§71

Although someone may misunderstand your definition of 'game' that does not mean that there is something unsatisfactory with the concept or that it is not a concept or that there is something wrong with ostensive definitions more generally. Any kind of explanation can be misunderstood.

There are other cases where we do not draw a sharp boundary but where what we say is 'fit for purpose' (and perhaps drawing a sharp boundary would not suit our purpose). I might go shopping with a friend and then agree to go off individually and meet up later. I could say, "let's meet outside Sainsburys at about 2pm". - I haven't specified an exact spot to meet - and it isn't even clear what specifying an exact spot would amount to (latitude-longitude coordinates which pick out a precise point? - But then where should we stand in relation to the point specified?)