Émile Coué de la Châtaigneraie (French: [emil kue d? la ??t????]; 26 February 1857 – 2 July 1926) was a French psychologist and pharmacist who introduced a popular method of psychotherapy and self-improvement based on optimistic autosuggestion.Considered by Charles Baudouin to represent a second Nancy School, Coué treated many patients in groups and free of charge.