I conceive the Trinity doctrine as the proposition that there are three persons each of whom is God but just one being which is God. In two papers by Peter van Inwagen I distinguish three potential candidates for a reason that the Trinity doctrine is logically possible. First, a particular conjunction entailing the Trinity doctrine is formally consistent in relative identity logic. Second, the conjunction is formally consistent in the standard logic. Third, the conjunction shares a form in relative identity (...) logic with another logically possible conjunction. I explain how all these three reasons fail because of the distinction between logical possibility and formal consistency. In contrast to previous critiques, I dispense with epistemological and metaphysical assumptions about absolute and relative identity. Instead, I employ modal distinctions endorsed even by the inspirer of van Inwagen’s relative identity of the Trinity — the pioneering analytic scholastic Peter Geach. (shrink)

In recent years, many resourceful thinkers have brought a new clarity to the issues surrounding the doctrine of the Trinity. Two incompatible families of Trinitarian doctrine have been clearly distinguished: Social Trinitarianism and Latin Trinitarianism. I argue here that no theory in either camp has yet evaded the triune pitfalls of inconsistency, unintelligibility, and poor fit with the Bible. These two main approaches appear to be hopeless, and I argue that appeals to ‘mystery’ are no way to avoid the difficulties (...) at hand. Thus, the Trinitarian project is as yet unfinished. (shrink)

In recent work, philosophical theologians Michael Rea and Jeffrey Brower have formulated a precise way of understanding the doctrine of the Trinity along the lines of a contemporary constitution theory of material objects. Here I explain the theological and philosophical thinking behind their proposal, and give seven objections to it. Stepping back to consider methodology, I distinguish several goals a Trinity theory may aim at, and argue that the theory at hand achieves some but not others. Most importantly, it fails (...) as a Rational Reconstruction of creedal trinitarian claims. (shrink)

William Hasker replies to my arguments against social Trinitarianism, offers some criticism of my own view, and begins a sketch of another account of the Trinity. I reply with some defence of my own theory and some questions about his.

Contrary to a common assumption, I argue that there is full agreement between East and West on the issue of the relation between the divine essence and the divine persons. I defend this claim by using the understanding of universals found in D. M. Armstrong to cast light on the theories. Taking Gregory of Nyssa and John of Damascus as representatives of the Eastern tradition, I show that this tradition sees the divine essence as a numerically singular object that is (...) wholly present in each divine person. The Eastern tradition explicitly sees this object as a universal. The Western tradition – exemplified in Augustine and Aquinas – likewise sees the divine essence as a numerically singular object that is wholly present in each divine person. But this tradition customarily denies that such an object could be a universal, on the merely philosophical grounds that universals are divided amongst the particulars that share them, and thus cannot be numerically one. Having shown the fundamental consonance of the two traditions, I argue by way of conclusion that differences between social and non–social theories of the Trinity depend entirely on the nature and extent of the features that are supposed to distinguish the persons from each other. (shrink)

Contrary to a common assumption, I argue that there is full agreement between East and West on the issue of the relation between the divine essence and the divine persons. I defend this claim by using the understanding of universals found in D. M. Armstrong to cast light on the theories. Taking Gregory of Nyssa and John of Damascus as representatives of the Eastern tradition, I show that this tradition sees the divine essence as a numerically singular object that is (...) wholly present in each divine person. The Eastern tradition explicitly sees this object as a universal. The Western tradition – exemplified in Augustine and Aquinas – likewise sees the divine essence as a numerically singular object that is wholly present in each divine person. But this tradition customarily denies that such an object could be a universal, on the merely philosophical grounds that universals are divided amongst the particulars that share them, and thus cannot be numerically one. Having shown the fundamental consonance of the two traditions, I argue by way of conclusion that differences between social and non–social theories of the Trinity depend entirely on the nature and extent of the features that are supposed to distinguish the persons from each other. (shrink)

The Christian doctrine of the Trinity poses a serious philosophical problem. On the one hand, it seems to imply that there is exactly one divine being; on the other hand, it seems to imply that there are three. There is another well-known philosophical problem that presents us with a similar sort of tension: the problem of material constitution. We argue in this paper that a relatively neglected solution to the problem of material constitution can be developed into a novel solution (...) to the problem of the Trinity. (shrink)

La costruzione teologica come spazio dell'esperimento mentale. Una regolarità trascendentale per dare forma alla conoscibilità dell'esperienza.The theological construction as a space for mental experiment. A transcendental regularity to shape the experience understanding.