Aquinas Reconsidered (Part 2)
Note: This is the second part of Richard A. Muller's review of Thomas Aquinas by K. Scott Oliphint. Read part one here.
Oliphint's discussion of Aquinas' view of God draws heavily on the claims of Cornelius Van Til, one of whose basic points of critique is that Aquinas' "idea of the analogy of being compromises the biblical doctrine of creation."1 In Van Til's view, the notion of an analogy of being comes directly from Aristotle and reduces the distinction between the Creator and the creature by adopting the Greek philosophical assumption that "all being is essentially one" and that "all individual beings are being to the extent that they participate in this one ultimate being."2 What Van Til missed is that if Aquinas assumed "all being" is "essentially one," he would have had no need for analogy and simply identified the same attributes in God and in human beings as predicated univocally. But since Aquinas clearly affirms the Creator-creature distinction, resting on creation ex nihilo, he argued for non-univocal, namely analogical predication. Failure to understand the connection between Aquinas' understanding of analogy and his doctrine of creation is also characteristic of Oliphint's critique.
Oliphint also makes several crucial mistakes in his interpretation of Aquinas' proofs of the existence of God. He dismisses Aquinas' use of Exodus 3:14 as insufficient to show the Christian context in which the proofs are deployed on the rather slim ground that, had Aquinas really intended to be biblical, he would not simply have cited the verse he would have "shown how the content of revelation grounded his arguments" instead of proceeding by "natural reason."3 But citation of texts, presumably interpreted exegetically elsewhere, is a common practice, and this understanding of Exodus 3:14, rooted in Augustine, was a commonplace--not, by the way, available to "natural reason."
Nor is the citation of Exodus 3:14 the only indication of a theological and biblical backdrop to the proofs: in the first article, on whether the existence of God is self evident, Aquinas bases his argument with an objection drawn from John of Damascus' De fide orthodoxa and John 14:6--and then counters the objections with a point from Aristotle's Metaphysics interpreted by way of a reference to Psalm 52:1. In the second article, whether it can be demonstrated that God exists, draws objections from Hebrews 11:1 and from John of Damascus, countering them with a citation of Romans 1:20. Then, when Aquinas poses the question leading to the proofs of whether God exists, he offers no references in his objections and counters them with Exodus 3:14. The process of argument is on the basis of reason, but the argument with the objectors is an argument among Christians.
The second mistake is also categorical one: it concerns the issue of precisely what Aquinas thought he was proving. Oliphint represents Cajetan as teaching that the "proofs only demonstrated properties that could apply to a god, but not to God himself," (p. 90, n77) but what Cajetan actually held was that the proofs do not demonstrate the existence of God "per se" but "quasi per accidens," his point being that the proofs establish properties that, as Aquinas himself put it, "everyone understands to be God."4 These are not merely possible properties of "a god"--they are the presumed properties of the one and only God.
Another mistake concerns Oliphint's reading of Aquinas' cosmological proof. Oliphint draws on Stephen Davis to argue that "for any version of the cosmological argument to work, the conclusion must presuppose some aspect of temporal causality" and concludes that since Aquinas' does not place God into a temporal sequence, Aquinas' proof fails (p. 81). Aquinas, however, assumed creation ex nihilo and that there is no time, finite or infinite, before the moment of creation. Aquinas' view of the impossibility of an infinite sequence of causes, therefore, does not rely on temporal sequence but follows precisely what Davis assumed might produce a valid argument, namely, an essential or ontological sequence of the hierarchy of causes in which contingent being (even if it were in an infinite temporal sequence) is not sufficient to explain its own existence.5 Indeed, contra Oliphint, Davis concludes that Aquinas rightly recognized that "No hierarchical causal series can regress infinitely; it must have a beginning."6
One particular aspect of Aquinas' approach to the traditional notion of divine simplicity comes to the fore in Oliphint's discussion, namely, the relationship between simplicity and the doctrine of the Trinity. His discussion is focused on a distinction between esse and id quod est. Oliphint has the correct translation of id quod est as "that which is," but his definition is wrong: "that which is" does not mean "essence or nature" (pp. 105, 130). Aquinas uses the Boethian esse-id quod est distinction to indicate the same issue as his own essence-existence distinction, which points directly toward Aquinas' stress on God as "He who is" (Exodus 3:14).
