Natural kind terms have exercised philosophical fancy ever since Kripke, in Naming and Necessity, claimed them to be rigid designators. He there drew attention to the peculiar, name-like behavior of a family of prima facie loosely related general terms of ordinary English: terms such as ‘water’, ‘tiger’, ‘heat’, and ‘red’. Just as for ordinary proper names, Kripke argued that such terms cannot be synonymous with any of the definite descriptions ordinary speakers associate with them. Rather, the name-like behavior of these (...) so-called natural kind terms is to be explained, just as in in the case of proper names, by the doctrine of rigid designation. And as a consequence of thus extending the notion of rigid designation to general terms, he famously endorsed the claim that so-called ‘theoretical identifications’, i.e. statements like (1) Water is H2O, are necessary, if true. (shrink)

The semantics of natural kind terms has recently been seen as a problem of reference. Kripke and Putnam have suggested that their meaning begins with rigid designation, with any further implications emerging after empirical study. I part ways with this approach and instead offer an account that focuses on the contribution that these terms make to the inferential roles of different sorts of sentences. I note that natural kind terms play an odd array of grammatical roles, both as subject and (...) as parts of predicates, and explain why this dual role contributes something pragmatically significant to explanations of natural phenomena. (shrink)

This paper discusses whether it can be known a priori that a particular term, such as water, is a natural kind term, and how this problem relates to Putnams claim that natural kind terms require an externalist semantics. Two conceptions of natural kind terms are contrasted: The first holds that whether water is a natural kind term depends on its a priori knowable semantic features. The second.

Externalism is widely endorsed within contemporary philosophy of mind and language. Despite this, it is far from clear how the externalist thesis should be construed and, indeed, why we should accept it. In this entry I distinguish and examine three central types of externalism: what I call foundational externalism, externalist semantics, and psychological externalism. I suggest that the most plausible version of externalism is not in fact a very radical thesis and does not have any terribly interesting implications for philosophy (...) of mind, whereas the more radical and interesting versions of externalism are quite difficult to support. (shrink)

Linsky’s central point is correct; Kripke’s distinction between rigid and nonrigid designators can be extended in a straightforward way from singular terms to general terms. In both cases, for an expression to rigidly designate its extension is for it to designate the same extension with respect to every possible world-state (in which it has an extension at all). On this account, simple natural kind terms like water, gold, electricity, blue, and tiger – as well as ordinary general terms like bachelor, (...) philosopher, automobile and triangle – designate the same extension with respect to each world-state. As I see it, however, the two differ importantly in the metaphysics of their designata. Whereas a term like bachelor designates a property that may be distinguished from other properties that are necessarily coextensive with it, natural kinds differ from one another only if there are possible world-states in which some of their instances are different. Intuitively this seems plausible; it is hard to imagine two distinct species of animal, two distinct substances, or two distinct colors which have precisely the same instances in every possible world-state. This is important for my linguistic model. Consider, for example, the color blue (which I take to be a natural kind). Color science tells us that the object-color blue is determined.. (shrink)

In this fascinating work, Scott Soames offers a new conception of the relationship between linguistic meaning and assertions made by utterances. He gives meanings of proper names and natural kind predicates and explains their use in attitude ascriptions. He also demonstrates the irrelevance of rigid designation in understanding why theoretical identities containing such predicates are necessary, if true.

Joseph LaPorte in an article on `Kind and Rigidity'(Philosophical Studies, Volume 97) resurrects an oldsolution to the problem of how to understand the rigidityof kind terms and other general terms. Despite LaPorte'sarguments to the contrary, his solution trivializes thenotion of rigidity when applied to general terms. Hisarguments do lead to an important insight however. Thenotions of rigidity and non-rigidity do not usefullyapply at all to kind or other general terms. Extendingthe notion of rigidity from singular terms such as propernames to (...) general terms such as natural kind terms is amistake. (shrink)

