The classical theory of dream function takes for granted an ego capable of adequate repression and of performing the psychic work of dreaming, which implies a certain amount of working through of internal problems. It also takes for granted the capacity for symbolisation. In Melanie Klein view, symbolisation occurs by a repression and displacement of interest in the mother's body so that objects in the external world are endowed with symbolic meaning. Wilfred Ruprecht Bion reports on a patient who was terrified by the appearance of his analyst in the dream, as he took it as evidence of having actually devoured the analyst. Bion distinguishes between alpha and beta elements of mental functioning. Beta elements are transformed into alpha elements by the alpha function. The infant deals with discomfort and anxiety by projecting it into mother. This is not only a phantasy operation. A good enough mother responds to the infant's anxiety.