The Holy Father next explains the proper interaction between faith and reason and between philosophy and theology. Philosophy is the study of ultimate truth under the natural light of reason. Theology is the study of the Catholic faith with revelation as its first principles. The purpose of theology is to permit a greater understanding of the faith so that it can be grasped more firmly (n. 93).
Reason supports faith and philosophy supports theology in the following ways:
- Reason prepares the way to faith. St. Justin and the apologists used philosophy as a “preamble” to the faith (n. 38). Philosophical logic shows how the Catholic faith is not contrary to reason, and it can demonstrate the errors of arguments against the faith. Thus, St. Clement of Alexandria called philosophy a “stepping stone to the faith” (n. 38).
- Reason can show that that there is a God and can demonstrate his primary attributes such as his power and divinity. Reason lays the foundation for faith and makes revelation “credible.” Reason is thus the common ground between believers and unbelievers.
- Faith without reason withers into myth or superstition. Deprived of reason, faith is left with only feelings and experience. It loses its universality (n. 48).
- Philosophy provides a language for theology. Its concepts and patterns of thought permit theology to have a logical structure and to be a true science (n. 65). For example, while the Real Presence in the Holy Eucharist is to be believed as a matter of faith, theology attempts to make it more understandable in terms of substance, accidents, transubstantiation, etc. Philosophical language permits theology to speak about God, the personal relations within the Trinity, God’s creative activity in the world, the relationship between man and God, and Christ’s identity as true God and true man, to take a few examples (n. 66).
John Paul also explains how faith supports reason and how theology supports philosophy:
- Human reason is inherently weak and inclined to error. Deprived of revelation, reason can go off course and miss its destination (n. 48). Faith warns reason against the paths that will lead it astray (n. 73). It shines light on the true paths (n. 79).
- Faith stirs reason to explore paths that it would not otherwise have suspected it could take (n. 56). It proposes truths that might never have been discovered by unaided reason. For example, the notions of free will and a personal God who is the Creator of the world have been crucial for the development of a philosophy of being. The Christian proclamation of human dignity, equality and freedom is reflected in modern philosophical thought (n. 76).
- Faith gives the philosopher the courage to tackle difficult questions such as the problem of evil and suffering, the personal nature of God and the metaphysical question “Why is there something rather than nothing?” (n. 76). His faith gives him the conviction that his reason will find solutions, much as a trustworthy map gives one looking for buried treasure the confidence to keep digging.
- Faith and spiritual life protect the philosopher from intellectual pride that would impede his ability to search for the truth. Faith, strengthened by love, facilitates the intellectual grasp of the truth about man and his real needs (n. 76).
Source: John E. Fagan, “Fides et Ratio (Faith and Reason).” from The Teachings of Pope John Paul II: Summaries of Papal Documents (New York: Scepter Publishers, 2005): 64-71. (catholiceducation.org)