Before defining the ego explicitly, Freud argues for a manner in which unconscious thoughts can be made conscious. He believes the answer lies in the difference between unconscious thoughts and preconscious thoughts: The unconscious are "worked out upon some sort of material that remains unrecognized" (21), while the preconscious are connected to perceptions, especially "verbal images". The difference, then, is a connection to words (more specifically, to the "memory residue" of words.) The goal of psychoanalysis, then, is to connect the freely floating unconscious material to words via psychoanalytic dialogue.