Oliphint's Van Tilian critique not only ignores what Aquinas actually argues, it is also quite untenable, whether from a historical, theological, or philosophical perspective. Thus, Oliphint:
If we begin with biblical revelation, however (something that Thomas's natural theology cannot do) we can begin with, instead of the categories of esse and id quod est, the one essence of God as three hypostases, or subsistences. In other words, we can begin, contrary to Aquinas, with the ontological Trinity. With these biblical categories in view, we are able to affirm both that God's essence is who he is and that there is no possibility that he could be otherwise, and that each of the three subsistences can and does act as that one essence (p. 109).
Pace Oliphint, distinction between essentia and subsistentia is not directly given in biblical revelation. It took the church more than three centuries after the close of the canon to arrive at this terminological solution to the problem of divine triunity. Aquinas, moreover, both confesses the doctrine and meditates at length on the issue of one essence in three subistences or hypostases. It is not clear why the post-biblical distinction between essence and subsistence, as used to explain the biblical issue that God is One and is also Father, Son, and Spirit, is any more "biblical" than the distinction between esse and id quod est, as used to explain the biblical point that God is Who He is.
Even with the post-biblical trinitarian language in view, we are quite unable to make clear "that God's essence is who he is and that there is no possibility that he could be otherwise." A series of qualifications of the term essence must be added, including the point that in God there is no real distinction between essence and existence, a point, as Aquinas indicated, that can be gathered from Exodus 3:14. Just setting forth the trinitarian formula of one essence and three hypostases does not satisfy the requirement for affirming, in Oliphint's words, "that each of the three subsistences can and does act as that one essence." Indeed, just to say that each of the three subsistences "can and does act" as one essence itself is a problematic usage that verges on tritheism: the issue of the trinitarian formula is that the three subsistences are the one essence. In order to complete the doctrine and clearly affirm that the three subsistences are the essence in such a way as not to imply composition, the doctrine of simplicity also needs to be present. And it is present in Aquinas' theology, and was present in the major patristic and Reformed orthodox formulations concerning the Trinity.
All of these aspects of Oliphint's argument are problematic, but they do not quite rise to the level of the underlying problem, namely, that Oliphint confuses epistemology with ontology. Both Aquinas and the Reformed orthodox writers begin with prolegomenal discussions in which Scripture is set forth as the primary authority in doctrinal matters--so that both actually do begin biblically. Neither Aquinas nor the Reformed orthodox begin with the "ontological Trinity" because both recognize that the proper beginning point of knowledge (as distinct but not separate from faith) cannot be a point of doctrine like the Trinity that is neither self-evident nor demonstrable. Oliphint has confused the principium essendi with the principium cognoscendi, and has failed to recognize that cognitive principia, more generally understood, are self-evident, incontestable notions, some directly available to reason, some given by revelation.
Read the third part of this review here.
Notes
1. Cornelius Van Til, A Christian Theory of Knowledge (Nutley: P&R, 1969), p. 160; cf. idem, A Survey of Christian Epistemology (S.l.: Den Dulk Christian Foundation, 1969), p. 60.
2. Van Til, Survey of Christian Epistemology, p. 60; idem, Christian Theory of Knowledge, p. 160.
3. Oliphint, Aquinas, pp. 60-61, referencing McInerny's reading of the preambles; cf. ibid., pp. 27, 51.
4. Aquinas, Summa theologiae, Ia, q.2, a.3, corpus.
5. Cf. Matthew Levering, Proofs of God: Classical Arguments from Tertullian to Barth (Grand Rapids: Baker Academic, 2016), p. 66, especially note 165.
6. Stephen T. Davis, God, Reason and Theistic Proofs (Grand Rapids: Eerdmans, 1997), p. 73.