On Kripke’s intended definition, a term designates an object x rigidly if the term designates x with respect to every possible world in which x exists and does not designate anything else with respect to worlds in which x does not exist. Kripke evidently holds in Naming and Necessity, hereafter N&N (pp. 117–144, passim, and especially at 134, 139–140), that certain general terms – including natural-kind terms like ‘‘water’’ and ‘‘tiger’’, phenomenon terms like ‘‘heat’’ and ‘‘hot’’, and color terms like (...) ‘‘blue’’ – are rigid designators solely as a matter of philosophical semantics (independently of empirical, extra-linguistic facts). As a consequence, Kripke argues, identity statements involving these general terms are like identity statements involving proper names (e.g., ‘‘Clark Kent=Superman’’) in that, solely as a matter of philosophical semantics, they express necessary truths if they are true at all. But whereas it is reasonably clear what it is for a (first-order) singular term to designate, Kripke does not explicitly say what it is for a general term to designate. General terms are standardly treated in modern logic as predicates, usually monadic predicates. There are very forceful reasons – due independently to Church and Godel, and ultimately to Frege – for taking predicates to designate their semantic extensions. But insofar as the extension of the general term ‘‘tiger’’ is the class of actual tigers (or its characteristic function), it is clear that the term does not rigidly designate its extension, since the class of tigers in one possible world may differ from the class of tigers in another. What, then, is it for ‘‘tiger’’ to be rigid? (shrink)

What are the criteria determining the individuation of chemical kinds? Recent philosophical discussion, which puts too much emphasis on microstructure, seems to presuppose a reductionist conception not motivated by the scientific facts. The present article traces the development of the traditional notion of a substance with the rise of modern chemistry from the end of the 18th century with a view to correcting this speculative distortion.

According to microessentialism, it is necessary to resort to microstructure in order to adequately characterise chemical substances such as water. But the thesis has never been properly supported by argument. Kripke and Putnam, who originally proposed the thesis, suggest that a so-called stereotypical characterisation is not possible, whereas one in terms of microstructure is. However, the sketchy outlines given of stereotypical descriptions hardly support the impossibility claim. On the other hand, what naturally stands in contrast to microscopic description is description (...) in macroscopic terms, and macroscopic characterisations of water are certainly possible. This suffices to counter the claim that microdescriptions are necessary. Whether it counters the impossibility claim depends on whether all macroscopic descriptions are stereotypical (stereotypical descriptions presumably being macroscopic). In so far as systematic import of “stereotypical” can be determined, it would seem not. But some macroscopic characterisations have definite affinity with everyday knowledge, which presumably stands in conflict with the spirit of the impossibility claim. Since what is characterised are properties expressed by predicates like “is water”, the necessity of identity has no bearing here, and matters of interpretation pose problems for claims to the effect that science fixes the extension of “water” as ordinarily understood. (shrink)

In this paper I examine two ways of defining the rigidity of general terms. First I discuss the view that rigid general terms express essential properties. I argue that the view is ultimately unsatisfactory, although not on the basis of the standard objections raised against it. I then discuss the characterisation in terms of sameness of designation in every possible world. I defend that view from two objections but I argue that the approach, although basically right, should be interpreted cautiously.

According to Scott Soames’ Beyond Rigidity, there are two important pieces of unfinished business left over from Saul Kripke’s influential Naming and Necessity. Soames reads Kripke’s arguments about names as primarily negative, that is, as proving that names don’t have a meaning expressible by definite descriptions or clusters of them. The famous Kripkean doctrine that names are rigid designators is really only part of the negative case. The thesis that names refer to the same object with respect to every possible (...) world is a byproduct of their meaning, not a positive account of what they mean. As well, the hints about causal chains and dubbings are no more than a picture, as Kripke says, and not a positive theory of meaning. Thus one piece of unfinished business, to which Soames devotes the most attention, is to give a positive account of the meanings of names. To do this Soames proposes that the meaning of a singular term is the contribution it makes to the semantic content of the sentences in which it occurs. The semantic content of a sentence is ordinarily a proposition, that proposition expressed by the most commonly intended assertion using the sentence. Soames’ proposal for a positive account is that the meaning of a proper name is its contribution to those propositions, simply the object to which it refers. Arguing for this positive account occupies the bulk of the book but I will not discuss it in my contribution to this symposium. (shrink)

Dry earth seems to its inhabitants (our intrinsic duplicates) just as earth seems to us, that is, it seems to them as though there are rivers and lakes and a clear, odorless liquid flowing from their faucets. But, in fact, this is an illusion; there is no such liquid anywhere on the planet. I address two objections to externalism concerning the nature of the concept that is expressed by the word 'water' in the mouths of the inhabitants of dry earth. (...) Gabriel Segal presents a dilemma for the externalist concerning the application conditions of the concept, and Paul Boghossian presents a dilemma for the externalist concerning the complexity of the concept. I show that, in both cases, the externalist may occupy the horn of his choice without departing from either the letter or spirit of externalism. (shrink)

