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.