The phrase "natural kind term" has come into the linguistic and philosophical literature in connection with well-known work of Kripke (1972) and Putnam (1970, 1975a). I use that phrase here in the sense it has acquired from those and subseqnent works on related topics. This is not the transparent sense of the phrase. That is, if I am right in what follows there are words for kinds of things existing in nature which are not natural kind terms in the current (...) sense - e.g. planet, woman, and weed. I use the term "nondescriptional", following Salmon (1981), to mean "lacking a Fregean sense", where a Fregean sense is taken to be a property or group of properties semantically associated with an expression which determines its denotation. I hope that the term "nondescriptional" will be clarified in subsequent discussion, but perhaps a few words about it and its opposite, "descriptional", would be useful here. These terms (as Salmon notes (p.15, n. 11)) should be taken as technical terms. The idea is that descriptional words, of which bachelor is the overwhelmingly favorite example, express a semantic content, or sense, which is what mediates their denotation. Entities fall in their denotation in virtue of possessing the property or properties expressed as their sense. (It is not necessary, however, that this sense be as easily paraphrasable with descriptive synonyms as it is typically held to be in the case of bachelor, or even that it be paraphrasable at all.) In the case of nondescriptional words there is no Fregean sense to mediate the link between word and object. Hence such terms are described by what Salmon, following Kaplan, calls "the theory of direct reference". What it is that does associate such terms with their denotations is another question which will be touched on briefly at the end. I have several aims in this paper. The first is to defend a conservative position on nondescriptionality. I will argue that relatively few natural language words have this property. My other aims are primarily clarificatory. Among the issues I would like to clarify are those connected with the determination of this property and flae explanation of why it exists, its relationship with other properties such as rigid designation and essentiality, and its significance for lexical semantics. The organization of the paper is as follows. The first section identifies the position taken here on the question of which expressions are nondescriptional and provides a general defense of it. The second section is a critical examination of criteria associated with nondescriptionality. In the third section provide further defense for the conservative position, and in the fourth section we turn to related issues in lexical semantics. (shrink)

The article discusses an idea of how to extend the notion of rigidity to predicates, namely the idea that predicates stand in a certain systematic semantic relation to properties, such that this relation may hold rigidly or nonrigidly. The relation (which I call signification) can be characterised by recourse to canonical property designators which are derived from predicates (or general terms) by means of nominalization: a predicate signifies that property which the derived property designator designates. Whether signification divides into rigid (...) and non-rigid cases will then depend uponwhether canonical property designators divide into rigid and non-rigid ones. But, I shall argue, they do not, and so the only notion of rigidity gained this way is trivial. To show this, I first focus on the kind of canonical property designators which could be thought to be nonrigid, canonical designators such as having the colour of ripe tomatoes which themselves contain non-rigid property designators. An argument to the effect that such complex canonical designators are non-rigid is rebutted, five arguments to the effect that they are rigid are formulated, and finally an explanation of their rigidity based on the general nature of canonical property designators is presented. (shrink)

In a recent article, Alex Levine raises a paradox. It appears that, given some relatively uncontroversial premises about how a species term comes to refer to its species, a type specimen belongs necessarily and contingently to its species. According to Levine, this problem arises if species are individuals rather than natural kinds. I argue that the problem can be generalized: the problem also arises if species are kinds and type specimens are paradigmatic members used to baptize names for species. Indeed, (...) the same problem arises with respect to kinds like gold and the samples used to ground names for them. After arguing that the paradox arises whether or not species are individuals, I attempt to show how the paradox can be resolved. Levine's argument that a type specimen belongs necessarily to its species is specious. The appeal of the argument stems from a failure to distinguish between two different modal statements concerning type specimens, one de dicto and the other de re. Type specimens belong contingently to their respective species. Even so, they can be known a priori to belong to them: hence, that a particular type specimen belongs to its species is an example of contingent a priori knowledge. (shrink)

According to a doctrine that has been popularized by Kripke and Putnam, a natural kind term like 'bird' rigidly designates the kind with the microstructure of sample birds. This microstructure is the essence of birdhood, so our learning what the relevant microstructure is our discovery of the kind's essence. We have discovered that some statement like 'The bird is the taxon with such and such DNA structure' is true. Further, it is commonly added, the discovered microstructure is essential to each (...) particular bird. ;I argue that this general picture is mistaken. I do accept and defend the view that terms like 'bird' are rigid designators. However, the picture at issue has other difficulties. Individual birds are not essentially birds. And the view that biologists have discovered or will discover that the bird kind is identical to some DNA structure or other type of structure seems wrong. We don't discover just what particular characteristic a kind is to be identified with. Rather, the meaning of natural kind terms changes; as science advances, more sophisticated concepts attending kind terms replace older ones. So the Kripke-Putnam account of our discovering the truth of theoretical identity statements seems wrong. ;Fortunately, the account retains some interest despite its falsity, because of its association with the claim that statements like 'The bird is the taxon with such and such DNA structure' are necessary but a posteriori. The above sentence does not express a truth, much less a necessary truth, but the idea that it could have expressed the sort of necessary a posteriori truth it is supposed to express is epistemologically interesting. The very possibility of such necessary a posteriori knowledge deserves some account. I offer an account, arguing that this sort of knowledge is no more impressive from an epistemological standpoint than is knowledge of analytic necessity: indeed, I argue, it is best understood as knowledge of a species of analytic necessity. Independently of this claim, I argue in a concluding discussion that analyticity ought to be accepted by proponents of the necessary theoretical identity statements in question. (shrink)

Kripke defines a rigid designator as one that designates the same object in every possible world in which that object exists. He argues that proper names are rigid. So also, he claims, are various natural kind terms. But we wonder how they could be. These terms are general and it is not obvious that they designate at all. It has been proposed that these kind terms rigidly designate abstract objects. This proposal has been criticized because all terms then seem to (...) come out rigid, thus trivializing rigidity. The paper starts with further criticisms of this proposal aimed particularly at a recent version given by LaPorte. The paper goes on to develop and defend an alternative proposal presented briefly in Devitt and Sterelny (1999): instead of taking those natural kind terms to rigidly designate an object we take them to rigidly apply to the members of their extensions. Schwartz has rightly insisted that a notion of rigidity must do some theoretical work if it is to be interesting. The paper argues that rigid application for kind terms does the same primary work as rigid designation for singular terms, the work of refuting description theories of some terms; and it does the same secondary work, of explaining certain modal phenomena (with one exception). (shrink)

En este escrito se argumentará que uno de los problemas centrales de la rigidez en los términos generales para clases naturales es consecuencia de no distinguir entre términos rígidos de jure y términos rígidos de facto en dichos casos. Se sostiene que los enunciados de identidad necesarios defendidos por Kripke en Naming and Necessity consideran la ocurrencia de términos que designan a una misma clase (clases que poseen entre sí la relación transmundana de ser una misma clase) a través de (...) dos términos rígidos, uno de jure y uno de facto. Esto permite explicar los problemas que la noción de rigidez plantea en los casos de los términos generales para clases naturales, pues mantiene los requerimientos de conexión causal y a su vez enuncia el criterio de identidad entre tales clases, a través de la(s) propiedad(es) esencial(es) de dicha clase. (shrink)