Merleau-Ponty’s Sorbonne lectures of 1949 to 1952 are a broad investigation into child psychology, psychoanalysis, pedagogy, phenomenology, sociology, and anthropology. They argue that the subject of child psychology is critical for any philosophical attempt to understand individual and intersubjective existence. Talia Welsh’s new translation provides Merleau-Ponty’s complete lectures on the seminal engagement of phenomenology and psychology.