But it is not true that control of the thoughts is impossible. Thoughts are the result of the action of the brain; and the action of the brain may be controlled as well as the movements of a voluntary muscle. It may be more difficult, especially when the resolution is weakened, as it is by this vice; but so long as there are left any remnants of will and reason, control is possible. To strengthen the will must be one of the objects of mental treatment, and exercise is the method by which it may be accomplished. The thing for a sufferer to say, is not, "I can't," but, "I can and I will control my thoughts." Suggestions which will aid in accomplishing this have already been given under the heading, "Cure of the Habit." We cannot forbear to add a word further respecting the worth of religion in aiding these sufferers. If there is any living creature who needs the help of true religion, of faith in God, in Christ, and in the efficacy of prayer, it is one of these. If there is any poor mortal who can not afford to be deprived of the aid of a sympathizing Saviour, it is one who has enervated his will, degraded his soul, and depraved his body by the vile habit of self-abuse. A compassionate Redeemer will succor even these defiled ones, if they truly "hunger and thirst" after purity, and if they set about the work of reforming themselves in good earnest, and with right motives. Exercise.--Physical exercise is a most powerful aid to pure thoughts. When unchaste ideas intrude, engage at once in something which will demand energetic muscular exercise. Pursue the effort until fatigued, if necessary, making, all the while, a powerful mental effort to control the mind. Of course, evil thoughts will not be expelled by thinking of them, but by displacing them by pure thoughts. Exercise aids this greatly. Exercise is also essential to balance the circulation, and thus relieve congestion of internal organs. Sedentary persons especially need systematic exercise. No single form of exercise is so excellent as walking. Four or five miles a day are none too many to secure a proper amount of muscular exercise. Gymnastics, the "health-lift," "Indian clubs," "dumb-bells," rowing, and other forms of exercise are all good; but none of them should be carried to excess. Ball-playing is likely to be made a source of injury by exciting, in vigorous competition, too violent and spasmodic action. Daily exercise should be taken to the extent of fatigue. It is better that those who are still strong enough should have some regular employment which will secure exercise. Those who prefer may secure exercise and recreation in the pursuit of some study that involves necessary physical exertion; as, botany, geology, or entomology. The collection of natural-history specimens is one of the most pleasant diversions, and may be made very useful as well.