The Twin Earth thought experiment invites us to consider a liquid that has all of the superficial properties associated with water (clear, potable, etc.) but has entirely different deeper causal properties (composed of “XYZ” rather than of H2O). Although this thought experiment was originally introduced to illuminate questions in the theory of reference, it has also played a crucial role in empirically informed debates within the philosophy of psychology about people’s ordinary natural kind concepts. Those debates have sought to accommodate (...) an apparent fact about ordinary people’s judgments: Intuitively, the Twin Earth liquid is not water. We present results from four experiments showing that people do not, in fact, have this intuition. Instead, people tend to have the intuition that there is a sense in which the liquid is not water but also a sense in which it is water. We explore the implications of this finding for debates about theories of natural kind concepts, arguing that it supports views positing two distinct criteria for membership in natural kind categories – one based on deeper causal properties, the other based on superficial, observable properties. (shrink)

Some experimental studies have recently claimed to undermine semantic externalism about natural kind terms. However, it is unclear how philosophical accounts of reference can be experimentally tested. We present two externalistic adaptations of psychological placeholder essentialism, a strict externalist and a hybrid externalist view, which are experimentally testable. We examine Braisby, Franks, and Hampton's (1996) study which claims to undermine externalism, and argue that the study fails in its aims. We conducted two experiments, the results of which undermine internalism and (...) the hybrid theory, and support strict externalism. Our conclusion is that lay speakers' natural kind concepts involve a belief in an external category essence, which determines reference. (shrink)

One of the central debates in the philosophy of language is that between defenders of the causal-historical and descriptivist theories of reference. Most philosophers involved in the debate support one or the other of the theories. Building on recent experimental work in semantics, we argue that there is a sense in which both theories are correct. In particular, we defend the view that natural kind terms can sometimes take on a causal-historical reading and at other times take on a descriptivist (...) reading. The meaning will shift depending on the conversational setting. The theoretical view has roots in work by Kitcher. We present some original experiments that support the thesis. (shrink)

The essentialist approach to word meaning has been used to undermine the fundamental assumptions of the cognitive psychology of concepts. Essentialism assumes that a word refers to a natural kind category in virtue of category members possessing essential properties. In support of this thesis, Kripke and Putnam deploy various intuitions concerning word use under circumstances in which discoveries about natural kinds are made. Although some studies employing counterfactual discoveries and related transformations appear to vindicate essentialism, we argue that the intuitions (...) have not been investigated exhaustively. In particular, we argue that discoveries concerning the essential properties of whole categories (rather than simply of particular category members) are critical to the essentialist intuitions. The studies reported here examine such discovery contexts, and demonstrate that words and concepts are not used in accordance with essentialism. The results are, however, consistent with "representational change" views of concepts, which are broadly Fregean in their motivation. We conclude that since essentialism is not vindicated by ordinary word use, it fails to undermine the cognitive psychology of concepts. (shrink)

Given the fundamental role that concepts play in theories of cognition, philosophers and cognitive scientists have a common interest in concepts. Nonetheless, there is a great deal of controversy regarding what kinds of things concepts are, how they are structured, and how they are acquired. This chapter offers a detailed high-level overview and critical evaluation of the main theories of concepts and their motivations. Taking into account the various challenges that each theory faces, the chapter also presents a novel approach (...) to concepts that is organized around two ideas. The first is a pluralistic view of differing types of conceptual structure. The second is a model that treats concepts as atomic representations that are linked to various types of conceptual structures. (shrink)

Recent experimental work on “natural” kind terms has shown evidence of both descriptive and nondescriptive reference determination. This has led some to propose ambiguity or hybrid theories, as opposed to traditional description and causal‐historical theories of reference. Many of those experiments tested theories against referential intuitions. We reject this method, urging that reference should be tested against usage, preferably by elicited production. Our tests of the usage of a biological kind term confirm that there are indeed both descriptive and causal‐historical (...) elements to the reference determination of some natural kind terms. We argue that to accommodate our results and earlier ones, we should abandon the common assumption that any one theory of reference fits all natural kind terms. Rather, it is likely that some terms are descriptive, some causal‐historical, some ambiguous, and some hybrid. This substantive conclusion is accompanied by a methodological one. Our experiments, like some earlier ones, found participants contradicting both each other and themselves. We argue that these contradictions indicate a lack of linguistic competence with the term. We conclude that these experiments have been faulty, because they test terms that are novel to participants and/or use fantastical vignettes. We provide some suggestions for future research. (shrink)

Contemporary debates about the nature of semantic reference have tended to focus on two competing approaches: theories which emphasize the importance of descriptive information associated with a referring term, and those which emphasize causal facts about the conditions under which the use of the term originated and was passed on. Recent empirical work by Machery and colleagues suggests that both causal and descriptive information can play a role in judgments about the reference of proper names, with findings of cross-cultural variation (...) in judgments that imply differences between individuals with respect to whether they favor causal or descriptive information in making reference judgments. We extend this theoretical and empirical line of inquiry to views of the reference of natural and nominal kind concepts, which face similar challenges to those concerning the reference of proper names. In two experiments, we find evidence that both descriptive and causal factors contribute to judgments of concept reference, with no reliable differences between natural and nominal kinds. Moreover, we find evidence that the same individuals’ judgments can rely on both descriptive and causal information, such that variation between individuals cannot be explained by appeal to a mixed population of “pure descriptive theorists” and “pure causal theorists.” These findings suggest that the contrast between descriptive and causal theories of reference may be inappropriate; intuitions may instead support a hybrid theory of reference that includes both causal and descriptive factors. We propose that future research should focus on the relationship between these factors, and describe several possible frameworks for pursuing these issues. Our findings have implications for theories of semantic reference, as well as for theories of conceptual structure. (shrink)

