Argument:
\begin{enumerate}
\item Red things differ in visual appearance from non-red things.
\item The capacity to detect the difference in visual appearance between
red and non-red things is, or depends on, the capacity to visually
discriminate red and non-red things.
\item The capacity to visually discriminate red and non-red things depends
on the capacity to label the red things (for example, using ‘red’).
\end{enumerate}
Therefore:
\begin{enumerate}[resume]
\item I have a perceptual experience as of red span.italic
because span I call the perceived object ‘red’.
\end{enumerate}
1. Red things differ in visual appearance from non-red things.
[assumption]
2. The capacity to detect the difference in visual appearance between
red and non-red things
is, or depends on,
the capacity to visually discriminate red and non-red things.
[unargued premise]
3. The capacity to visually discriminate red and non-red things
depends on
the capacity to label the red things (for example, using ‘red’).
[discovery]
It turns out that
the ability to discriminate properties denoted by particular colour terms like
‘red’ depends not only on having learned to use those very terms accurately in
the past \citep{Ozgen:2002yk,Winawer:2007im,zhou:2010_newly} but also on being
able to activate some component of the ability to apply the colour term at the
time a stimulus is presented
\citep{Roberson:2000ge,Pilling:2003bi,Wiggett:2008xt}. % page refs: (Roberson,
Davies and Davidoff 2000: 985; Pilling, Wiggett, et al. 2003: 549-50; Wiggett
and Davies 2008)
Someone who accepts that there are visual experiences as of
\emph{red} must either suppose that these experiences are only indirectly
related to abilities to discriminate or else accept the surprising idea that
such visual experiences are a consequence of covert labelling. This dilemma can
be avoided by rejecting the subject-determining platitude and with it the
existence in humans of visual experiences as of \emph{red}.
Therefore:
4. I have a perceptual experience as of red because I call the perceived object ‘red’.
Should we reject this ...