Philosophy is a tradition of rational inquiry into the most basic principles of existence. There are various ways of defining this inquiry. Etymologically, the Greek term philosophia means "love of wisdom." But what is wisdom? Representing an older metaphysical tradition, Leibniz said that the very first question philosophy should ask is, "Why is there something rather than nothing?" Philosophy thus understood is concerned with the source and nature of being; this is what philosophy fundamentally meant for Plato, Aristotle, and Aquinas. Turning away from this metaphysical tradition, Immanuel Kant later tried to capture the tasks of philosophy in the three famous questions, "What can I know? What ought I to do? What can I hope?" The nature of philosophy is itself part of the philosophical debate.
Philosophy overlaps with many other disciplines: the question of knowledge, for example, has implications that touch on psychology and neuroscience. In dealing with ethical questions, the philosopher may need to be in dialogue with medicine (medical ethics), biology (environmental ethics), or economics (business ethics). Philosophy of language partially overlaps with linguistics, while the philosophy of religion is related to religious studies. What always distinguishes the philosophical approach, however, is its focus on fundamental principles not reducible to natural science or empirical data. Furthermore, although philosophy is a theoretical discipline that is engaged in a disinterested quest for knowledge, most philosophers, from Plato to the present, have also considered philosophy as an existential quest for the true and the good. Philosophers, one could say, do not only want to understand the world; they want to lead a life which reflects this understanding.
In asking questions concerning the foundations of human existence, philosophy is not unlike theology. It is not surprising, therefore, that many Western philosophers—especially in the patristic and medieval periods—were also or even primarily theologians. There are, however, important differences between the two disciplines: although many of the questions that philosophy and theology ask are the same, they arrive at their answers by different means. Whereas theology draws on Scripture and Tradition as its principal sources, philosophy relies on reason and human experience. Philosophical inquiry is therefore accessible to believers and non-believers alike.
Philosophic studies at the University of Dallas have three features that set the UD philosophy program apart from many others. First, UD philosophy students read the great philosophers themselves, not textbook summaries. The core courses and the historical courses, in particular, focus on the study of some of the most influential texts of the Western philosophical tradition, from Plato's Republic, Aristotle's Metaphysics, Augustine's Confessions, and Thomas Aquinas's On Being and Essence to Descartes' Meditations, Kant's Prolegomena, and Heidegger's Being and Time. Second, majors in the UD philosophy program receive a solid grounding in the history of Western philosophy. In this fashion, they acquire an understanding of not merely an isolated thinker or theory, but of the unfolding of the philosophic tradition as a whole. Third, as a philosophy department at a Catholic university, the UD philosophy program encourages dialogue with theological texts and ideas.
The department houses the editorial offices of the Dallas Medieval Texts and Translations series, which publishes medieval Latin texts with accompanying English translations. It also organizes an annual Aquinas Lecture, which has attracted outstanding philosophers from the U.S. and abroad.