Geoffrey H, who had recently graduated at Cambridge, came to visit my mental hospital. After some hours he found his way to the patients' social club in which patients from all wards in the hospital congregate for organized games and dancing. Inevitably a long-stay patient approached him, and then asked the remarkable question 'Hello, are you here?' The significance of this question resides in the patients' perception of the difference between staff and patients. Patients are 'here', inside; staff are not here: they come and go but, essentially, even if they live on the hospital estate and spend most of their spare time in the staff social club, they are outsiders. One savours this question with its implicit violence to ordinary meaning: 'are you here?' One reflects on the peculiar dialectic between 'here' and 'there'. The one who is here is not all there. Reciprocally the one who is not here is one who is there, that is to say not here, that is to say non-existent in the present actual circumstances. Geoffrey told me of his impressions of a mental hospital in these terms: solid but amorphous lumps of patients drifting around the grounds, gesturing, gesticulating, reviling, appealing - to thin air; shadowy imprints of staff engaged, if one may use so highly concrete a term, in jocular interaction or serious concerned discussion with patients and their fellow-staff: this man slaps another on his back but the back is not there, nor is the hand.