"This book has been written in the hope of alleviating, in some part, such burdens and to give some guidance in the re-education of control. It is primarily the fruit of the author's own personal experience. In the first place it is meant for those who are fatigued from excessive work, worries, or sufferings. Possibly they may have lost control of their thoughts and so will not know how to rest or sleep peacefully; or they may be unable to control their fears or sadness. The first part of the book is intended especially for this group. Secondly, we are writing for those who are healthy of mind but who wish greater efficiency in studies or business, greater energy and constancy in carrying out plans, greater control of feelings or instincts, more joy, satisfaction, and interior happiness. These will find useful and practical advice especially in the second part of the book. Further, we are also writing for educators and directors of souls who meet up with problem cases regarding study or vir- tue. These problems often arise because of mental wandering, inefficiency, indecision, or even laziness of will. Difficulties may also come from uncontrolled passions, unreasonable fears, or feelings of inferiority. In the arrangement of the book our purpose is first of all to be practical, to make it easier for you, our readers, to get quick control of your nervous and mental energies. The upshot of this will be greater efficiency in work and greater mental health. We want also to be accessible, even for non- specialists, in order to lessen mental sufferings and help those who need orientation or advice in their work or studies. We want, too, to save time for you. Hence we unify our teachings, condense explanations, make résumés of them, and include outline diagrams or charts at the end of each chapter. We want, further, to focus your attention especially on mental fatigue, mental weakness, insufficient control, and the inter- nal difficulties which these cause. In practical applications we limit ourselves to the more immediate results of acquired control. And, finally, we want to interweave aphorisms or maxims which are educative and healthily optimistic. Once you engrave these on your mind by repetition, they will help to increase your health, efficiency, and happiness"--