and not as a common conviction (sententia communis). These questions have been discussed at great length by Moral Theologians in the controversy on Probabilism. See Lacroix, Theol. Mor., lib. I., tr. i., c. 2.
The consent of Theologians produces certainty that a doctrine is Catholic truth only when on the one hand the doctrine is proposed as absolutely certain, and on the other hand the consent is universal and constant (Consensus universalis et constans non solum opinionis sed firmæ et ratæ sententiæ). If all agree that a particular doctrine is a Catholic dogma and that to deny it is heresy, then that doctrine is certainly a dogma. If they agree that a doctrine cannot be denied without injuring Catholic truth, and that such denial is deserving of censure, this again is a sure proof that the doctrine is in some way a Catholic doctrine. If, again, they agree in declaring that a doctrine is sufficiently certain and demonstrated, their consent is not indeed a formal proof of the Catholic character of the doctrine, nevertheless the existence of the consent shows that the doctrine belongs to the mind of the Church (catholicus intellectus), and that consequently its denial would incur the censure of rashness.
These principles on the authority of Theologians were strongly insisted on by Pius IX. in the brief, Gravissimas inter (cf. infra, § 29), and they are evident consequences of the Catholic doctrine of Tradition. Although the assistance of the Holy Ghost is not directly promised to Theologians, nevertheless the assistance promised to the Church requires that He should prevent them as a body from falling into error; otherwise the Faithful who follow them would all be led astray. The consent of Theologians implies the consent of the Episcopate, according to St. Augustine’s dictum: “Not to resist an error is to approve of it—not to defend a truth is to reject it.” And even natural reason assures us that this consent is a guarantee of truth. “Whatever is found to be one and the same among many persons is not an error but a tradition” (Tertullian). (Supra, p. 68.)
