The mind may be exercised with comparative safety if the physical powers are equally taxed—The mind is not to be constantly taxed to the neglect of the physical powers. The ignorance of physiology, and a neglect to observe the laws of health, have brought many to the grave who might have lived to labor and study intelligently. The proper exercise of mind and body will develop and strengthen all the powers. Both mind and body will be preserved, and will be capable of doing a variety of work. Ministers and teachers need to learn in regard to these things, and they need to practice as well. The proper use of their physical strength, as well as of the mental powers, will equalize the circulation of the blood, and keep every organ of the living machinery in running order. Minds are often abused; they are goaded on to madness by pursuing one line of thought; the excessive employment of the brain power and the neglect of the physical organs create a diseased condition of things in the system. Every faculty of the mind may be exercised with comparative safety if the physical powers are equally taxed, and the subject of thought varied. We need a change of employment, and nature is a living, healthful teacher.—Life Sketches of Ellen G. White, 353, 354. PaM 72.3