Abstract
Whether Trinitarianism is coherent depends not only on whether some account of the Trinity is coherent, but on which accounts of the Trinity count as "Trinitarian." After all, Arianism and Modalism are both accounts of the Trinity, but neither counts as Trinitarian (which is why defenses of Arianism or Modalism don’t count as defenses of Trinitarianism). This raises the question, if not just any account of the Trinity counts as Trinitarian, which do? Dale Tuggy is one of very few philosophers to give explicit definitions of Trinitarian (versus Unitarian) theology. But they are no mere formalities. They are essential to his central criticisms of both historical and contemporary forms of Trinitarianism. In this paper, I offer my own definitions of Trinitarian and Unitarian theology, contrast them with Tuggy’s, and argue for the superiority of my definitions to Tuggy’s. If Trinitarianism and Unitarianism are what Tuggy says they are, the outlook for Trinitarianism is bleak indeed. If they are what I say they are, Tuggy’s central objection to Trinitarianism fails. To show what is at stake in these pairs of definitions, I examine a doctrine much neglected in Analytic Theology, but central to Nicene Trinitarianism—the Monarchy of the Father.