Objetivo de ventas

Here I want to argue that concerns about metaphysics are internal to linguistics, be- cause different metaphysics lead to different views concerning the embedding behaviour of referring expressions under temporal expressions, and the study of embedding be- haviour is a fundamental part of formal semantics2_{. Assume stage theory. Then my}

claim is that the semantic content of a name is a modally constant function from worlds to the stage currently picked out by a name. A consequence of this is that, relative to a non-actual world in which endurance theory is true (and in addition there are no temporal parts), ’Joan’ doesn’t pick out anything.

This, I fully realise, can be challenged. One might think that ’Joan’ relative to this world picks out the stage; relative to the endurance world it picks out the endurant, and so on. But I don’t think this is ultimately a happy position, because it doesn’t make sense of externalism. Externalism about natural kinds tells us that there are chemi- cal facts out there, facts about, say, the nature or essence of the clear potable liquid around us. And it says that that’s what our semantics latches on to. But then there are metaphysical facts out there, so why shouldn’t externalism say that they are what our semantics latches on to?

Firstly, we can note that from the point of view of language users, there doesn’t seem to be any great difference between chemistry and metaphysics. The average speaker knows about as little, and cares about as little, about the chemistry facts and the metaphysical facts (admittedly, we might say the patient cares rather a great deal about arthritis, but really it’s generally what’s hurting him that he cares about; more- over, sometimes we do care about metaphysical matters, as the vacillating believer does about the existence of God). Moreover, if we go back in time to prior to the discovery of organic chemistry, just as the speaker’s dispositions to behave will be the same on Twin Earth world, so, assuming just for the sake of argument stage theory is true, they will be the same in an endurantist world.

Secondly, I take it it’s not too outlandish to say that metaphysics and chemistry lie on a continuum of investigation. In particular, I take it that most people who take analytic metaphysics seriously will assume that there is some fact of the matter about

1_{For some pertinent references: counterexamples are suggested by Evans’s Madagascar case (Evans,}

1973), and slightly more recondite ones to natural kind terms by Unger (Unger, 1984). Some experimental philosophers (e.g. Machery et al., 2004) claim to have shown judgements concerning these thought ex- periments are culturally relative; for some dissenting discussion see (Ichikawa, Maitra, and Weatherson, 2012). Other responses involve beefing up one’s ontology to recognise, alongside H20 and XYZ, sub- stances whose chemical composition is modally variable, being H20 on earth and XYZ on Twin Earth, or again to recognise diseases such as tharthritis in addition to arthritis (Unger, 1984,Crane, 1991). And yet others are somewhat concessionary, trying to uphold the central externalist idea without giving up com- pletely on internalism: among these I would count causal descriptivism (defended inter alia in (Lewis, 1997) and (Kroon, 1987), as well as two dimensional semantics (see, e.g. (Chalmers, 2006).

2_{Examples could be presented ad nauseam, but think of: Tarski’s semantics for the behaviour of vari-}

ables under co-indexed quantifiers, the realisation that indefinites exhibited odd behaviour in scope is- lands, the Frege-Geach problem, the problem of de re attitude reports, the behaviour of epistemic modals under ’suppose’ etc.

whether or not objects are endurants or are stages, just as everybody will take it seri- ously that there’s some fact underlying whether a particular sample of a shiny metal is actually gold, or fake gold (not everyone, of course: some may take metaphysics se- riously yet still think the debate concerning persistence is merely verbal). Given that we’ve recognised our semantics is sensitive to these latter facts, we should say the same about the former facts. In short, from the perspective both of the speakers of language (they are ignorant of chemistry and metaphysics) and of the world (it contains chemi- cal and metaphysical facts), chemistry and metaphysics are on a par. Since we accept externalism concerning the latter, there is no reason not to accept to concerning the former.

Moreover, it’s important to realise that this has important semantic consequences: it’s not something which semanticists can just safely ignore. In particular, given ex- ernalism about metaphysics facts, which metaphysics is correct has consequences for whether names are temporally rigid (Varzi, 2003). For we can note that stage theory would seem to imply that namesaren’ttemporally rigid. In particular, it’s sensible to say that a name like ’Barack Obama’, relative to now, refers to Barack’s current stage, while relative to six minutes ago, it referred to the stage that existed then. Since stages are instantaneous, these must be different stages, and so we have temporal non-rigidity. By contrast, if names are endurants, we can easily say that ’Barack Obama’ refers to the same thing at both times.

And this has important technical semantic consequences. As we’ll saw, one of the ways for classifying determiner phrases as referring or not is whether or not they are rigid. In particular, it’s often been taken to be an important distinction between names and definite descriptions that the former are de jure rigid, while the latter are not. But if stage theory is true, then this is not so. A semanticist who believes in externalism, then, would be well advised to keep an eye on how the persistance debate turns out.

4.5

Conclusion

I’ve argued that semantics guides metaphysics, and vice versa. Both of these claims will be used going forward. Assuming the truth of four dimensionalism, that metaphysics guides semantics means that our language must talk about temporal parts, because temporal parts are what’s out there, and our language talks about what’s out there. That semantics guides metaphysics will be used to decide between different views about temporal parts: in the next chapter, I’ll make the paradigm move of showing that there’s certain data which can’t be accommodated under extant four dimension- alisms, in the same way Davidson showed there’s data which can’t be accommodated under extant semantics of adverbs. Then later I’ll show that a new sort of four dimen- sionalism can account for this data, and thus that we are given some reason to believe in it.

Problems For Stage and Worm

Theory

5.1

Introduction

We can quite naturally understand both stage and worm theory as making certain se- mantic claims. The stage theorist says that a referring expression such as a name stands, at a time, for the stage which is exists at that time. For example, an utterance of ’Obama’ at t1 stands for the Obama stage which exists at t1. The worm theorist, by contrast, since she thinks that Obama is a worm, should say that ’Obama’ always stands for that worm. In this chapter, I’ll show that neither of these approaches are tenable: once one tries to develop either idea into a workable semantic theory, problems soon arise. The next chapter will present a semantics that takes four dimensionalism seriously and doesn’t fall prey to these problems.