b) The relation between merely sufficient and efficacious grace in the Augustinian system, therefore, may be described as follows: Merely sufficient grace imparts to the will the _posse_ but not the _velle_, or at best only such a weak _velle_ that it requires the _delectatio victrix_ (_gratia efficax_) to become effective. Efficacious grace (_delectatio coelestis victrix_), on the other hand, impels the will actually to perform the good deed. Hence there is between the two an essential and specific difference, and the efficacy of that grace which leads to the performance of salutary acts does not lie with free-will but depends on the _delectatio coelestis_, which must consequently be conceived as _gratia efficax ab intrinseco sive per se_.(749) c) Nevertheless, the necessity of the _gratia efficax ab __ intrinseco_, according to the Augustinian theory, is not due to the subordination of the _causa secunda_ to the _causa prima_, as the Thomists contend, but to a constitutional weakness of human nature, consisting in this that its evil impulses can be overcome solely by the _delectatio coelestis victrix_ (_gratia efficax, adiutorium quo_. The case was different before the Fall, when the _gratia versatilis_ (_gratia sufficiens, adiutorium sine quo non_) sufficed for the performance of salutary acts.(750) d) However, the Augustinians insist against the Jansenists, that the delectatio _coelestis_ (_i.e._ efficacious grace) does not intrinsically compel the will, but acts merely as a _praemotio moralis_, and that while the will obeys the inspiration of grace infallibly (_infallibiliter_) it does not do so necessarily (_non necessario_). With equal certainty, though not necessarily, the will, when equipped solely with sufficient grace, succumbs to concupiscence. The ultimate reason for the freedom of the will is to be found in the _indifferentia iudicii_.(751) By way of exemplification the Augustinians cite the case of a well-bred man who, though physically free and able to do so, would never turn summersaults on a public thoroughfare or gouge out his own eyes. CRITICAL ESTIMATE OF AUGUSTINIANISM.—On account of its uncritical methods Augustinianism has found but few defenders and deserves notice only in so far as it claims to base its teaching on St. Augustine. Like the Bible, the writings of that holy Doctor have been quoted in support of many contradictory systems.(752) If the use of Augustinian terms guaranteed the possession of Augustinian ideas, Jansenius would have a strong claim to be considered a faithful disciple of St. Augustine. Yet how widely does not the “Augustinus Iprensis,” as he has been called, differ from the “Augustinus Hipponensis”! Augustinianism, too, utterly misconceives the terms which it employs. Space permits us to call attention to one or two points only. a) In the first place Augustinianism labors under an absolutely false conception of sufficient grace.