Any form of belief in mental healing, other than (1) Christian Science and (2) hypnotism or psychotherapy. It was practised in the 19th century, and its central principle was affirmative thought, or suggestion, employed with the conviction that man produces changes in his health, his finances, and his life by the adoption of a favorable mental attitude. As a therapeutic doctrine it stands for silent and absent mental treatment, and the theory that all diseases are mental in origin. As a cult it has its unifying idea the inculcation of workable optimism in contrast with the “old thought” of sin, evil, predestination, and pessimistic resignation. The term is essentially synonymous with the term High Thought, used in England.  [Webster 1913 Suppl.]