I used to go to a slow-open group about once a week. The number of group members varied. I realised how important the others were one Sunday afternoon when I was the first one there, and for a while I stood and waited and watched the smooth undisturbed water, so clear that I could see through it and imagine that I was about to dive into a huge blue room. For a moment it was as if the very emptiness and silence had made the water disappear, as if only the activity of other people could make it visible and real enough for me to be able to drop into it and find my way across to the other side. On quiet days, the one or two other people who are there engaged in strange disconnected elements of activity, make stark echoes against the glass roof, but the splashing, which makes the water real, still serves to accentuate the bareness of the place. Then we studiously avoid each other and deliberately display the way we swim as being a solitary enclosed activity that needs let no one else into our space. It is only when the numbers get up to about nine or ten that the swimming pool really turns into a wet group.

This wet group could be a small group, sometimes turning into what might be termed a ‘median’ group (that is, what group analysts call a medium-sized group) – but usually no more than this for me when I have my contact lenses in.