Gareth Evans proved that if two objects are indeterminately equal then they are different in reality. He insisted that this contradicts the assumption that there can be vague objects. However we show the consistency between Evans's proof and the existence of vague objects within classical logic. We formalize Evans's proof in a set theory without the axiom of extensionality, and we define a set to be vague if it violates extensionality with respect to some other set. There exist models of (...) set theory where the axiom of extensionality does not hold, so this shows that there can be vague objects. (shrink)

Lewis proposed to test the validity of a modal thesis by checking whether its possible-world translation is a theorem of counterpart theory. However, that criterion fails to validate many standard modal laws, thus raising doubts about the logical adequacy of the Lewisian framework. The present paper considers systems of counterpart theory of increasing strength and shows how each can be motivated by exhibiting a suitable intended model. In particular, perfect counterpart theory validates all the desired modal laws and therefore provides (...) a way out of the logical objection. Finally, a weakening of perfect counterpart theory is put forward as a response to some metaphysical objections. (shrink)

Can we solve the Problem of the Many, and give a general account of the indeterminacy in definite descriptions that give rise to it, by appealing to metaphysically indeterminate entities? I argue that we cannot. I identify a feature common to the relevant class of definite descriptions, and derive a contradiction from the claim that each such description is satisfied by a metaphysically indeterminate entity.

In the paper Evans’s argument concerning indeterminate identity statements is presented and discussed. Evans’s paper in which he formulated his argument is one of the most frequently discussed papers concerning identity. There are serious doubts concerning what Evans wanted to prove by his argument. Theorists have proposed two competing and incompatible interpretations. According to some, Evans purposefully constructed an invalid argument in order to demonstrate that the vague objects view cannot diagnose the fallacy and is therefore untenable. According to others, (...) Evans wanted to formulate a (valid) argument to the effect that there cannot be vague identity statements whose vagueness is due solely to the existence of vague objects. As it has been argued, if it is the former interpretation which is correct, than the argument really is invalid, but it is doubtful whether it achieves its aim. It might be claimed that “the vague objects view” it refutes is not the view that most vague objects theorists hold. The main part of the paper is devoted to the second interpretation and the discussions concerning the validity of the argument on this interpretation. It appears that the vague objects theorist is in a position to object to the validity of every single step of the proof. (shrink)

This volume analyzes and studies how vagueness occurs and matters as a specific problem in the context of theories that are primarily about something else.

Traditionally, this puzzle has been solved in various ways. Aristotle, for example, distinguished between “accidental” and “essential” changes. Accidental changes are ones that don't result in a change in an objects' identity after the change, such as when a house is painted, or one's hair turns gray, etc. Aristotle thought of these as changes in the accidental properties of a thing. Essential changes, by contrast, are those which don't preserve the identity of the object when it changes, such as when (...) a house burns to the ground and becomes ashes, or when someone dies. Armed with these distinctions, Aristotle would then say that, in the case of accidental changes, (1) and (2) are both false—a changing thing can really change one of its “accidental properties” and yet literally remain one and the same thing before and after the change. (shrink)

In this paper, I assess the analysis of vagueness of objects in terms of the theory of constitution with respect to the notion of vague identity. Some proponents of the constitution theory see it as an advantage of their account that analysing the spatial and temporal vagueness of objects in terms of the relation of vague constitution avoids commitment to vague identity, which is seen as a controversial notion. I argue that even though the constitution theory may plausibly be applied (...) to the phenomenon of vague boundaries, it fails to account fully for other cases of spatial and temporal vagueness. There are what I call ‘mid-extension’ vagueness cases, in which the tools of the constitution theory applied in the analysis of boundary vagueness are insufficient to avoid commitment to vague identity. (shrink)

Few views are as widely held as the Standard View of Identity. Here I am concerned with minority views that depart from the standard account. First, I attempt to illuminate such views and the debates concerning them by identifying the principles of identity at issue, articulating some of the assumptions underlying the debates, and presenting some of the evidence used against the Standard View of Identity. Second, I enter two of these debates myself. I first defend two Non-Standard Views of (...) Identity from the charge that they violate a principle of identity, namely the Transitivity of Identity. I then present an overlooked consequence of another Non-Standard View of Identity that challenges the view on one of its own methodological principles. Third, I draw on recent work in ontological and parthood pluralism to show how one might be led to think that there is more than one way of being identical. That is, I show how one might be an identity pluralist. (shrink)