Brain activity determines which relations between objects in the environment are perceived as differences and similarities in colour, smell, sound, etc. According to selectionism, brain activity does not create those relations; it only selects which of them are perceptually available to the subject on a given occasion. In effect, selectionism entails that perceptual experience is diaphanous, i.e. that sameness and difference in the phenomenal character of experience is exhausted by sameness and difference in the perceived items. It has been argued (...) that diaphaneity is undermined by phenomenological considerations and empirical evidence. This paper considers five prominent arguments of this sort and shows that none of them succeeds. (shrink)

One crucial premise in the argument from illusion is the Phenomenal Principle. It states that if there sensibly appears to be something that possesses a sensible quality, then there is something of which the subject is aware that has that sensible quality. The principle thus enables the inference from a mere appearance to an existence (usually a mental one). In the argument from appearance, a similar move is taken by some philosophers—they infer a content from a mere appearance. There are (...) two kinds of defences for the Phenomenal Principle in the literature, namely, the epistemological one (e.g. H.H. Price) and the semantic one (e.g. Frank Jackson). I argue that neither consolidates the Phenomenal Principle. I particularly demonstrate that the appearance verb in premise 1 of the argument from illusion is not used in the phenomenal sense as it is used in the Phenomenal Principle, which renders the argument essentially invalid. To avoid invalidity, the proponents either give up the phenomenal use, which makes the argument unable to serve its original purpose, i.e. inferring an unusual existence, or they insist on the phenomenal use in all premises of the argument, which will trivialise the argument. I also demonstrate that a similar objection applies to the argument from appearance. (shrink)