In From Sign to Symbol: Transformational Processes in Psychoanalysis, Psychotherapy, and Psychology, Joseph Newirth describes the evolution of the unconscious from the psychoanalytic concept that reflected Freud's positivist focus on symptoms and repressed memories to the contemporary structure that uses symbols and metaphors to create meaning within intimate, intersubjective relationships. Newirth integrates psychoanalytic theory with cognitive, developmental, and neuropsychological theories, and he differentiates two broad therapeutic strategies: an asymmetrical strategy that utilizes the logic of consciousness and emphasizes the differentiation of person, place, time, and causality in the world of objects, and a symmetrical strategy that utilizes the logic of the unconscious in the world of emotional, intersubjective experience. He presents multiple approaches to the use of these symmetrical therapeutic strategies, including the use of humor, dreams, metaphors, and implicit procedural learning, in transforming concrete symptoms and signs into the symbolic organizations of meaning. Examples from both psychotherapeutic practice and supervision are presented to illustrate the development of the capacity for symbolic thought or mentalization.