The term 'Freud Subjects' refers to the psychological theories of Sigmund Freud, which focused on the unconscious mind and its influence on behavior. The four-letter solution to this crossword is 'egos, ' which refers to Freud's concept of the ego, or the conscious part of the mind that mediates between the demands of the id (the unconscious) and the superego (the conscience). The ego is responsible for making decisions and forming judgments based on reality.