Abstract

This dissertation is an historical and exegetical study of the concept of self-evidence as found in the works of the thirteenth-century philosopher and theologian St. Thomas Aquinas. I have sought to identify all of the explicit self-evident propositions found in the writings of the Angelic Doctor, to indicate the terminology of the discussions of self-evidence, and to provide a context for understanding the appeals to self-evidence in the corpus thomisticum. To this end, the dissertation is divided into six sections. ;The introduction of the dissertation presents an account of the general neglect the concept of self-evidence has received by many contemporary philosophers. ;The first chapter is an examination of Aquinas's various definitions or descriptions of self-evidence. By examining the various ways in which definitions can be formulated, it is argued that self-evidence can be viewed as an equivocal notion, for there are different senses in which terms can be defined. ;In the second chapter I turn to Aquinas's doctrine of intellectual habits to explain how Aquinas justifies some of the divisions of self-evident propositions into classes. I argue that, for Aquinas, the designation of a proposition as self-evident is always, in itself, an incomplete characterization, requiring that it be supplemented with a more specific account of the intellectual habit whereby the proposition can be cognized precisely as self-evident. ;The third chapter examines a significant epistemic problem surrounding the cognition of self-evident propositions. Particular attention is paid to Aquinas's often-neglected doctrine that the essences of material things are hidden to human beings. ;The fourth chapter returns to a presentation of intellectual habits as that which allows for self-evident propositions to be cognized as self-evident. I focus on the habit of faith, and examine some texts that suggest that the intellect can be fortified with supernatural habits. ;The final chapter examines Aquinas's views on the role of self-evident propositions in moral psychology and moral science. The seven explicit ethical self-evident propositions from Aquinas's writings are set forth and discussed, with particular attention to the nature of the practical syllogism in moral decision-making. ;A summary of findings completes the dissertation