It is widely held that the meaning of certain types of terms, such as natural kind terms, is individuated externalistically, in terms of the individual's external environment. Recently a more radical thesis has emerged, a thesis we dub 'a posteriori semantics.' The suggestion is that not only does a term's meaning depend on the external environment, but so does its semantics. One motivation for this is the aim to account for cases where a putative natural kind term fails to pick (...) out a natural kind: The term may have a standard externalist semantics (if it picks out a natural kind) or a more descriptivist one (if it does not). Knowing which semantics applies will therefore require detailed empirical knowledge. This move has also been employed in cases where a singular term, such as a name, fails to have a reference. We argue that a posteriori semantics is inherently implausible, since the type of semantics common terms should be given ought not to be conditional on details of chemistry or physics. A number of difficulties for the position—'metaphysical,' epistemological, and methodological—are articulated. Finally, we suggest that a posteriori semantics misconstrues the way in which semantics is empirical. (shrink)

What is it for a predicate or a general term to be a rigid designator? Two strategies for answering this question can be found in the literature, but both run into severe difficulties. In this paper, it is suggested that proper names and the usual examples of rigid predicates share a semantic feature which does the theoretical work usually attributed to rigidity. This feature cannot be equated with rigidity, but in the case of singular terms this feature entails their rigidity, (...) as understood in the standard characterisation. Hence, it is appropriate to call this feature proto-rigidity. (shrink)

The Philosophical search for Natural Kinds is motivated by the hope of finding ontological categories that are independent of our interests. Other requirements, of varying importance, are commonly made of kinds that claim to be natural. But no such categories are to be found. Virtually any kind can be termed ‘natural’ relative to some set of interests and epistemic priorities. Science determines those priorities at any particular stage of its progress, and what kinds are most ‘natural’ in that sense is (...) always a real and lively scientific question. The general philosophical problem of scientific realism is also real; but between the scientific and the metaphysical, the ‘Problem of Natural Kinds’ sits otiose. (shrink)

The Philosophical search for Natural Kinds is motivated by the hope of finding ontological categories that are independent of our interests. Other requirements, of varying importance, are commonly made of kinds that claim to be natural. But no such categories are to be found. Virtually any kind can be termed 'natural' relative to some set of interests and epistemic priorities. Science determines those priorities at any particular stage of its progress, and what kinds are most 'natural' in that sense is (...) always a real and lively scientific question. The general philosophical problem of scientific realism is also real; but between the scientific and the metaphysical, the Problem of Natural Kinds' sits otiose. (shrink)

Two ways of characterizing natural kinds are currently popular: the Kripke-Putnam appeal to microstructure and Boyd’s appeal to causal homeostasis. I argue that these conceptions are more divergent than is often acknowledged, that they give no credence to essentialism, and that they are both faulty. In their place, I sketch an alternative view of natural kinds, which I call “bare projectibilism”. This conception avoids the appeal to explanation common to microstructuralism and the causal homeostasis view, but is still compatible with (...) scientific realism. (shrink)

There is a form of argument for a certain kind of essentialist conclusion which appears not to depend upon any appeal to intuition. Identity statements involving natural kind terms are often adverted to in the literature as examples of the necessary a posteriori, and it can appear as though the essentialist is on very strong ground with respect to these claims. It is not merely that they are apt to strike one as plausible in the light of philosophical arguments or (...) modal intuitions; rather, they appear to be provable, given only fairly trivial logical principles and uncontroversial scientific truths. This paper attempts to counter the claim, made particularly convincing by the work of Saul Kripke, that this indeed the case. (shrink)

Fodor’s theory of concepts holds that the psychological mechanisms which guide us in applying concepts to objects do not determine reference; instead, causal relations of a specific kind between properties and our dispositions to token a concept are claimed to do so. Fodor does admit that there needs to be some psychological mechanism mediating the property – concept tokening relations, but argues that it is purely accidental for reference. In contrast, I argue that the actual mechanisms that sustain the reference (...) determining concept tokening relations are necessary for reference. Thus, to possess a concept it is necessary to possess some specific sustaining mechanism. (shrink)