destroy the capacity for it" – and "enacts what 'Attacks on Linking' identifies as hatred of emotion, hatred of reality, hatred of life itself." Looking for the source of such hate (H), Bion notes in Learning from Experience that, "Inevitably one wonders at various points in the investigation why such a phenomenon as that represented by −K should exist. ... I shall consider one factor only – Envy. By this term I mean the phenomenon described by Melanie Klein in Envy and Gratitude" (1962, p. 96). Reversible perspective and −K "Reversible Perspective" was a term coined by Bion to illuminate "a peculiar and deadly form of analytic impasse which defends against psychic pain". It represents the clash of "two independently experienced views or phenomena whose meanings are incompatible". In Bion's own words, "Reversible perspective is evidence of pain; the patient reverses perspective so as to make a dynamic situation static." As summarised by Etchegoyen, "Reversible perspective is an extreme case of rigidity of thought. ... As Bion says, what is most characteristic in such cases is the manifest accord and the latent discord." In clinical contexts, what may happen is that the analyst's "interpretation is accepted, but the premises have been rejected ... the actual specificity, the substance of the interpretation". Reversible perspective is an aspect of "the potential destruction and deformation of knowledge" – one of the attacks on linking of −K. O: The ineffable As his thought continued to develop, Bion came to use Negative Capability and the suspension of Memory and Desire in his work as an analyst, in order to investigate psychic reality - which he regarded as essentially 'non-sensuous' (1970). Following his 1965 book Transformations he had an increasing interest in what he termed the domain of "O" – the unknowable, or ultimate Truth. "In aesthetics, Bion has been described as a neo-Kantian for whom reality, or the thing-in-itself (O), cannot be known, only be "be-ed" (1965). What can be known is said by Bion to be in the realm of K, impinging through its sensory channels. If the observer can desist from "irritably reaching for fact and reason", and suspend the normal operation of the faculties of memory and apperception, what Bion called transformations in knowledge can permit an 'evolution' where transformations in K touch on transformations in Being (O). Bion believed such moments to feel both ominous and turbulent, threatening a loss of