Jacques Lacan was a French psychoanalyst and psychiatrist, known for his reinterpretation of Freudian concepts through the lens of language and structuralism. His work emphasized the role of the unconscious as structured like a language, suggesting that our identities and desires are shaped by linguistic constructs and social interactions. Lacan's ideas have had a profound influence on literary criticism by linking psychoanalysis with the study of texts and their meanings.