A well-known difficulty arises from this chapter. If pure spirits and disembodied souls, for there is question of both here, have a natural desire of seeing the substance, essence, or what Holy Writ calls the face of God, which sight is called by theologians the 'beatific vision'; and this natural desire of the beatific vision points to a corresponding possibility of realisation; then either this vision can be attained by natural means, a piece of ultra-Pelagianism which St Thomas is the first to repudiate (Chapp. LII, LIII); or men and angels, as such, require to be raised to the supernatural state, and could never possibly have been left by God to the mere intrinsic powers of their nature, a position virtually Pelagian, as making grace a requisite of nature, -- a position formally condemned by the Church in Baius (Michael Le Bay of Louvain) and Jansenius, and rejected by all modern Catholic theologians, who insist on the absolute possibility of what they call a 'state of pure (mere) nature.' Three Popes, in 1567, 1579, 1641, condemned this proposition of Baius: "It is an opinion excogitated by vain and otiose men, according to the folly of philosophers, that man in his first origin was the recipient of gifts superadded to his nature, and so was elevated by the divine bounty and adopted to be a son of God." Baius meant that these gifts of adoption and sonship were proper to human nature. Again this saying of Quesnel is condemned in the Bull Unigenitus of 1713: "The grace of God is a consequence of nature, and was due to nature sound and whole." This matter is lucidly explained in Father Harper's Peace through the Truth, First Series, pp. 293-296. I have written upon the subject, Ethics and Natural Law, pp. 21-25; Oxford and Cambridge Conferences, First Series, pp. 211--217, 253-257.
But how deliver St Thomas from the dilemma? The usual escape is by saying that he writes, not of human souls and angels as they are from the pure view of philosophy, in puris naturalibus, but as they actually are in the historical order of Providence, elevated to the supernatural state, destined and fitted by God's gratuitous bounty to see Him ultimately face to face. But the Saint's arguments in this chapter are purely rational and philosophical, containing not the slightest reference to any fact presupposed from revelation.
Or shall we say that he deals only in eikota, arguments of congruity, but not of necessity, or as he says (B. I, Ch. IX), rationes verisimiles ad fidelium exercitium et consolationem? Against this interpretation it is to be considered that the chapter is an essential link in a long chain of arguments (Chapp. XXVI-LIV) evidently meant for a demonstrated theory of happiness.
I think we should consider what St Thomas would have said to the following reply to the argumentation of this chapter.
There is no natural desire of that which created nature, as such, is not capable of attaining in any shape or form.
But created nature, as such, is not capable of attaining, in any shape or form to the vision of God face to face: therefore.
This difficulty I doubt if St Thomas ever raised to himself, or had brought before him. It came into prominence three or four centuries later in the disputes with Baius and Jansenius. Had St Thomas been confronted with it, I am confident that he would have met it as Catholic theologians now do. He would have acknowledged that angels and human spirits, in their mere natural condition, would find satisfaction and perfect natural happiness in a vision of God mediate and indirect. He might possibly still argue a certain congruity in such intelligent creatures being raised to the supernatural state and made capable of seeing God. He might and he might not, for such elevation is a stupendous advance upon nature; and the vision of God, but for its being a revealed fact, would be beyond any creature's dream. It hath not entered into the heart of man to conceive (i Cor. ii, 9). But once raised to the supernatural order and endowed with grace, St Thomas would argue invincibly that there is no proper happiness for created spirits except face to face with the beauty and glory of God.
Of God and His Creatures: 3.50