Biological diversity is presented as a model of psychic diversity. Perversity, the general form of perversion which pervades, to some extent, the psyches of us all, is not presented as a diversity of lifestyle, as political correct-ness might have it. It is presented as a psychopathology causing suffering and needing help. The reprehension of perversity is suggested, through the work of Bion, as itself an aspect of perversity. The difficulties of analysing perversity through the general condition of narcissism is addressed emotionally through the universality of some measure of narcissism and theoretically through the work of Bion on ‘without-ness’, frustration and the disappointment of constant conjunction, and through Meltzer's distinction between polymorphous and perverse and through his concept of aesthetic conflict.