ABSTRACT
The Scholastic debate in thirteenth century Paris over the roles of faith and reason in determining knowledge gave rise to several brilliant paradigms which allowed for a synthesis of these two modes of knowing. Thomas Aquinas proposed a solution which considered reason, like faith, as a means of knowing God, a solution which integrated faith and reason. He articulated this description of reason as complementary to faith in Summa Theologica I, in which he addresses the evidence required for knowledge of God:
ex quolibet autem effectu potest demonstrari propriam causam eius esse (si tamen eius effectus sint magis nod quoad nos), quia, cum effectus dependeant a causa, posito effectu necesse est causam praeexistere. unde deum esse, secundum quod non est per se notum quoad nos, demonstrabile est per effectus nobis notes.
Ad primum ergo dicendum quod deum esse, et alia huiusmodi quae per rationem naturalem nota possunt esse de deo, ut dicitur rom. i ‘non sunt articuli fidei, sed praeambula ad articulos, sic enim fides praesupponit cognitionem naturalem, sicut grada naturam, et ut perfectio perfecdbile.’ nihil tamen prohibet illud quod secundum se demonstrabile est et scibile, ab aliquo accipi ut credibile, qui demonstrationem non capit. 1
When an effect is better known to us than its cause, from the effect we proceed to the knowledge of the cause. And from every effect the existence of its proper cause can be demonstrated, so long as its effects are better known to us; because since every effect depends upon its cause, if the effect exists, the cause must pre-exist. Hence the existence of God, in so far as it is not self-evident to us, can be demonstrated from those of His effects which are known to us.
The existence of God and other like truths about God, which can be known by natural reason, are not articles of faith, but are preambles to the articles; for faith presupposes natural knowledge, even as grace presupposes nature, and perfection presupposes something that can be perfected. Nevertheless, there is nothing to prevent a man, who cannot grasp a proof, accepdng as a matter of faith, something which in itself is capable of being sciendfically known and demonstrated. 2
In this passage, Aquinas defines the role assumed by reason by establishing the necessity of knowledge which is derived through a perception of sensible things. He continues by arguing that natural knowledge does not exist in opposition to faith, but works together with faith. In constructing this argument, he avoids creating a hierarchical relationship between faith and reason, in which one mode of knowing would dominate the other. Faith, though essential, and the primary means to knowledge of God, does not serve as the only means to knowing God. In Question 1 of the Summa, Aquinas states that there exist such things which are knowable through faith or reason, and other things knowable only through faith. Thus, faith and natural reason may achieve the same goal through different means. Aquinas is able to assert the importance of natural reason without questioning the essential role of faith.