ABSTRACT
It is in the psychoses that one encounters the most extreme rigidities and fluctuations of symptoms. This chapter reviews some aspects of S. Freud's thought in order to convey just how central a subject psychosis is to his understanding of psychic life. He wrote about the psychic life of individuals one might "classify" as hysteric, depressive, paranoid, or schizophrenic. For him, psychosis represents a more extreme, fundamental dominance of the pleasure principle, primary process thinking, and the id than neurosis represents. Freud writes, The problem of psychoses would be simple and perspicuous if the ego's detachment from reality could be carried through completely. Although he did not deny a possible physical basis for mental illness, he noted that a physicalistic bias could obscure ignorance and act as a resistance to discovering dynamic psychological events. If psychology studies mental processes, epistemology investigates what claims these processes make about the nature of reality or truth.
