Necessity in any other use is metaphysical or philosophical necessity, and is applied out of the sphere of the will: as the necessity of truth, the necessity of being,—the necessary connexion of cause and effect. Hence,
The connexion between volitions or choices, or the sense of the most agreeable with the motive or cause, is necessary with a philosophical necessity. The necessity of volitions in reference to motives is also called moral necessity. This term moral is given, not in reference to the nature of the connexion, but in reference to the terms connected. Volitions belonging to responsible and moral beings are thus distinguished from those phenomena which we commonly call natural.
XI. An agent is that which produces effects. A natural agent is that which produces effects without volition. A moral agent is one producing effects by volitions, accompanied with an intellectual perception of the volitions and their effects, as right or wrong, and a sense of desert, or of praiseworthiness, or blameworthiness, on account of the volitions and their effects.
Brutes or irresponsible beings are agents that have volitions, but have no reason to perceive right and wrong, and consequently have no sense of desert; and as they cannot perceive right and wrong, they cannot be made the subjects of moral appeals and inducements.
XII. Moral responsibility arises first, from the possession of reason; secondly, from the capacity of choice; thirdly, from natural ability.
Natural ability exists when the effect or act commanded to be accomplished has an established connexion with volition or choice. Thus we say a man has natural ability to walk, because if he chooses to walk, he walks. Natural ability differs from freedom only in this:—The first refers to an established connexion between volitions and effects. The second refers to an absence of all impediment, or of all resisting forces from between volitions and effects.
Hence a man is naturally unable to do anything when there is no established connexion between volition and that thing. A man is naturally unable to push a mountain from its seat. He has no liberty to move his arm when it is bound.
Moral inability is metaphysical or philosophical inability. Philosophical inability in general refers to the impossibility of a certain effect for the want of a cause, or an adequate cause. Thus there is a philosophical inability of transmuting metal; or of restoring the decay of old age to the freshness and vigour of youth, because we have no cause by which such effects can be produced. There is a philosophical inability also, to pry up a rock of a hundred tons weight with a pine lath, and by the hand of a single man, because we have not an adequate cause. Moral inability relates to the connexion between motives and volitions in distinction from natural ability, which relates to the connexion between volitions and actions consequent upon them: but the term moral as we have seen, does not characterize the nature of the connexion,—it only expresses the quality of terms connected. Hence moral inability, as philosophical inability, is the impossibility of a certain volition or choice for the want of a motive or cause, or an adequate motive. Thus there is a moral philosophical inability of Paul denying Jesus Christ, for there is plainly no motive or cause to produce a volition to such an act. There is a moral philosophical inability also, of a man selling an estate for fifty dollars which is worth fifty thousand, because the motive is not adequate to produce a volition to such an act.
Philosophical necessity and inability are absolute in respect of us, because beyond the sphere of our volition.
XIII. Praiseworthiness or virtue, blameworthiness or guilt, apply only to volitions. This indeed is not formally brought out in the part of Edwards’s work we have been examining. His discussion of it will be found in part IV. sec. I. But as it is necessary to a complete view of his system, we introduce it here.