1.3.6. What is the “principal mirror” by which we know God, and why? It is the rational mind (“reason in itself”), for this “had been made nearest and most related to His image and likeness.” Why was the rational mind made in the likeness of God? So that “through itself it might find Him by whom it was made.”
1.3.7. Hugh speaks of “what occurs to us first,” but he in fact lists at least four different things that first occur to the rational mind: first, that the rational mind is something (and not nothing); second, that it is none of the visible, corporeal things that it knows; third, that the rational mind is itself distinct from these visible things, being itself invisible; and fourth, that there are in fact invisible things.
1.3.8. Two more things that the rational mind knows: (a) that it did not always exist, and therefore had a beginning; (b) that it was not the cause of its own beginning.
1.3.9. The rational soul that did not exist was made by something that did, something that was the cause of the existence of everything else, and therefore something whose existence was itself necessary and without beginning. (Is this the closest we get to an argument for God’s existence from Hugh?
1.3.10. What the rational soul sees in itself (namely God as its cause), it also sees outside of itself: “without an author, [things] could have neither origin nor restoration.” Everything that is mutable must at some time not have existed (cp. Aquinas’s “third way”). In this they show themselves to have been made by God.
1.3.11. Not only does reason know through itself and external things that God exists, but it also knows that God is Triune, or three in one. Reason reveals that there should be “one principle and one end to which all things that existed from it might turn” and that without a single principle and ruler the world would lack unity. Hugh doesn’t explain here, however, how reason knows God also to be three.
1.3.13-16. Hugh discusses God’s immutability (1.3.13), which leads him to an aside on the bodily (1.3.15) and the spiritual (1.3.16) mutability of his creatures. Angels can neither grow nor shrink in substance, but they can experience passions of joy, grief, repentance, and desire. Their knowledge can also increase through learning or decrease through forgetfulness. Accordingly, they are subject to temporal change. While there is doubt on the matter, Hugh believes angels, being incorporeal, do not change in place, for they do not occupy space. They are speculations such as these that earned the medievals the Renaissance barb that they engaged themselves in endless and fruitless inquiries into “how many angels can dance on the head of a pin,” but again, Hugh raises these issues for a theological purpose, namely to better understand and highlight God’s own immutability: the created spirit “is not changed in place but in time; but that the creating Spirit is neither in place nor changed in place… nor changed in time, since He is absolutely invariable.”
1.3.17. God “substantially or essentially and properly and really is.” This is Hugh’s ways of saying that God is what most exists, indeed, that he is (as St. Thomas would later put it) existence itself (ipsum esse). It means that existing is part of God’s substance: it’s what he is. To be God is to be the one who exists. This means that God’s existence is not limited (“defined”) by what he is (as is the case with creatures), since God’s existence simply is what he is. Unlimited in this way, God must also be present in everything else that exists. Hugh answers objections that God’s omnipresence would involve his “defilement” by contact with human flesh.
1.3.18. The foregoing discussion of God’s omnipresence leads Hugh to a return to the subject of created spirits and place. His position is the paradoxical one that created spirits, while without spatial dimension and hence are not “circumscribed” by place, are nonetheless “enclosed” by place and that by nature and operation they can be “local.”
1.3.19-22. Not only does reason know God to be one, but it also knows God to be three, something made manifest in that which bears God’s likeness (1.3.19). For just as man’s wisdom or inner word is known only to himself but becomes manifest when it is “revealed through utterance,” so God’s own wisdom and inner word was hidden and invisible until he made it manifest through his extrinsic word (1.3.20). The more the things God has made are like God, the more perfectly do they manifest him, and this is especially the case with rational creatures who have been made in his image, and in whom is thus “the first trace of the Trinity.” This trace consists in the mind of the rational creature’s self-begetting of its own wisdom and subsequent love for that wisdom, in which “a kind of trinity arises, and oneness does not depart.” Never without his Wisdom or Love for his Wisdom, God is coeternal with his Love and his Wisdom (1.3.21). The mind-wisdom-love analogy articulates the plurality of persons within the godhead without compromising but preserving its fundamental unity (1.3.22).
1.3.23-25. Because of their differences, the persons of the Trinity were given different names according to their different roles. The Father was named Father because he begets the Son, the Son because he is begotten, and the Holy Spirit because he is “given for sanctification” (1.3.23). The Holy Spirit proceeds from and is given by both the Father and the Son. The persons are three only in those things that are “distinct and peculiar” to them, but are one in those things which are common (1.3.24). This brings up a limitation to the earlier mind-wisdom-love analogy, which is that in an individual rational creature, of course, mind and wisdom and love are not individual persons, are “certain affections and forms” of the individual who is a person (1.3.25).
1.3.26. Although power is (scripturally and traditionally) attributed to the Father, wisdom to the Son, and goodness to the Holy Ghost, these are in fact “common” to all three, and not even in a way that all three are powerful, wise, or good, but only one, because there is only one power, one wisdom, one goodness “in one nature and in one substance.” Hugh rehearses his earlier argument about why Scripture, to counteract the tendency towards erroneous thinking about the different members and names of the Trinity, particularly attributed power, wisdom, and goodness to the Father, Son, and Spirit, respectively, even though each of these are held in common.