A stubborn problem for reflectance physicalism about color is to account for individual differences in normal trichromat color perception. The identification of determinate colors with physical properties of visible surfaces in a universal, perceiver-independent way is challenged by the observation that the same surfaces in identical viewing conditions often look different in color to different human subjects with normal color vision. Recently, leading representatives of reflectance physicalism have offered some arguments to defend their view against the individual differences challenge. In (...) this paper I challenge their defense. I argue thateven though individual differences are present in shape perception as well as in color perception, the mechanisms of shape perception and those of color perception differ in ways which make them completely different regarding their evidential status for certain identity claims. Thus comparing color perception to shape perception offers no support for identifying hues with reflectances. On the other hand, drawing a parallel between the temperature-mean kinetic energy of molecules (MKE) identification and the proposed hue-reflectance identities is no support for reflectance physicalism either, since there is an important disanalogybetween the two cases. While individual differences obtain in color perception, the effects of temperature (e.g., melting, thermal expansion) do not exhibit analogous variation, which makes the temperature-MKE identification unproblematic compared to the hue-reflectance identification. One motivation for this ongoing debate is that the success or failure of reflectance physicalism has far-reaching consequences regarding externalist theories of phenomenal consciousness. (shrink)

The “systematicity argument” has been used to argue for a classical cognitive architecture (Fodor in The Language of Thought. Harvester Press, London, 1975, Why there still has to be a language of thought? In Psychosemantics, appendix. MIT Press, Cambridge, pp 135–154, 1987; Fodor and Pylyshyn in Cognition 28:3–71, 1988; Aizawa in The systematicity arguments. Kluwer Academic Press, Dordrecht, 2003). From the premises that cognition is systematic and that the best/only explanation of systematicity is compositional structure, it concludes that cognition is (...) to be explained in terms of symbols (in a language of thought) and formal rules. The debate, with connectionism, has mostly centered on the second premise-whether an explanation of systematicity requires compositional structure, which neural networks do not to exhibit (for example, Hadley and Hayward, in Minds and Machines, 7:1–37). In this paper, I will take issue with the first premise. Several arguments will be deployed that show that cognition is not systematic in general; that, in fact, systematicity seems to be related to language. I will argue that it is just verbal minds that are systematic, and they are so because of the structuring role of language in cognition. A dual-process theory of cognition will be defended as the best explanation of the facts. (shrink)

In this paper we argue that the insistence by Fodor et. al. that the Language of Thought hypothesis must be true rests on mistakes about the kinds of explanations that must be provided of cognitive phenomena. After examining the canonical arguments for the LOT, we identify a weak version of the LOT hypothesis which we think accounts for some of the intuitions that there must be a LOT. We then consider what kinds of explanation cognitive phenomena require, and conclude that (...) three main confusions lead to the invalid inference of the truth of a stronger LOT hypothesis from the weak and trivial version. These confusions concern the relationship between syntax and semantics, the nature of higher-level causation in cognitive science, and differing roles of explanations invoking intrinsic structures of minds on the one hand, and aetiological or evolutionary accounts of their properties on the other. (shrink)

Connectionism seems to avoid many of the problems of classical artificial intelligence, but has it avoided all of them? In this thesis I examine the problem that Intentionality, the directedness of thought to an object, raises for connectionism. As a preliminary approach, I consider the role of Intentionality in classical artificial intelligence from the programmer’s point of view. In this investigation, one problem I identify with classical artificial intelligence is that the Intentionality of the programmer seems to be projected onto (...) the system, rather than the programmer creating a system whereby Intentionality arises intrinsically within the system. -/- In considering the current practice of connectionism, the same problem with Intentionality reappears. The assignment of Intentional content to input or output nodes in a neural network likewise projects the Intentionality of the programmer onto the system, and that projection is often reinforced by the training process of the neural network. However, connectionism seems to have an advantage over classical artificial intelligence in this respect, in that there is a form of neural network in which the network itself organizes the output nodes. The challenge is to utilize these self-organizing networks without having the programmer project Intentionality onto the system in an act of interpretation. -/- I suggest that the way to overcome these problems in connectionism is to embody the neural network within a world, whether physical or virtual, and to allow the system to develop concepts purely empirically. In this manner, connectionism can make scientific observations concerning the nature of cognition without the risk of contamination from the programmer’s own Intentionality. (shrink)

