'Always look on the bright side of life' is of course no cure-all at all.
The Coué method
The application of a mantra-like conscious autosuggestion, "Every day, in every way, I'm getting better and better" (French: Tous les jours à tous points de vue je vais de mieux en mieux) is called Couéism or the Coué method. The Coué method centres on a routine repetition of this particular expression according to a specified ritual, in a given physical state, and in the absence of any sort of allied mental imagery, at the beginning and at the end of each day.
Unlike the common once held belief that a strong conscious will constitutes the best path to success, Coué maintained that curing a person's troubles requires a change in unconscious thought, which can only be achieved by using the imagination. Although stressing that he was not primarily a healer but one who taught others to heal themselves, Coué claimed to have effected organic changes through autosuggestion.
Coué noticed that in certain cases he could improve the efficacy of a given medicine by praising its effectiveness to the patient. He realized that those patients to whom he praised the medicine had a noticeable improvement when compared to patients to whom he said nothing. This began Coué’s exploration of the use of hypnosis and the power of the imagination.
His initial method for treating patients relied on hypnosis. He discovered that subjects could not be hypnotized against their will and, more importantly, that the effects of hypnosis waned when the subjects regained consciousness.
Hence he eventually turned to autosuggestion, which he describes as
" an instrument that we possess at birth, and with which we play unconsciously all our life, as a baby plays with its rattle. It is however a dangerous instrument; it can wound or even kill you if you handle it imprudently and unconsciously. It can on the contrary save your life when you know how to employ it consciously."
Coué believed in medication. But he also believed that our mental state is able to affect and even amplify the action of certain medications. By consciously using autosuggestion, he observed that his patients could cure themselves more efficiently by replacing their "thought of illness" with a new "thought of cure". According to Coué, repeating words or images enough times causes the subconscious to absorb them. The cures were the result of using imagination or "positive autosuggestion" to the exclusion of one's own willpower.
Coué thus developed a method which relied on the principle that any idea exclusively occupying the mind turns into reality, although only to the extent that the idea is within the realm of possibility. For instance, a person without hands will not be able to make them grow back. However, if a person firmly believes that his or her asthma is disappearing, then this may actually happen, as far as the body is actually able to physically overcome or control the illness. On the other hand, thinking negatively about the illness (ex. "I am not feeling well") will encourage both mind and body to accept this thought. Likewise, when someone cannot remember a name, they will probably not be able to recall it as long as they hold onto this idea (i.e. "I can't remember") in their mind. 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").
Coué observed that the main obstacle to autosuggestion was willpower. 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. Everything must thus be done to ensure that the positive "autosuggestive" idea is consciously accepted by the patient, otherwise one may end up getting the opposite effect of what is desired.
For example, when a student has forgotten the answer to a question in an exam, he will likely think something such as "I have forgotten the answer". The more he or she tries to think of it, the more the answer becomes blurred and obscured. However, if this negative thought is replaced with a more positive one ("No need to worry, it will come back to me"), the chances that the student will come to 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. When he instructed a child by saying "clasp your hands and you can't open them", the child would thus immediately follow.
A patient's problems are likely to increase when his willpower and imagination are opposing each other, something Coué referred to as "self-conflict". In the student's case, the will to succeed is clearly incompatible with his thought of being incapable of remembering his answers. As the conflict intensifies, so does the problem: the more the patient tries to sleep, the more he becomes awake. The more a patient tries to stop smoking, the more he smokes. The patient must thus abandon his willpower and instead put more focus on his imaginative power in order to fully succeed with his cure.
This is an extract from Wikipedia's Coue article.
The fact is the twice daily repeating of the mantra has been the catalyst to turn those afflicted around onto a brighter path. When self-belief begins to make inroads on a sense of hopelessness people do find their natural enthusiasms and interest in the all the positive fascinating things life has to offer come back.
People do find inspiration in memorable phrases spoken or written in extremis or in quiet reflection. Harry Hooten's 'It's Great to be Alive' was written just before his death from cancer, lying in hospital the morphine easing his pain.