In “Is Divine Simplicity a Mistake”, William Hasker argues that “the strong doctrine of divine simplicity is a mistake, one from which theology needs to be liberated.” With this sweeping charter, Hasker proceeds to critique the “traditional strong doctrine of divine simplicity, attributed to Aquinas and before him to Augustine.” The strong notion of divine simplicity is riddled throughout with category errors, logical failures, the “dehumanization” of God, and departures from the broader traditional understanding of God’s character.

Hasker begins with certain qualifications. “I speak here of views attributed to Aquinas and Augustine because interpretations of their views are bound to be controversial. I shall not undertake to resolve those controversies.”1 The project Hasker undertakes is not primarily about the historical questions concerning the views of past theologians, but about the truth of the subject-matter.

I recognize, of course, that it is often important to establish as accurately as possible the exact views of some historical figure, even though this will not be the purpose of the present essay. But once that has been done, this accomplishment is merely preliminary to raising the question: Do we have good reason either to agree or to disagree with the thinker in question2?

That Hasker is not engaged in historical research is clear from those with whom he engages. Neither St. Augustine nor any historical authority merits a single citation. St. Thomas Aquinas is cited few times, and a historian of his thought has one fleeting quotation.3 Hasker does not examine either Augustine’s or Aquinas’ accounts of what he means by the terms “will”, “knowledge”, “love”, “action”. And although Hasker does quote Aquinas’ account of what he terms “simple simplicity”4, he does not set forth Aquinas’ (or Augustine’s) formulations of the strong version from which he seeks to liberate theology. Attention is paid instead to the works of Eleonore Stump, Jeffrey Brower, and James Dolezal.

Nor does Hasker wish to address the key components of the metaphysical framework necessary to explain the traditional notion of divine simplicity, at least in the work of Augustine or St. Thomas. He raises the St. Thomas’ postulate of the identity of God’s existence and essence only to say suggest it may involve a confusion of categories and quickly move on, saying “we won’t pursue this example.”5 As any reader of St. Thomas knows, St. Thomas’ formulation of divine simplicity depends on the identity of existence and essence in God, and any treatment of divine simplicity that does not address this claim does not address Aquinas’ notion of simplicity. And Hasker raises a number of questions that Aquinas himself raises as objections and then answers; yet Hasker does so without any indication that he is aware of those discussions. For instance, Hasker asks, if God is actus purus, “how can he be free?”6 without giving any sign that Aquinas raises the question and provides an answer in a number of places.7

Had Hasker not held himself out as correcting the traditional views of Augustine and Aquinas, the neglect of what Augustine and Aquinas actually said would not be objectionable. Were Hasker’s purpose simply to limit his criticism to the recent and narrow confines of analytic philosophy of religion where Augustine and St. Thomas have colored the debate, little treatment of their views would be necessary.

Hasker does not observe these limitations. His goal, after all, is grandiose: to “liberate theology”, and he does not hesitate to pronounce a verdict on Aquinas’ motivation for the doctrine of simplicity8, or to declare that truthmaker theory represents a genuine advance in the traditional argument for simplicity,9, or to identify logical deficiencies in the traditional formulations of simplicity,10 to announce “we need to grasp the problem [of divine cognition] as it is conceived by Aquinas and his followers”11, and to lay out “Aquinas’ perspective” on the individuation of actions. That Hasker is targeting the view of St. Thomas is clear both from the judgments he makes in the course of his article and in the light of his overall purpose. Unfortunately this lets the paucity and inaccuracy of Hasker’s treatment of St. Thomas’ views undermine his entire argument. It should be uncontroversial that to criticize the position of another, one first must understand it; and that as an academic, one must both characterize it accurately and provide the textual grounds for that clarification.

Next time: Is simplicity contradictory?


  1. William Hasker, “Is Divine Simplicity a Mistake?”, American Catholic Philosophical Quarterly 90 (No. 4) 2016 669-725, p. 699. 

  2. Ibid. 699-700. 

  3. Aquinas is cited in footnotes 4, 20, 57, 58; John Wippel’s Metaphysical Themes in Thomas Aquinas II is quoted on p. 709. Some may argue that Garrigou-Lagrange would also be considered a historian of St. Thomas’ thought; I would not. Stump, Brower, and Dolezal all use St. Thomas as a resource in contemporary debates, and are not engaged in substantively historical work. 

  4. Ibid. 701 - 702. 

  5. Ibid. 703. 

  6. Ibid. 713. 

  7. Treatment of this question abound in St. Thomas’ corpus. See, for instance, DV Q. 24, art 3, Q. 23 art 1, and SCG I.82. 

  8. Is Divine Simplicity a Mistake?, p. 702. 

  9. Is Divine Simplicity a Mistake?, p. 705. 

  10. Is Divine Simplicity a Mistake?, p. 706. 

  11. Is Divine Simplicity a Mistake, p. 707.