional realization, parthood, and the determinable/determinate relation) are plausibly seen as implementing the strategy. As I also show, implementation of the powers-based strategy does not require endorsement of any particular accounts of either properties or causation---indeed, a categoricalist contingentist Humean can implement the strategy. The schematic location of the strategy in the space of available responses to the problem of mental (more generally, higher-level) causation, as well as the fact that the schema may be metaphysically instantiated, strongly suggests that the strategy is, appropriately generalized and instantiated, sufficient and moreover necessary for non-reductive realization. I go on to defend the sufficiency and necessity claims against a variety of objections, considering, along the way, how the powers-based subset strategy fares against competing accounts of purportedly non-reductive realization in terms of supervenience, token identity, and constitution. (shrink)

Although the Evans argument against vague identity has been much discussed, proposah for blocking it have not so far satisfied general conditions which any solution ought to meet. Moreover, the relation between ontically vague identity and ontic vagueness more generally has not yet been satisfactorily addressed. I advocate a way of resisting the Evans argument which satisfies the conditions. To show how this approach can vindicate particular cases of ontically vague identity, I develop a framework for describing ontic vagueness in (...) general in terms of multiple actualities. This provides aprìncipled approach to ontically vague identity which is unaffected by the Evans argument. (shrink)

Note: this is the first published presentation and defense of the 'proper subset strategy' for making sense of non-reductive physicalism or the associated notion of realization; this is sometimes, inaccurately, called "Shoemaker's subset strategy"; if people could either call it the 'subset strategy' or better yet, add my name to the mix I would appreciate it. Horgan claims that physicalism requires "superdupervenience" -- supervenience plus robust ontological explanation of the supervenient in terms of the base properties. I argue that Horgan's (...) account fails to rule out physically unacceptable emergence. I rather suggest that this and other unacceptable possibilities may be ruled out by requiring that each individual causal power in the set associated with a given supervenient property be numerically identical with a causal power in the set associated with its base property. I go on to show that a wide variety of physicalist accounts, both reductive and non-reductive, are implicitly or explicitly designed to meet this condition, and so are more similar than they seem. In particular, non-reductive physicalism accounts typically appeal to a relation plausibly ensuring that the powers of a higher-level property are a proper subset of those of its physical base property. (shrink)

How can mental properties bring about physical effects, as they seem to do, given that the physical realizers of the mental goings-on are already sufficient to cause these effects? This question gives rise to the problem of mental causation (MC) and its associated threats of causal overdetermination, mental causal exclusion, and mental causal irrelevance. Some (e.g., Cynthia and Graham Macdonald, and Stephen Yablo) have suggested that understanding mental-physical realization in terms of the determinable/determinate relation (henceforth, 'determination') provides the key to (...) solving the problem of MC: if mental properties are determinables of their physical realizers, then (since determinables and determinates are distinct, yet don't causally compete) all three threats may be avoided. Not everyone agrees that determination can do this good work, however. Some (e.g., Douglas Ehring, Eric Funkhauser, and Sven Walter) object that mental-physical realization can't be determination, since such realization lacks one or other characteristic feature of determination. I argue that on a proper understanding of the features of determination key to solving the problem of MC these arguments can be resisted. (shrink)

Terence Parsons, Peter Woodruff; X*—Worldly Indeterminacy of Identity, Proceedings of the Aristotelian Society, Volume 95, Issue 1, 1 June 1995, Pages 171–192.

Terence Parsons, Peter Woodruff; X*—Worldly Indeterminacy of Identity, Proceedings of the Aristotelian Society, Volume 95, Issue 1, 1 June 1995, Pages 171–192.

Perceptions "present" objects as red, as round, etc.-- in general as possessing some property. This is the "perceptual content" of the title, And the article attempts to answer the following question: what is a materialistically adequate basis for assigning content to what are, after all, neurophysiological states of biological organisms? The thesis is that a state is a perception that presents its object as "F" if the "biological function" of the state is to detect the presence of objects that are (...) "F". The theory contrasts with causal/informational theories, and with internalist theories, for example those which assign content on the basis of introspected feel. Its advantages are that it permits perceptual error while at the same time allowing content to be expressed in terms of external properties. The argument of the paper is illustrated throughout by examples from biology and computational psychology. (shrink)

This paper defends the idea that there might be vagueness or indeterminacy in the world itself--as opposed to merely in our representations of the world--against the charges of incoherence and unintelligibility. First we consider the idea that the world might contain vague properties and relations ; we show that this idea is already implied by certain well-understood views concerning the semantics of vague predicates (most notably the fuzzy view). Next we consider the idea that the world might contain vague objects (...) ; we argue that an object is indeterminate in a certain respect (colour, size, etc.) just in case it is a borderline case of a maximally specific colour (size, etc.) property. Finally we consider the idea that the world as a whole might be indeterminate; we argue that the world is indeterminate just in case it lacks a determinate division into determinate objects. (shrink)

E.J. Lowe claims that quantum physics provides examples of ontic indeterminacy, of vagueness in the world. Any such claim must confront the Evans-Salmon argument to the effect that the notion of ontic indeterminacy is simply incoherent (Evans 1978, Salmon 1981: 243-46). Lowe argues that a standard version of the Evans-Salmon argument fails quite generally (Lowe 1994). Harold Noonan (1995) has outlined a non-standard version of the argument, but Lowe argues that this non-standard version fails for specifically quantum mechanical reasons (Lowe (...) 1997). He claims that it is perfectly coherent to suppose that his quantum case is an example of ontic indeterminacy. In this paper, I raise some objections to Lowe's claim. (shrink)

