The Mind Is Like An Iceberg

Sigmund Freud used the iceberg as a metaphor for the mind's structure in his lectures and writings on the unconscious, though the exact formulation with the "one-seventh" fraction is a later popularisation not found verbatim in his texts. The structural model he developed distinguishes the unconscious (the bulk of mental life, inaccessible to ordinary awareness) from the preconscious and conscious (the small portion available to reflection). Earlier he used the topographical terms id, ego, and superego in the tripartite model of the 1920s, which gradually displaced the simple conscious/unconscious opposition. The iceberg image accurately captures his core claim.