From a psychoanalytical point of view, "unconscious proper" must be reserved for material that can not gain any access to becoming conscious.Of all the fundamental concepts which we owe to Freud's genius, none more clearly marks his discovery than the concept of psychic reality.The reality of the unconscious contents of mind, the structural "Unconscious", creates in the mind illusory belief.It derives from a hallucinatory activity issued from the Id which imposes itself on the Ego as reality. The Ego must believe in reality of unconscious fantasy as he believes in the external world.The analyst's understanding results from the associative work that he experiences with the patient. The term "co-thinking" is suggested for linking patient and analyst through this emerging process. "— End of Abstract'