“For a thing is said to more noble or less noble, more perfect or less perfect in the measure in which it is a determined mode in the scale of perfection. … [P]erfection is only a certain way of being. … A white thing … cannot be perfectly white because it is not whiteness; it is white only in that it participates in whiteness, and its nature is perhaps such that it cannot participate in integral whiteness. But if there existed a whiteness in itself and whose being consisted precisely in being white, it would not be deficient in whiteness in any degree. Similarly for what concerns being. … We affirm [says St. Thomas in De Potentia 3, 4, “I answer that”] proceed from God by way of knowledge and intelligence. By this mode, a multitude of things can proceed immediately from a God who is one and simple and whose wisdom embraces all beings [Nos autem ponimus, quod a Deo procedunt res per modum scientiae et intellectus, secundum quem modum nihil prohibet ab uno primo et simplici Deo multitudinem immediate provenire, secundum quod sua sapientia continet universa].” (emphasis added)
A cornerstone of Thomism is that “ens et verum convertuntur” (being and truth are convertible with each other). Recall that the convertibility of being and truth (cf. ST I, q. 16, a. 2–3; De Ver. q. 1, a. 1) means that a thing’s degree of intelligibility corresponds to the thing’s degree of being. “For being cannot be understood, unless being is intelligible (Non enim potest intelligi ens, quin ens sit intelligibile)” (ST I, q. 16, a. 2 ad 3). “That thing” is less intelligible than, say, “that large white cat on the mat in a hat” because the former’s existence is closer to the inchoate vagueness of prime matter, and thus farther from the specific existence of a substantial form. A white object’s perfection consists in being intelligible as an object that participates in whiteness itself. Whiteness itself enjoys a higher level of being because it is more intelligible––it is recognized in the myriad of white things, whereas the whiteness of particular white things is recognized as dependent on the broader intelligible existence of whiteness itself.
Alternatively phrased, whiteness itself is more intelligible because its higher degree of being allows it to exist in numerous instances. Whiteness itself is more intelligible than any of its instances, not only because it is known in each of its instances, but also because it is the element which makes those instances intelligible as white things. Necessarily, one knows whiteness itself in any of its instances, but the converse does not hold: one does not necessarily know any of the instances of whiteness until one encounters them empirically. Thus, our intellectual grasp of the intelligibility of whiteness embraces within it, albeit imperfectly, the multitude of white instances. Our grasp of them is imperfect since we must still encounter them empirically to see how they “match up” with our grasp of whiteness itself. In a perfect manner, by contrast, God’s wisdom embraces all beings (sua sapientia continet universa), both in their formal perfection and in all their instances.
This is, I believe, the crucial conceptual background for the Fourth Way. The intelligibility of the perfection of any genus exists by virtue of its being intelligible in God’s wisdom. What His wisdom does not fathom or countenance, does not exist. Diverse objects partake of various perfections to varying degrees, but their ordering in intelligibility, and their particular modular acts of existence, depends on being known as the ordered effects of God wisdom in creating and sustaining them.