God: His Knowability, Essence, and Attributes: A Dogmatic Treatise, Prefaced by a Brief General Introduction to the Study of Dogmatic Theology

Here below man can know God only by analogy; hence we are constrained to apply to Him the three scientific questions: An sit, Quid sit, and Qualis sit, that is to say: Does He exist? What is His essence? and What are His qualities or attributes? Consequently in theology, as in philosophy, the existence, essence, and attributes of God must form the three chief heads of investigation. The theological treatment differs from the philosophical in that it considers the subject in the light of supernatural Revelation, which builds upon and at the same time confirms, supplements, and deepens the conclusions of unaided human reason. Since the theological question regarding the existence of God resolves itself into the query: Can we know God?-the treatise De Deo Uno naturally falls into three parts: (1) The knowability of God; (2) His essence; and (3) The divine properties or attributes.