A proposition has intension (meaning) and extension (referent). All that can be demonstrated
is extension. Thus, the private language argument. etc ......http://consc.net/papers/intension.html
In the case of - for example - so called body language
, this is instincltive behaviour, which exactly makes the point. Babies know to cry when hungry of hurting, but the rest is learned
The idea there's an accessible mental state - and that mine is like yours - is supposition, and one Wittgenstein suggests is useless, since a language can only defined in public
For example, as to what the word red means
. there's no possible way
of comparing your
"private mental sensation of red" with mine
"The point is.. that language (speaking out loud) does not have to be comprehendable to get a message across effectively".
No. "Getting a message across" is saying that "one behaviour causes another behaviour", but that's just psychology, nothing to do with meaning!