Experiments have led some philosophers to conclude that the reference determination of natural kind terms is neither simply descriptive nor simply causal-historical. Various theories have been aired to account for this, including ambiguity, hybrid, and different-idiolects theories. Devitt and Porter (2021) hypothesized that some terms are covered by one theory, some another, with a place for all the proposed theories. The present paper tests hypotheses that the term ‘Rio de Janeiro Myrtle’ is simply causal-historical but the term ‘rice’ is hybrid. (...) For, whereas the former term is of scientific but little practical interest, the latter is not: rice is a significant part of the human diet. So, we predicted there would be two factors to the reference determination of ‘rice’: a superficial-descriptive one and a deep-causal one. Our experiments confirmed these hypotheses using the methods of elicited production and truth value judgments. We take our results to support the hybrid Theory of ‘rice’ rather than the ambiguity or different-idiolects theory. We were not testing ‘myrtle’ but, surprisingly, our results implied that ‘myrtle’ was partly descriptive and so like ‘rice’ but not ‘Rio de Janeiro Myrtle’. A follow-up experiment confirmed these puzzling results. More investigation is needed. (shrink)

The Twin Earth thought experiment invites us to consider a liquid that has all of the superficial properties associated with water (clear, potable, etc.) but has entirely different deeper causal properties (composed of “XYZ” rather than of H2O). Debates about natural kind concepts have sought to accommodate an apparent fact about ordinary people's judgments: Intuitively, the Twin Earth liquid is not water. We present results showing that people do not have this intuition. Instead, people tend to judge that there is (...) a sense in which the liquid is not water but also a sense in which it is water. (shrink)

The present research examines whether identity essentialism, an important component of psychological essentialism, is a fundamental feature of human cognition. Across three studies (Ntotal = 1723), we report evidence that essentialist intuitions about the identity of kinds are culturally dependent, demographically variable, and easily malleable. The first study considered essentialist intuitions in 10 different countries spread across four continents. Participants were presented with two scenarios meant to elicit essentialist intuitions. Their answers suggest that essentialist intuitions vary dramatically across cultures. Furthermore, (...) these intuitions were found to vary with gender, education, and across eliciting stimuli. The second study further examined whether essentialist intuitions are stable across different kinds of eliciting stimuli. Participants were presented with two different scenarios meant to elicit essentialist intuitions—the “discovery” and “transformation” scenarios. Their answers suggest that the nature of the eliciting stimuli influences whether or not people report essentialist intuitions. Finally, the third study demonstrates that essentialist intuitions are susceptible to framing effects. Keeping the eliciting stimulus (i.e., the scenario) constant, we show that the formulation of the question eliciting a judgment influences whether or not people have essentialist intuitions. Implications of these findings for identity essentialism and psychological essentialism, in general, are discussed. (shrink)

In this paper, I argue that the causal and description theories of natural kind term reference involve certain psychological elements. My main goal is to refine these theories with the help of empirical psychology of concepts, and to argue that the refinement process ultimately leads to the dissolution of boundaries between the two kinds of theories. However, neither the refined theories nor any other existing theories provide an adequate answer to the question of what makes natural kind terms rigid. To (...) provide an answer to this question I conclude my paper by introducing a framework of a unified theory of natural kind term reference that is built on the empirical psychology of concepts. (shrink)

E. Machery, R. Mallon, S. Nichols and S. Stich, have argued that there is empirical evidence against Kripke’s claim that names are not descriptive. Their argument is based on an experiment that compares the intuitions about proper name use of a group of English speakers in Hong Kong with those of a group of non-Chinese American students. The results of the experiment suggest that in some cultures speakers use names descriptively. I argue that such a conclusion is incorrect, for the (...) experiment does not prove what it is purported to prove. (shrink)

I examine two sets of experimental results about the semantics of general terms, by Genone and Lombrozo (2012) and by Nichols, Pinillos and Mallon (forthcoming) that allegedly reveal significant variations in semantic intuitions as regards the correct application of general terms. The two sets of authors propose two entirely different semantic treatments: Genone and Lombrozo espouse a hybrid semantics whereas Nichols, Pinillos and Mallon are inclined towards an appeal to ambiguity. I cast some doubts on the coherence of a hybrid (...) theory and argue in favor of the ambiguity approach. But I also argue that the sort of ambiguitiy Nichols, Pinillos and Mallon postulate is easy to incorporate to non-descriptivist approaches. (shrink)

Some experimental studies have recently claimed to undermine semantic externalism about natural kind terms. However, it is unclear how philosophical accounts of reference can be experimentally tested. We present two externalistic adaptations of psychological placeholder essentialism, a strict externalist and a hybrid externalist view, which are experimentally testable. We examine Braisby’s et al. (1996) study which claims to undermine externalism, and argue that the study fails in its aims. We conducted two experiments, the results of which undermine internalism and the (...) hybrid theory, and support strict externalism. Ourconclusion is that lay speakers’ natural kind concepts involve a belief in an external category essence, which determines reference. (shrink)