Strewn throughout the innumerable pages of the Christian tradition are reflections about how it is possible for human beings to talk about God. Indeed, if by our understandings of God we mean something close to what the theologian Paul Tillich described as “ultimate concern,” there is little else that could rival this topic in terms of importance. It seems intuitive that we know what we mean when we say, for example, “God is good.” If he were not good, then he would not be God–at least not the God with whom we are familiar by way of the Incarnation. At the same time, though, we must also believe him when he says through the prophet Isaiah, “[M]y thoughts are not your thoughts” (Isa. 55:8). In other words, God cannot be contained by human “thoughts” like goodness or justice. The question is, then: How can we talk intelligently about God if he is nothing like we have ever thought or experienced in full?
This exact problem has been the subject of much contemporary debate surrounding problems of theology, philosophy and secularity, but perhaps its most classical conception occupies a significant part of Thomas Aquinas’ Summa Theologica. With characteristic clarity and precision, Aquinas navigates this problem using three terms. The first is “univocal” predication, which means something like the first perspective described above: namely, that predicates like “is good” or “is wise” can apply to both creatures and God in the same way and in the same respect. On this univocal perspective, it is possible to name the attributes of God by looking to our finite, created surroundings. But this is problematic, for Aquinas:
I answer that, Univocal predication is impossible between God and creatures. The reason of this is that every effect which is not an adequate result of the power of the efficient cause, receives the similitude of the agent not in its full degree, but in a measure that falls short, so that what is divided and multiplied in the effects resides in the agent simply, and in the same manner; as for example the sun by exercise of its one power produces manifold and various forms in all inferior things. (Part 1, Question 13, Article 5)
What Aquinas argues here is that “caused” things are never quite the same as their cause. This applies to the relationship between creation and Creator. Like the sun’s distribution of heat throughout the earth, God’s attributes are distributed throughout his creation in a limited way. After all, the heat of the sun’s surface is different from the heat of the sun in an Arizona summer–not only in terms of degree, but also in kind. Although the poor souls in Arizona can apply the predicate “is hot” quite intelligibly in their own earthly context, that same “is hot” is different for the sun because the sun is hotness to begin with. Thus, only insofar as this important qualification holds can the predicate “is hot” apply to both Arizona and the sun.
So, if univocal predication is problematic, what about equivocal predication, which assumes the opposite perspective: namely, that there is no similarity between predicates of God and of creatures? Again, Aquinas is critical of such an “all or nothing” perspective:
Neither, on the other hand, are names applied to God and creatures in a purely equivocal sense, as some have said. If that were so, it follows that from creatures nothing could be known or demonstrated about God at all; for the reasoning would always be exposed to the fallacy of equivocation. Such a view is against the philosophers, who proved many things about God, and also against what the Apostle says: “The invisible things of God are clearly seen being understood by the things that are made” (Romans 1:20)
Aquinas’ reasoning is straightforward here. If such a perspective on equivocal predication is assumed, then meaningful speech about God is impossible. But this is a direct assault on the integrity of the words of Paul (among others), who clearly does not accept such a terrible consequence.
The solution to this dilemma for Aquinas, then, is his version of analogical predication: “Therefore it must be said that these names are said of God and creatures in an analogous sense, i.e. according to proportion.” Unlike univocity and equivocity, which bear in themselves difficult and extreme consequences for Christianity, analogy represents a sort of via media:
[W]hatever is said of God and creatures, is said according to the relation of a creature to God as its principle and cause, wherein all perfections of things pre-exist excellently. Now this mode of community of idea is a mean between pure equivocation and simple univocation. For in analogies the idea is not, as it is in univocals, one and the same, yet it is not totally diverse as in equivocals; but a term which is thus used in a multiple sense signifies various proportions to some one thing.
Predication of creatures is similar to predication of God only as a limited proportion of its very source. Thus, simply by being themselves, created things participate in God in different ways and to different extents. Instead of understanding the composition of all creation in terms of isolated, self-sufficient entities, this analogical vision understands things only as their relationship to God indicates. Indeed, the very meaning of being itself is a relationship to God.
Now, the consequences of this vision of reality are literally as innumerable as the amount of things in reality itself. Perhaps what is most remarkable about Aquinas’ conception of analogy is its unparalleled emphasis on the omnipresence of God. Since all things participate in the divine simply by virtue of their very existence, there is a profoundly hopeful spirit about the world and its future prospects. After all, according to the doctrine of analogy, we do have some idea of what we mean when we talk about what is of “ultimate concern.”