All this is obvious. The plant could not exist at all did it not develop those qualities which would minister to its welfare and adjust it perfectly to its environment. But in human economy we fancy somehow that the law is less strict and more irregular, and can be violated at times with impunity. We think that a man can perform the part of a physician, and cure others, although he cannot cure a trouble that afflicts himself; that he can restore others to health while he himself is unhealthy. We can separate between a man's skill and his personality; and, indeed, there are many cases where a physician who is dying slowly of some incurable disease can yet, by his knowledge and cleverness, so treat his patients that he may heal their diseases and restore them to health and strength. But we are usually suspicious of a doctor endeavouring to cure others when he himself labours under an uncured disease. We reason naturally that his first concern should be himself; and if he fails in doing good to himself by his skill and medicine, when his interests are most of all concerned and the motive for healing strongest, how can he hope to succeed in the case of others, strangers and comparatively indifferent to him? We should not accept with implicit confidence a so-called remedy for baldness forced upon our notice by a person whose own head was in that condition. We should expect him to operate upon himself in the first instance with success, and then we should feel disposed to venture upon a similar use of it. The proverb says that "He who drives fat cattle must himself be fat"; and upon the principle involved in that common saying he who would heal others must himself be a specimen of that active, vigorous health to which he wishes to restore others. In no work, indeed, is the personal equation of more consequence than in the work of the physician. Three-fourths of the elements that enter into all diseases are spiritual, and three-fourths of the remedies that must be used for them must also be spiritual. The personal appearance, character, and manner of the physician himself are most important factors in the cure of disease. Confidence in the doctor is more than half the cure; and therefore what the doctor is in himself is of great consequence. In the spiritual sphere the physician can only heal others as he heals himself. He himself must be an exemplification of the saving health of God's countenance if he is to do good to others. It is just as true in the affairs of the human soul as it is in the case of the plant--that the quality which is beneficial to the soul itself is equally beneficial to the world. It is noticeable, however, that there are exceptions to the rule in the spiritual world as there are exceptions in the natural human world. Just as there are cases of physicians healing bodily diseases in others while their own disease is unhealed, so there are cases where a man is the means of saving others while he himself is unsaved.