In the third volume of his magisterial Post-Reformation Reformed Dogmatics<\/em>, Richard Muller offers a helpful summary of pre-Reformation discussions of divine simplicity. Today, simplicity is making a comeback, taken as essential to orthodoxy. Muller\u2019s discussion is a healthy reminder that \u201cthe doctrine of divine simplicity has not always been understood in the same way or received the same emphasis in theology.\u201d<\/p>\n At a minimum, simplicity provided a way of buttressing unity and heading off any idea of composition, and hence of dependence. Muller writes, \u201c\u201cThe doctrine of divine simplicity . . . belongs to the full locus de Deo<\/em>, the larger topics of essence, attributes, and Trinity\u2014and it belongs there as having the specific function, not of ruling out distinctions per se, but of allowing only those distinctions in the Godhead that do not disrupt the understanding of the ultimacy and unity of the One God. With very few exceptions in the history of the doctrine, discussion of simplicity, in the context of the full locus, provides the place at which the datum<\/em> of divine oneness is coordinated with one level of distinction ad intra<\/em>, corresponding with the distinction of attributes, and another level of distinction ad intra<\/em>, corresponding with the necessarily different distinctions among the three divine persons.\u201d<\/p>\n Citing the work of Basil\u00a0Krivocheine, for instance, Muller claims that in Nyssa,\u00a0\u201cthe notion of simplicity is seen to be the exclusion only of compositeness and division, not of other kinds of distinction, notably the distinction between divine hypostases and divine energies or powers.\u201d<\/p>\n In Augustine too, simplicity was compatible with certain kinds of ad intra<\/em> distinctions:\u00a0\u201cAugustine affirmed the divine simplicity on the ground that God is not composite and is devoid of accidents and did so primarily in the context of the doctrine of the Trinity as an affirmation of the fundamental unity and uniqueness of the Godhead. Nonetheless, Augustine indicated that (in addition to the distinction of the persons in the Trinity), there was some distinction of attributes: he spoke of God as \u2018both simple and manifold,\u2019 having a \u2018simple multiplicity or multifold simplicity.'\u201d In his doctrine of divine ideas, further, \u201cAugustine also assumed that God knows these distinct ideas as distinct ideas.\u201d<\/p>\n Theologians of the middle ages \u201ctook a patristic conception that, in its most strict forms, could stand in a problematic or paradoxical relationship to the distinction of divine attributes and the doctrine of the Trinity, and worked to develop a more nuanced and flexible concept that could rule out composition while at the same time allowing for the \u2018operational complexity\u2019 of the Godhead.\u201d More elaborately that patristic writers, the medievals \u201cargued that the identification of \u2018simplicity\u2019 as uncompoundedness did not rule out either the distinction of divine persons or the distinction of divine attributes. Indeed, it would be one of the burdens of scholastic argumentation to identify precisely what kinds of distinction there might be in the simplicity or uncompoundedness of the Godhead.\u201d<\/p>\n Operating within a Platonic frame, Anselm affirmed simplicity against the notion that there are accidents in\u00a0God. For Anselm, this was largely a way to affirm aseity: \u201cit is the same for God to be just and to be justice itself, given that the justness or righteousness of God is not a separable property as righteousness is in human beings. This must be so, Anselm argues, inasmuch as God is just through himself, not through or on the basis of a prior justice in another.\u201d<\/p>\n