Online research in philosophy

Reflectance physicalism only provides a partial picture of the ontology of color. Byrne & Hilbert’ account is unsatisfactory because the replacement of reflectance functions by productance functions is ad hoc, unclear, and only leads to new problems. Furthermore, the effects of color contrast and differences in illumination are not really taken seriously: Too many “real” colors are tacitly dismissed as illusory, and this for arbitrary reasons. We claim that there cannot be an all-embracing ontology for color.

A consideration of the benefits of taking physicalism to be necessarily true if true, against the standard view that physicalism is at best contingently true. Presented at the 2006 Central Division meeting of the APA, in the session Themes from Jaegwon Kim, sponsored by the Society for Asian and Asian-American Philosophy.

In this paper I argue that all transparent objects are colorless. This thesis is important for at least three reasons. First, if transparent objects are colorless, there is no need to distinguish between colors which characterize three-dimensional bodies, like transparent colors, and colors which lie on the surface of objects. Second, traditional objections against color physicalism relying on transparent colors are rendered moot. Finally, an improved understanding of the relations between colors, light and transparency is provided.

A physicalist view of qualia labelled non-eliminative reductionism is outlined. If it is true, qualia and physicalism can co-exist without difficulty. First, qualia present no particular problem for reductionist physicalism - they are entirely physical, can be studied and explained using the standard scientific approach, and present no problem any harder than any other scientists face. Second, reductionist physicalism presents no particular problem for qualia – they can be encompassed within an entirely physicalist position without any necessity, either to reduce them to non-existence, or to treat them as new fundamental properties. It is suggested that the position also has sufficient explanatory power to successfully deal with the 'why like anything – why does experience exist at all' question and to counter both Chalmers' Conceivability Argument and Jackson's Knowledge Argument.

Dualists say plausible things about our mental concepts: there is a way of thinking of pain, in terms of how it feels, which is independent of causal role. Physicalists make attractive ontological claims: the world is wholly physical. The attraction of a posteriori physicalism is that it has seemed to do both: to agree with the dualist about our mental concepts, whilst retaining a physicalist ontology. In this paper I argue that, in fact, a posteriori physicalism departs from the dualist's intuitive picture of our phenomenal concepts in just as radical a manner as more traditional forms of physicalism. Whereas the physicalism of David Lewis and David Armstrong is counterintuitive in holding that our only way of thinking about pain is in terms of its causal role, the physicalism of David Papineau and Brian Loar departs from common sense in holding that our phenomenal concept of pain is opaque: thinking of pain in terms of how it feels reveals nothing of what it is for something to feel pain. The arguments of David Chalmers and Frank Jackson against a posteriori physicalism involve general claims about all concepts. In contrast, my argument makes a claim only about phenomenal concepts: phenomenal concepts are not opaque.

David Chalmers' conceivability argument against physicalism relies on the entailment from a priori conceivability to metaphysical possibility. The a posteriori physicalist rejects this premise, but is consequently committed to psychophysical strong necessities. These don't fit into the Kripkean model of the necessary a posteriori, and they are therefore, according to Chalmers, problematic. But given semantic assumptions that are essential to the conceivability argument, there is reason to believe in microphysical strong necessities. This means that some of Chalmers' criticism is unwarranted, and the rest equally afflicts the dualist. Moreover, given that these assumptions are independently plausible, there's a general case to be made for the existence of strong necessities outside the psychophysical domain.

2. The Contingency and A posteriority Constraint: A formulation of the thesis must make physicalism come out contingent and a posteriori. First, physicalism is a contingent truth, if it is a truth. This means that physicalism could have been false, i.e. there are counterfactual worlds in which physicalism is false, for example, counterfactual worlds in which there are <span class='Hi'>miracle</span>-performing angels.[9] Moreover, if physicalism is true, our knowledge of its truth is a posteriori. This is to say that there are ways the world could turn out to be such that physicalism is false. For example, if there are <span class='Hi'>miracle</span>-performing angels, then physicalism is false. So there are worlds considered as actual in which physicalism is false.[10] For short, call this ‘the a posteriority constraint’.[11].

Our reply is in three parts. The first part concerns some foundational issues in the debate about color realism. The second part addresses the many objections to the version of physicalism about color ("productance physicalism") defended in the target article. The third part discusses the leading alternative approaches and theories endorsed by the commentators.

We make three points. First, the concept of productance value that the authors propose in their defense of color physicalism fails to do the work for which it is intended. Second, the authors fail to offer an adequate physicalist account of what they call the hue-magnitudes. Third, their answer to the problem of individual differences faces serious difficulties.