Aquinas on Relationship Between Faith and Reason

From at least the days of the Greek philosophers, the relationship between faith and reason has been hotly debated. Plato in the Republic argued that the most perfect knowledge is memory of the eternal. Aristotle in his Nicomachean Ethics set down rules by which moral knowledge could be discovered by reason. In the Middle ages the relationship between faith and reason was among the main issues of the time. "Faith seeking understanding" was a motto for St. Augustine, and St. Anselm borrowed the same motto some centuries after. Nevertheless, later on, St. Bernard and some other churchmen of his time maintained that philosophy or mere reason should not concern itself in any way with the articles of faith (Jones 211). In opposition to this belief of St. Bernard, St. Thomas Aquinas held that it is possible to demonstrate many religious truths by the natural light of reason (212); in the same vein, he propounded the link and relationship between faith and reason and between theology and philosophy.

This paper will discuss Aquinas' explanations on the relationship between faith and reason. In my discussion I will follow the following sequence: First, I will elucidate how Aquinas expounds faith and reason and clarifies the difference between these two. Second, I will show the relationship between faith and reason as portrayed by Aquinas. Finally, I will discuss his position that pertains to this relationship and end with a conclusion.

To begin with descriptive definitions, Aquinas sees reason and faith as two ways of knowing. "Reason" covers what we can know by unaided experience and logic operating alone. From reason, we can know that there is a God and that there is only one God. Aquinas asserts that these truths about God are accessible to anyone by experience and logic operating alone, apart from any special revelation from God; whereas "faith" covers what we can know by God's special revelation to us (which comes through the Bible and Christian tradition). Aquinas portrays that by faith we can know that God came into the world in Jesus Christ and that God is triune (Father, Son, and Holy Spirit). These truths about God, according to Aquinas, cannot be known by unaided reason (55).

In his works - the Summa Contra Gentles and the Summa Theologiae, to which I will refer - Aquinas portrays the difference between faith and reason and theology and philosophy as he used the terms. For him, the first and major formal difference between theology and philosophy is found in their principles, that is, their starting points. The presuppositions of the philosopher that to which his discussions and arguments are ultimately driven back, are in the public domain; they are truths that everyone can know upon reflection using reason (56). In addition, for Aquinas, these principles are not themselves the products of proof, but it does not mean that they are immune to rational analysis and inquiry; thus, they are said to be known by themselves (per se) (57). Aquinas asserts that this is proportionately true of each of the sciences, where the most common principles just alluded to are in the background, and the proper principles or starting points of the particular science function regionally as the common principles do across the whole terrain of thought and being (58).

By contrast, according to Aquinas, the discourse of theology is ultimately driven back to starting points of principles that are held to be true on the basis of faith; that is, as he continues to explain, the truths that are authoritatively conveyed by revelation from God. Furthermore, as he explains, this theological discourse looks like any other discourse and is, needless to say, governed by the common principles of thought and being; but it is characterized formally by the fact that its arguments and analysis are taken to be truth-bearing only for one who accepts revelation in Scripture and Christian tradition as true.

Moreover, Aquinas states that this difference provides a formal test for deciding whether a piece of discourse is philosophical or theological. He asserts that if the discourse relies only on truths anyone can be expected to know upon experience and reflection, and if it offers to lead to new truths on the basis of such truths, and only on that basis, then it is philosophical discourse. On the other hand, a discourse whose cogency depends upon our accepting as true such claims as that there are three persons in one divine nature, that our salvation was effected by the sacrifice of Jesus, that Jesus is one person but two natures, one human, one divine, and the like, is theological discourse (Daniel 293). In addition, Aquinas clarifies that any appeal to an authoritative scriptural source as the necessary nexus in an argument is thereby other than philosophical discourse and it does not qualify as unaided reason (Davies 33).

Although Aquinas propounded the difference between faith and reason, he further showed that the two work together harmoniously in what he calls 'reasonable faith'. In this relationship between reason and faith and between philosophy and theology, Aquinas holds that faith in eternal salvation shows that theological truths exceed human reason. But he also claimed that one can attain truths about religious claims without faith, though such truths are incomplete (Daniel 53). In chapter six of the Summa Contra Gentiles, Aquinas elucidates the reality of reasonable faith or relationship between faith and reason and between theology and philosophy in two senses:

The first is what he calls Preambles of faith: the revealed truths that natural reason can, in principle, come to knowledge of without the aid of divine revelation such as truths of the existence of God , that God is one, God is good and the like (Aquinas 298).

The second is what he calls Mysteries of the faith or the revealed truths that natural reason cannot even in principle come to knowledge of without the aid of divine revelation: such truths as Trinity of God and Christ God incarnated (299). Here Aquinas claims that these truths about God exceed human natural cognitive capability because human intellects are naturally limited to begin with the data of sense experience and God is beyond the data of sense perception. Therefore, it would be foolish for anyone to think that something is false merely because it falls outside the scope of human reason to logically demonstrate. This consideration is strengthened by comparison with everyday knowledge in which we discover that we are ignorant of many of the intelligible features of the natures of physical things which fall within the scope of human experience.

Aquinas emphasizes the interrelationship between faith