[1][2] Coué's method was based upon the view that, operating deep below our conscious awareness, a complex arrangement of 'ideas', especially when those ideas are dominant,[6] continuously and spontaneously suggest things to us; and, from this, significantly influence one's overall health and wellbeing.

In 1910, Coué 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.

Although Coué'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 Elsie Lincoln Benedict, Maxwell Maltz, Napoleon Hill, Norman Vincent Peale, Robert H. Schuller, and W. Clement Stone, became famous in their own right by spreading his words.

Considered by Charles Baudouin to represent a second Nancy School,[10][11] Coué treated many patients in groups and free of charge.

"[16] Unlike a commonly held belief that a strong conscious will constitutes the best path to success, Coué maintained that curing some of our troubles requires a change in our unconscious thought, which can be achieved only by using our imagination.

[14] Coué identified two types of self-suggestion: (i) the intentional, "reflective suggestion" made by deliberate and conscious effort, and (ii) the involuntary "spontaneous suggestion", that is a "natural phenomenon of our mental life … which takes place without conscious effort [and has its effect] with an intensity proportional to the keenness of [our] attention".

[17] Baudouin identified three different sources of spontaneous suggestion: According to Yeates, Coué shared the theoretical position that Thomson Jay Hudson had expressed in his Law of Psychic Phenomena (1893): namely, that our "mental organization" was such that it seemed as if we had "two minds, each endowed with separate and distinct attributes and powers; [with] each capable, under certain conditions, of independent action".

[20] Coué ... had been operating a free clinic at his home in Nancy, France, [since 1910] where he used the psychological technique of non-hypnotic suggestion as group treatment, not only for the supposed mental and physical healing of his patients, but also for enabling them to improve their character and to attain a confident self mastery.

While Coué did not denigrate the conscious self and reason, he certainly diminished its role, likening it to a little island on the vast ocean of the unconscious.

Coué realised that it is better to focus on and imagine the desired, positive results (i.e., "I feel healthy and energetic," and "I can remember clearly").

[22] For the method to work, the patient must refrain from making any independent judgment, meaning that he must not let his will impose its own views on positive ideas.

However, if this negative thought is replaced with a positive one ("No need to worry - it will come back to me"), the chances that the student will remember the answer will increase.

Coué noted that young children always applied his method perfectly, as they lacked the willpower that remained present among adults.

The list of ailments included kidney problems, diabetes, memory loss, stammering, weakness, atrophy, and all sorts of physical and mental illnesses.

[25] Some critics, such as Barrucand and Paille (1986), argue that the astonishing results widely attributed to Coué were due to his charisma, rather than his method.

[30] According to Yeates (2016a, p. 19), the protests routinely made by those within the psychomedical establishment (e.g., Moxon, 1923; Abraham, 1926) were on one or more of the following grounds: While most American reporters of his day seemed dazzled by Coué's accomplishments,[31][32][33] and did not question the results attributed to his method,[34] a handful of journalists and a few educators were skeptical.

The bust was stored for safe-keeping during World War II[citation needed] and, postwar, in 1947, was restored to its former position through the efforts of Armand Lebrun, the director of the Institut Coué in Brussels from 1923.