Do we think in a language-like format? Taking the marker of language-like formats to be the property of unconstrained systematicity, this paper considers the following master argument for the claim that we do: language is unconstrainedly systematic, if language is unconstrainedly systematic then so is thought, so thought is unconstrainedly systematic. It is easy to feel that there is something right about this argument, that there will be some way of filling in its details that will vindicate the idea that (...) our thought must be unconstrainedly systematic given that the language in which we express it is. Clearly, however, the second premise needs support—we need a principled reason for moving from the unconstrained systematicity of language to the unconstrained systematicity of thought. This paper gives three passes at formulating such a principle. This turns out to be much harder than it might seem. We should, I conclude, resist falling too easily for the lure of this master argument for the language-like format of thought. (shrink)

A traditional explanation that dates back to Aristotle is that we access color in one perceptual modality only, whereas shape we perceive via two different modalities: visual and tactile. Two independent modalities make possible a verification of our percepts which is not possible for qualities accessed in one modality only.

In this paper I offer an explanation of the ineffability (linguistic inexpressibility) of sensory experiences. My explanation is put in terms of computational functionalism and standard externalist theories of representational content. As I will argue, many or most sensory experiences are representational states without constituent structure. This property determines both the representational function these states can serve and the information that can be extracted from them when they are processed. Sensory experiences can indicate the presence of certain external states of (...) affairs but they cannot convey any more information about them than that. So, format- or code-conversion mechanisms that link different systems of representation (linguistic and perceptual) to each other will fail to extract any relevant information from sensory experiences that could be coded in language. They only way to establish specific roles for sensory experiences in communication and the organization of behavior is to attach to them, by associative links, words, or other behavioral responses. If a sensory experience has no linguistic label associated to it in a particular subject, then no linguistic description can token, or activate, that state in the subject. In other words, no linguistic description can cause a subject to undergo an unlabeled perceptual state. On the contrary, complex, or syntactically structured perceptual states can be built up, on the basis of descriptions, by mechanisms of constructive imagination (conceived here as one sort of format conversion). It is this difference between complex and unstructured representational states that gives us an understanding of the phenomenon we call the ineffability of qualia. (shrink)

Davidson advocates a radical and powerful form of anti-conventionalism, on which the scope of a semantic theory is restricted to the most local of contexts: a particular utterance by a particular speaker. I argue that this hyper-localism undercuts the explanatory grounds for his assumption that semantic meaning is systematic, which is central, among other things, to his holism. More importantly, it threatens to undercut the distinction between word meaning and speaker’s meaning, which he takes to be essential to semantics. I (...) argue that a moderate form of conventionalism can restore systematicity and the word/speaker distinction while accommodating Davidson’s insights about the complexities and contextual variability of language use. (shrink)

I discuss Edouard Machery’s claim that philosophers and psychologists when using the term ‘concept’ are really theorizing about different things. This view is not new, but it has never been developed or defended in detail. Once spelled out, we can see that Machery is right that the psychological literature uses a different notion of concept. However, Machery fails to acknowledge that the two notions are not only compatible but complementary. This fits more with the traditional view according to which philosophers (...) and psychologists are merely interested in different aspects of the same kind. The main aim of this paper is then to show how precisely the two notions of ‘concept’ relate. Distinguishing them resolves the long-standing debate on whether concepts can be prototypes and allows me to formulate success conditions of a theory of categorization that are independent of the success conditions of a theory of concepts. (shrink)