The human faculties of perception, judgment, discriminative feeling, mental activity, and even moral preference, are exercised only in making a choice. He who does anything because it is the custom, makes no choice. He gains no practice either in discerning or in desiring what is best. The mental and moral, like the muscular powers, are improved only by being used. The faculties are called into no exercise by doing a thing merely because others do it, no more than by believing a thing only because others believe it. If the grounds of an opinion are not conclusive to the person’s own reason, his reason cannot be strengthened, but is likely to be weakened by his adopting it: and if the inducements to an act are not such as are consentaneous to his own feelings and character (where affection, or the rights of others are not concerned), it is so much done towards rendering his feelings and character inert and torpid, instead of active and energetic.
He who lets the world, or his own portion of it, choose his plan of life for him, has no need of any other faculty than the ape-like one of imitation. He who chooses his plan for himself, employs all his faculties. He must use observation to see, reasoning and judgment to foresee, activity to gather materials for decision, discrimination to decide, and when he has decided, firmness and self-control to hold to his deliberate decision.