send it in the direction you wish it to go, and hold it there until it has discerned the object, examined the face, or found the meaning. Compel it to obey, make it work, keep it active when on duty, but give it frequent periods of rest. The only way to build up the mental faculties is by using them, but care must be exercised to make this use judicious, because it is easier to tear down than it is to build up, and many memories are ruined through being abused or overworked; therefore, the mental powers should not be taxed beyond their strength; they should not be compelled to work until they are tired out, but should be rested frequently.
The mind should not be burdened with a mass of words. The brain can only hold a certain amount, and unless matters that are not to be used immediately are stowed away in the
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