Frederick D. Wilhelmsen's Being and Knowing, rooted in the philosophy of St. Thomas Aquinas, rests on two basic assertions: first, metaphysics is the science of being in its first and ultimate act, existence (the act by which all things manifest themselves); second, that existence is known not through observing objects, but in affirming through judgments that these objects are subjects of existence.

The chapters of this book explore these Thomistic doctrines. Some explain St. Thomas Aquinas's philosophy of being. Others probe his epistemology. The complexity and density of...