Someone asked offlist what I meant by "Gricean implicature". It's a term of art, and a theoretical construct of some generality and significance, in the theory of discourse. Have a look at, e.g. (plucked fairly randomly from some Googled sites): http://www.isc.cnrs.fr/noveck.htm http://mh.cla.umn.edu/grice.html etc etc. Damien