Online research in philosophy

Suppose that we repair a wooden ship by replacing its planks one by one with new ones while at the same time reconstructing it using the discarded planks. Some defenders of vague or indeterminate identity claim that: (1) although the reconstructed ship is distinct from the repaired ship, it is indeterminate whether the original ship is the reconstructed ship and indeterminate whether it is the repaired ship, and (2) the indeterminacy is due to the world and not just an imprecision in the language used to describe the situation. I argue that such a description is incoherent. The argument has two features. First, it differs in spirit from Gareth Evans's more general famous proof against the possibility of indeterminate identity. This is because I rely on facts regarding counting and sets. Second, I focus on Terence Parsons's recent defence of indeterminate identity. I argue that his attempts at making sense of counting objects involving indeterminate identities fail on technical and philosophical grounds.

There has been much discussion of whether there could be objects A and B that are “individuatively vague” in the following way: object A and object B neither determinately stand in the relation of identity to one another, nor do they determinately fail to stand in this relation. If there are objects of this type, then we would have a genuine case of metaphysical vagueness, or “vagueness-in-the-world.” The possibility of vague objects in this sense strikes many as incoherent. The possibility’s very description not only seems to talk of two objects but, much worse, it seems to point to a feature that distinguishes them: unlike object A, object B is not determinately identical to object A. This suspicion of incoherence is voiced in the famous arguments given against the possibility by Gareth Evans and Nathan Salmon. But the status of those arguments and others is uncertain. Here I present a new argument against vague objects — or more precisely, against the possibility of individuatively vague objects that satisfy an important and common additional condition that I will call “Democracy.” Since my argument turns on a connection between what is indeterminate and what is possible, I call it “the modal argument.”.

Vagueness as Indeterminacy. I defend the traditional view that a vague term is one with an indeterminate denotation from a bevy of recent challenges.

A plausible thought about vagueness is that it involves a form of semantic incompleteness. To say that a predicate is vague is to say (at the very least) that its extension is incompletely specified. And where there is incomplete specification of extension there is indeterminacy—an indeterminacy between various ways that the specification of the predicate might be completed or, as some like to say, sharpened (or precisified). We shall argue that this idea is defective insofar as there are vague predicates that cannot be sharpened. At least, there are predicates that are vague but that cannot be sharpened in such a way as to meet certain basic constraints that we think must be imposed on the very notion of a sharpening.

There has been recent interest in formulating theories of non-representational indeterminacy. The aim of this paper is to clarify the relevance of quantum mechanics to this project. Quantum-mechanical examples of vague objects have been offered by various authors, displaying indeterminate identity, in the face of the famous Evans argument that such an idea is incoherent. It has also been suggested that the quantum-mechanical treatment of state-dependent properties exhibits metaphysical indeterminacy. In both cases it is important to consider the details of the metaphysical account and the way in which the quantum phenomenon is captured within it. Indeed if we adopt a familiar way of thinking about indeterminacy and apply it in a natural way to quantum mechanics, we run into illuminating difficulties and see that the case is far less straightforward than might be hoped.

The supporter of vague objects has been long challenged by the following ‘Argument from Identity’: 1) if there are vague objects, then there is ontically indeterminate identity; 2) there is no ontically indeterminate identity; therefore, 3) there are no vague objects. Some supporters of vague objects have argued that 1) is false. Noonan (Analysis 68: 174–176, 2008) grants that 1) does not hold in general, but claims that ontically indeterminate identity is indeed implied by the assumption that there are vague objects of a certain special kind (i.e. vague objects*). One can therefore formulate a ‘New Argument from Identity’: 1′) if there are vague objects*, then there is ontically indeterminate identity; 2) there is no ontically indeterminate identity; therefore, 3′) there are no vague objects*. Noonan’s strategy is to argue that premiss 1′) is inescapable, and, as a consequence, that Evans’s alleged defence of 2) is a real challenge for any supporter of vague objects. I object that a supporter of vague objects who grants the validity of Evans’s argument allegedly in favour of 2) should reject premiss 1′). The threat of the New Argument from Identity is thus avoided.

I will here present a number of problems concerning the idea that there is ontological vagueness, and the related claim that appeal to this idea can help solve some vagueness-related problems. A theme underlying the discussion will be the distinction between vagueness specifically and indeterminacy more generally (and, relatedly, the distinction between ontological vagueness and ontological indeterminacy). Even if the world is somehow ontologically indeterminate it by no means follows that it is, properly speaking, ontologically vague.1..

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?

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.

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.