When we say a human being is good, we have a reasonably clear sense of what we mean. But when we turn around and say God is good, are we using the word in exactly the same way? Thomas Aquinas thought the answer had to be no—and that getting this wrong would quietly wreck the entire enterprise of theology.

The question sounds pedantic until you feel its force. If 'good' means precisely the same thing applied to God and to a generous neighbor, then God starts to look like just another member of the universe—bigger, perhaps, but not fundamentally different. If 'good' means something completely different when applied to God, then we have no idea what we're saying when we praise divine goodness. Either way, theology collapses.

Aquinas proposed a middle path: analogical predication. Words like 'good,' 'wise,' and 'just' apply to God neither univocally nor equivocally, but analogically. This article examines why that distinction mattered so urgently, how analogy is supposed to work, and whether contemporary philosophers think Aquinas actually pulled it off.

Begin with the two horns of the dilemma. Univocal predication means a term carries the same definition across every use. If 'wise' means exactly the same thing when applied to Socrates and to God, then God's wisdom is just a scaled-up version of human wisdom—differing in degree, not in kind. For Aquinas, this is a category error. God is not a being within the world but the transcendent source of all being. Treating divine attributes as univocal with creaturely attributes effectively domesticates God, reducing the infinite to a finite concept.

The opposite extreme is equivocal predication. Here, 'wise' as applied to God and 'wise' as applied to a human share nothing but spelling. The word is a mere homonym, like 'bank' meaning a riverbank or a financial institution. If theological language is equivocal, then every claim about God's nature—God is good, God is just, God is loving—is semantically empty. We mouth the words without any determinate content. Religious discourse becomes a kind of pious noise.

Aquinas recognized that both options are fatal. Univocity collapses the Creator-creature distinction, the foundational asymmetry in classical theism. Equivocity collapses the possibility of rational theology altogether. If we can say nothing meaningful about God, then Scripture, creed, and philosophical argument are all equally vacuous. The stakes are not merely linguistic; they are existential for the theological project itself.

This is why the question of religious language occupied such a central place in medieval philosophy. It was not a side issue in semantics. It was the gatekeeping problem: can we speak about God at all, and if so, under what conditions? Aquinas's doctrine of analogy was his attempt to thread the needle—to preserve genuine cognitive content in theological claims while honoring the radical otherness of the divine nature.

Takeaway

Religious language faces a dilemma: say God is just like creatures and you lose transcendence; say God is utterly unlike creatures and you lose meaning. The entire credibility of theology depends on finding a third option.

Aquinas's solution draws on Aristotle's insight that some terms have a focal meaning—a primary sense from which derivative senses radiate. 'Healthy' is the classic example. We call an organism healthy in the primary sense, then call food healthy because it causes health and urine healthy because it indicates health. The word is neither purely univocal across these uses nor arbitrarily equivocal. There is a controlled relationship between its senses.

Applied to God, the logic runs as follows. Creaturely goodness is real, but it is participated goodness—received from and dependent upon a source. God's goodness is that source: goodness itself, subsisting without limitation. When we say a person is good and God is good, the term 'good' is applied primarily to God (in whom goodness is identical with existence) and derivatively to creatures (who possess goodness as a limited participation). This is the analogy of attribution: the creaturely perfection points back to its causal origin in God.

Crucially, Aquinas adds the analogy of proportionality. God's goodness stands to God's nature as human goodness stands to human nature. We do not grasp God's nature directly, but we understand the proportional relationship. This gives theological predication genuine content—it is not a blank check—while acknowledging that we cannot comprehend how goodness exists in God in the way we comprehend it in creatures. The concept is stretched beyond its ordinary range, but it does not snap.

The metaphysical backdrop is essential. For Aquinas, God is ipsum esse subsistens—subsistent being itself. Every creaturely perfection (goodness, wisdom, justice) is a limited participation in the unlimited divine act of existence. Because effects bear a real, if imperfect, resemblance to their cause, language rooted in creaturely experience can reach toward God without pretending to capture the divine essence exhaustively. Analogy, then, is not a rhetorical trick. It is grounded in the causal structure of reality as Aquinas understands it.

Takeaway

Analogy works because creatures really do derive their perfections from God. The language isn't arbitrary; it's anchored in a causal relationship—like reading a reflection that genuinely, if imperfectly, discloses its source.

Analytic philosophers of religion have pressed hard on whether Aquinas's analogy actually delivers what it promises. The most persistent objection: if we cannot specify how God's goodness differs from creaturely goodness, do we really have meaningful content, or just a promissory note? Alvin Plantinga has argued that univocal predication is not as dangerous as Aquinas feared—that we can say God is wise in the same sense we are wise, only without the limitations, and that this preserves both transcendence and intelligibility.

Plantinga's move is to distinguish the concept of a property from the mode of its realization. God and humans can share the same property—wisdom—even if God instantiates it in a radically different mode (infinitely, necessarily, timelessly). On this view, univocity at the conceptual level is compatible with vast metaphysical difference at the level of instantiation. The worry about domesticating God, Plantinga contends, confuses these two levels.

Defenders of analogy respond that Plantinga's proposal smuggles in the very comprehension Aquinas was trying to guard against. If we claim to grasp the same property in God and creatures, we implicitly claim a kind of intellectual access to the divine nature that classical theism denies. The debate turns on a deep question in philosophical theology: how much can a finite mind know about an infinite being? Analogy respects the epistemic gap; univocity risks pretending the gap doesn't exist.

Other contemporary approaches sidestep the debate entirely. Negative theology (apophaticism) insists we can only say what God is not. Wittgensteinian fideists argue that religious language operates within its own self-contained form of life and need not answer to external semantic standards. Each approach carries costs. Negative theology risks saying nothing at all; fideism risks insulating faith from rational critique. Aquinas's analogy, whatever its difficulties, at least attempts to hold meaning and mystery in productive tension—a tension that remains unresolved and philosophically alive.

Takeaway

The question isn't settled. Whether analogy, univocity, or some other framework best preserves both the intelligibility and the mystery of God-talk remains one of the most consequential open problems in philosophical theology.

Aquinas's doctrine of analogy was never just a semantic preference. It was an attempt to chart the narrow passage between two theological disasters: a God so familiar that transcendence dissolves, and a God so alien that language falls silent.

Whether analogy fully succeeds is genuinely debatable. But the problem it addresses is not optional. Anyone who wants to make meaningful claims about a transcendent God must eventually confront the question of how finite words reach an infinite subject.

The enduring value of the debate lies here: it forces us to be honest about what we can and cannot say—and to take that honesty seriously as a philosophical and spiritual discipline.