"Try to describe the aroma of Colombian coffee": Grice on synaesthesia

Witters, wanting to sound funny or cryptic, or challenging wrote (well Anscombe did):

Try to describe the aroma of coffee.

The implicature was "and fail".

But not so.

The problem, Grice notes, "is not really Wittgenstein's, but Molyneux".

If we define a range of phi-epithets as falling within one of the recognised five senses (Grice left the common sense out as otiose), we have

'big'

can apply to things we _touch_ and things we _see_. Hardly to things we _smell_.

"A big smell" sounds _harsh_, Grice comments.

"It all depends on your addressee. It may not sound harsh to them poetic types as love a synaesthesia", he was ready to grant. Etc.