Some old, and no longer common, objections to the idea God does not illumine us.
1 Now, someone will object against the preceding statements. No light that is added to the power of vision can elevate this power to a vision of things which exceed the capacity of bodily sight, for the power of sight is able to see colored objects only. But divine substance exceeds all the capacity of a created intellect, even more than understanding exceeds the capacity of sense. Therefore, the created intellect could not be elevated by any adventitious light so as to see the divine substance.
2 Again, the light which is received in a created intellect is something created. And so, it is infinitely removed from God. Therefore, the created intellect cannot be elevated to the vision of the divine substance by this kind of light.
3 Besides, if the aforesaid light can in fact do this because it is a likeness of the divine substance, then since every intellectual substance, by the fact of being intellectual, bears the divine likeness, the very nature of any intellectual substance whatever is adequate to the divine vision.
4 Furthermore, if this light is created, then nothing prevents it from being created connatural with some creature; hence, there could be a created intellect which, by its own connatural light, would see the divine substance. The contrary of this has been proved.
5 Moreover, “the infinite as such is unknown.” Now, we have shown in Book One  that God is infinite. Therefore, the divine substance cannot be seen by means of the aforesaid light.
6 Again, there must be a proportion between the understander and the thing understood. But there is no proportion between the created intellect, even when perfected by this light, and the divine substance, because their distance apart still remains infinite. Therefore, the created intellect cannot be elevated to the vision of the divine substance by any light.
7 For these and similar reasons some men have been moved to assert that the divine substance is never seen by any created intellect. Of course, this position both takes away true happiness from the rational creature, for it can consist in nothing other than a vision of divine substance, as we have shown; and it also contradicts the text of Sacred Scripture, as is evident from the preceding texts. Consequently, it is to be spurned as false and heretical.
Notes And now the counter arguments. The attempted rebuttals above do not carry as much force with us, given that we routinely speak of infinities (in math).
8 Indeed, it is not difficult to answer these arguments. The divine substance is not beyond the capacity of the created intellect in such a way that it is altogether foreign to it, as sound is from the object of vision, or as immaterial substance is from sense power; in fact, the divine substance is the first intelligible object and the principle of all intellectual cognition. But it is beyond the capacity of the created intellect, in the sense that it exceeds its power; just as sensible objects of extreme character are beyond the capacity of sense power. Hence, the Philosopher says that “our intellect is to the most evident things, as the eye of the owl is to the light of the sun.” So, a created intellect needs to be strengthened by a divine light in order that it may be able to see the divine essence. By this, the first argument is answered.
9 Moreover, this sort of light raises the created intellect to the vision of God, not on the basis of a diminution of its distance from the divine substance, but by virtue of a power which it receives from God in relation to such an effect; even though it remains far away from God in its being, as the second argument suggested. In fact, this light does not unite the created intellect with God in the act of being but only in the act of understanding.
10 Since, however, it is proper to God Himself to know His own substance perfectly, the aforesaid light is a likeness of God, inasmuch as it conduces to the seeing of God’s substance. But no intellectual substance can be a likeness of God in this sense. For, since the divine simplicity is not equaled by any created substance, it is not possible for a created substance to have its entire perfection in the same identity; indeed, this is proper to God, as we showed in Book One , for He is being, understanding and blessed, identically. So, in a created intellectual substance, the light whereby it is beatified in the divine vision is one thing, while the light whereby it is in any sense perfected within its natural species, and whereby it understands in a manner proportioned to its substance, is quite a different thing. From this the answer to the third argument is evident.
11 Now, the fourth is answered by the fact that the vision of the divine substance exceeds every natural power, as we have shown. Hence, the light whereby the created intellect is perfected for the vision of the divine substance must be supernatural.
12 Nor does the fact that God is called infinite hinder the vision of the divine substance, as the fifth argument suggested. For, He is not called infinite in the privative sense, as quantity is. This latter kind of infinity is rationally unknown, because it is like matter devoid of form, which is the principle of knowledge. Rather, He is called infinite in the negative sense, like a self-subsistent form, not limited by matter receiving it. Hence, a being which is infinite in this sense is most knowable in itself.
13 Now, the proportion of the created intellect to the understanding of God is not, in fact, based on a commensuration in an existing proportion, but on the fact that proportion means any relation of one thing to another, as of matter to form, or of cause to effect. In this sense, then, nothing prevents there being a proportion of creature to God on the basis of a relation of one who understands to the thing understood, just as on the basis of the relation of effect to cause. Hence the answer to the sixth objection is clear.