Self Mastery Through Conscious Autosuggestion

Considered at times to represent a second Nancy School, Cou treated many patients in groups and free of charge.

Life and career
Cou 's family, from the Brittany region of France and with origins in French nobility, had only modest means. A brilliant pupil in school, he initially intended to become an analytical chemist. However, he eventually abandoned these studies, as his father, who was a railroad worker, was in a precarious financial state. Cou then decided to become a pharmacist and graduated with a degree in pharmacology in 1876.

Working as an apothecary at Troyes from 1882 to 1910, Cou quickly discovered what later came to be known as the placebo effect. He became known for reassuring his clients by praising each remedy's efficiency and leaving a small positive notice with each given medication. In 1886 and 1887 he studied with Ambroise-Auguste Li beault and Hippolyte Bernheim, two leading exponents of hypnotism, in Nancy.

In 1910, Cou sold his business and retired to Nancy, where he opened a clinic that continuously delivered some 40,000 treatment-units per annum (Baudouin, 1920, p.14) to local, regional, and overseas patients over the next sixteen years. In 1913, Cou and his wife founded The Lorraine Society of Applied Psychology (French: La Soci t Lorraine de Psychologie appliqu e). His book Self-Mastery Through Conscious Autosuggestion was published in England (1920) and in the United States (1922). Although Cou 's teachings were, during his lifetime, more popular in Europe than in the United States, many Americans who adopted his ideas and methods, such as Norman Vincent Peale, Robert H. Schuller, and W. Clement Stone, became famous in their own right by spreading his words.