In the most widely different states of life in the Church he sees virtue grow in the degree in which one submits to her guidance. He witnesses the remarkable spectacle, that everything noble and good is attracted by the Church, and their contrary repelled. He sees the miracles which never cease in her midst. Finally he beholds her admirable unity and vigorous faith; she alone holding firm to her teaching, not compromising with any error; she alone holding fearlessly aloft the principle of divine authority, and thus becoming a beacon to many who are seeking a safe shelter from spiritual ruin. In addition we finally have that harmony and grandeur of the truths of faith, and—perhaps not in the last place—that calm and peace of mind, produced in the faithful soul by a life led according to this faith, by prayer and the reception of the Sacraments. This is a clear proof that where the Spirit of God breathes there cannot be the seat of untruth. These are sufficient proofs to produce even in the uneducated, and in children, true and reasonable certainty, provided they have had sufficient instruction in religion. It must, however, be emphasized that this conviction produced by faith need _not first be gained by scientific investigation_ of the motives of faith, or by minute or extensive theological studies. A wrong notion of human knowledge frequently leads to the opinion that there is no true certainty at all unless it is the result of scientific study—a presumption on which is based the claim of freedom of science to disregard any conviction, be it ever so sacred, and the claim that it is reserved to science alone to attain the sure possession of the truth. Later on we shall dwell more at length upon this important point. Let it suffice here to remark that the intellect can attain real certainty even without scientific research; most of our convictions, which we all hold unhesitatingly as true, are of this kind. They constitute a belief that is based upon the real knowledge of the reason, which knowledge is not, however, so clear and distinct that it could be demonstrated easily in scientific form. The certainty of faith, therefore, is based upon the knowledge that God Himself vouches for the truth of the teachings of faith. This relieves the faithful from the necessity of obtaining by his own reflection an insight into the intrinsic reasons of the why and the wherefore of the proposed truth, and to examine in each instance the correctness of the thing. He knows that God has revealed it, that His infallible Church vouches for it; hence it is credible and true; that suffices for him, just as trustworthy evidence suffices for the historian concerning facts which he himself has not observed.