Children should be early taught, in simple, easy lessons, the rudiments of physiology and hygiene. The work should be begun by the mother in the home, and should be faithfully carried forward in the school. As the pupils advance in years, instruction in this line should be continued, until they are qualified to care for the house they live in. They should understand the importance of guarding against disease by preserving the vigor of every organ, and should also be taught how to deal with common diseases and accidents. Every school should give instruction in both physiology and hygiene, and, so far as possible, should be provided with facilities for illustrating the structure, use, and care of the body. [Sidenote: _Nature’s Laws Divine_] There are matters not usually included in the study of physiology that should be considered,—matters of far greater value to the student than are many of the technicalities commonly taught under this head. As the foundation principle of all education in these lines, the youth should be taught that the laws of nature are the laws of God,—as truly divine as are the precepts of the decalogue. The laws that govern our physical organism, God has written upon every nerve, muscle, and fiber of the body. Every careless or wilful violation of these laws is a sin against our Creator. How necessary, then, that a thorough knowledge of these laws should be imparted! The principles of hygiene as applied to diet, exercise, the care of children, the treatment of the sick, and many like matters, should be given much more attention than they ordinarily receive. [Sidenote: _Influence of the Mind on the Body_] The influence of the mind on the body, as well as of the body on the mind, should be emphasized. The electric power of the brain, promoted by mental activity, vitalizes the whole system, and is thus an invaluable aid in resisting disease. This should be made plain. The power of the will and the importance of self-control, both in the preservation and in the recovery of health, the depressing and even ruinous effect of anger, discontent, selfishness, or impurity, and, on the other hand, the marvelous life-giving power to be found in cheerfulness, unselfishness, gratitude, should also be shown. There is a physiological truth—truth that we need to consider—in the scripture, “A merry [rejoicing] heart doeth good like a medicine.” [Sidenote: _Cheerfulness; Gratitude_] “Let thine heart keep My commandments,” God says; “for length of days, and years of life, and peace, shall they add to thee.” “They are life unto those that find them, and health to all their flesh.” “Pleasant words” the Scriptures declare to be not only “sweet to the soul,” but “health to the bones.”[320]