The properties colored and red stand in a special relation. Namely, red is a determinate of colored, and colored is determinable relative to red. Many other properties are similarly related. The determination relation is an interesting topic of logical investigation in its own right, and the prominent philosophical inquiries into this relation have, accordingly, operated at a high level of abstraction.1 It is time to return to these investigations, not just as a logical amusement, but for the payoffs such investigation (...) can yield in solving some basic metaphysical problems. The goal in what follows is twofold. First, I argue for a novel understanding of the determination relation. Second, this understanding is applied to yield insights into property instance (e.g., trope) individuation, how different property types can share an instance, the relation between property types and property instances, as well as applications to causation (mental causation, in particular). (shrink)

The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, radishes, and rubies) are colored, and that colors are physical properties, specifically types of reflectance. This is probably a minority opinion, at least among color scientists. Textbooks frequently claim that physical objects are not colored, and that the colors are "subjective" or "in (...) the mind." The article has two other purposes: first, to introduce an interdisciplinary audience to some distinctively philosophical tools that are useful in tackling the problem of color realism and, second, to clarify the various positions and central arguments in the debate. (shrink)

In this paper I develop a framework for understanding ontic vagueness. The project of the paper is two-fold. I first outline a definitional account of ontic vagueness – one that I think is an improvement on previous attempts because it remains neutral on other, independent metaphysical issues. I then develop one potential manifestation of that basic definitional structure. This is a more robust (and much less neutral) account which gives a fully classical explication of ontic vagueness via modal concepts. The (...) overarching aim is to systematically investigate the puzzling question of what exactly it could be for the world itself to be vague. (shrink)

Colour fascinates all of us, and scientists and philosophers have sought to understand the true nature of colour vision for many years. In recent times, investigations into colour vision have been one of the main success stories of cognitive science, for each discipline within the field - neuroscience, psychology, linguistics, computer science and artificial intelligence, and philosophy - has contributed significantly to our understanding of colour. Evan Thompson's book is a major contribution to this interdisciplinary project. Colour Vision provides an (...) accessible review of the current scientific and philosophical discussions of colour vision. Thompson steers a course between the subjective and objective positions on colour, arguing for a relational account. This account develops a novel `ecological' approach to colour vision in cognitive science and the philosophy of perception. It is vital reading for all cognitive scientists and philosophers whose interests touch upon this central area. (shrink)

Contemporary philosophers commonly suppose that any fundamental entities there may be are maximally determinate. More generally, they commonly suppose that, whether or not there are fundamental entities, any determinable entities there may be are grounded in, hence less fundamental than, more determinate entities. So, for example, Armstrong takes the physical objects constituting the presumed fundamental base to be “determinate in all respects” (1961, 59), and Lewis takes the properties characterizing things “completely and without redundancy” to be “highly specific” (1986, 60). (...) Here I look at the usually cited reasons for these suppositions as directed against the case of determinable properties, in particular, and argue that none is compelling (Sections 1 to 3). The discussion in Section 3 moreover identifies positive reason for taking some determinable properties to be part of a fundamental (or relatively fundamental) base. I close (Section 4) by noting certain questions arising from the possibility of fundamental determinables, as directions for future research. (shrink)

A common conception of what it is for one property to “realize” another suggests that it is the realizer property that does the causal work, and that the realized property is epiphenomenal. The same conception underlies George Bealer’s argument that functionalism leads to the absurd conclusion that what we take to be self-ascriptions of a mental state are really self-ascriptions of “first-order” properties that realize that state. This paper argues for a different concept of realization. A property realizes another if (...) its “forward looking” causal features are a subset of those of the property realized. The instantiation of the realizer property will include the instantiation of the property realized; and when the effects produced are due to the causal features of the latter, it is the instantiation of it that is appropriately regarded as their cause. Epiphenomenalism is avoided, and so is Bealer’s absurd conclusion. (shrink)

Colors are of philosophical interest for two kinds of reason. One is that colors comprise such a large and important portion of our social, personal and epistemological lives and so a philosophical account of our concepts of color is highly desirable. The second reason is that trying to fit colors into accounts of metaphysics, epistemology and science leads to philosophical problems that are intriguing and hard to resolve. Not surprisingly, these two kinds of reasons are related. The fact that colors (...) are so significant in their own right, makes more pressing the philosophical problems of fitting them into more general metaphysical and epistemological frameworks. (shrink)

A common conception of what it is for one property to “realize” another suggests that it is the realizer property that does the causal work, and that the realized property is epiphenomenal. The same conception underlies George Bealer’s argument that functionalism leads to the absurd conclusion that what we take to be self-ascriptions of a mental state are really self-ascriptions of “first-order” properties that realize that state. This paper argues for a different concept of realization. A property realizes another if (...) its “forward looking” causal features are a subset of those of the property realized. The instantiation of the realizer property will include the instantiation of the property realized; and when the effects produced are due to the causal features of the latter, it is the instantiation of it that is appropriately regarded as their cause. Epiphenomenalism is avoided, and so is Bealer’s absurd conclusion. (shrink)