William Walker Atkinson 
Self-Healing by the Power of Thought (translated) [EPUB ebook] 

From the first chapter: “In addressing the question of Self-Healing I should first say that for me all the various methods of healing by the power of the mind are but different forms of applying the same force. I think the various practitioners of Suggestion Therapy, Mind Science, Christian Science, Faith Healing and all the rest are using the same great force, the only difference being in the method of application.”