With the records of my casebooks for over twenty years before me I feel it right to set down my convictions in terms that do not admit of any doubt or uncertainty. My conclusions upon the urgent question of physical decadence have not been formulated in haste. They are deductions from a long series of striking results and observed facts, and, frankly, I consider them so important that I cannot hesitate to deliver my message in a tone which may appear to some to savour of over-confidence. So be it! I SYNOPSIS OF CLAIM 1. My first claim is that psycho-physical guidance by conscious control, when applied as a universal principle to “living,” constitutes an unfailing preventive for diseases mental or physical, malformations, and loss of general efficiency. It is commonly considered that these conditions are brought about by such evils of civilisation as the limitation of energy, and by that loss of so-called “natural conditions” which civilisation entails. It is my earnest belief that the intelligent recognition of the principles essential to guidance by conscious control are essential to the full mental and physical development of the human race. Due consideration will convince even the sceptical that if mankind is to evolve to the higher stages of mental and physical perfection, he must be guided by these principles. They alone will bring men and women of to-day to the highest state of well-being, enabling them to grapple effectively with the problems of the day in the world of thought and action, gradually widening the dividing line which separates civilised mankind from the animal kingdom. There is no sphere of human activity, of human feeling or philosophy where the adoption of the principles of conscious guidance and control would not bring invaluable benefits. At present man is held in bondage by many subconscious instincts which enslave the animal kingdom, the savage, and the semi-savage. Let me illustrate this. Animals and savages become immediately unbalanced when they experience the unusual, as for instance, when they see an express train dash along for the first time. Such a new experience would cause the bravest animal to become overwhelmed with that degree of fear which momentarily suspends his normal guidance by instinct. So also with the savage, who would be equally unbalanced by an experience of this kind. In most spheres of normal life, he, like the animal, depends on instinctive guiding principles which act with perfect balance under accustomed circumstances. In the face of the unusual, however, he is unable to meet suddenly the requirements of a new environment. To meet these he needs reasoned, conscious guidance which is the outcome of the habit of conscious control, and marks the dividing line between the animal kingdom, where instinct is the guide, and the human kingdom where its members are in communication with reason.