It is also a fact that a given mental state in one person tends to excite a like state in those with whom he associates. How important, then, that each and all cultivate, as habits, the qualities of cheerfulness, kindness, and good-will, instead of the opposite states of mind. Especially in the family, and other groups of closely associated individuals, should the nervous effect of one member upon the others be considered and every effort made to secure and maintain harmonious relations. *The High Ideal.*—Everything considered, the conditions most favorable to the healthfulness of the nervous system are in harmony with what our greatest teachers have pointed to as the higher plane of living. On this account a true conception of the value and meaning of life is of the greatest importance. _An ever present, strong desire to live a vigorous, but simple and noble, life_ will suggest the proper course to pursue when in doubt and will stimulate the power of self-control. It will lead to the stopping of "nerve leaks" and to the maintenance of harmonious relations with one’s fellows. It will cause one to recoil from the use of alcohol and other nerve poisons, as from a deadly serpent, seeing the end in the beginning, and will be the means eventually of leading the body into its greatest accomplishments. *Summary.*—The nervous system, on account of its delicate structure, is liable to injury through wrong methods of using it and also through the introduction of drugs, or poisons, into the body. There are also found in our methods of living and systems of education conditions that tend to waste the nervous energy. To protect the nervous system from all these threatened dangers requires, among other things, the power of self-control. This enables the individual to direct his life according to his highest ideals and to free himself from habits known to be injurious. Children must have their nervous systems safeguarded by parents and teachers. Especially must they be kept from becoming enslaved to some drug, such as alcohol or the nicotine of tobacco. *Exercises.*—1. In what respect is the hygiene of the nervous system the hygiene of the entire body? 2. Of what value in the hygiene of the nervous system is the power of self-control? How is the habit of self-control formed? 3. Name several forms of activity that waste the nervous energy. 4. Name several influences that react unfavorably on the nervous systems of children. 5. How may too much reading prove injurious to the nervous system? 6. What forms of physical exercise are beneficial to the brain worker? 7. Why is the use of alcohol even in small quantities to be regarded as a dangerous practice? 8. Name several causes of nervousness. 9. What are the unanswerable arguments for preventing the use of tobacco by the young? 10. Why do cigarettes have a more harmful effect upon the body than other forms of tobacco?