Acquiring the famous reputation as the “angelic teacher” among the rest of the medieval philosophers because of his overwhelmingly influential and prominent struggle in brilliantly standing on guard the Christian theology during his time which was saw one of the heights of the attacks on Christianity, Thomas Aquinas made use of human reason in resolving the criticisms that beset the Christian Church.
Resorting to human rationality and argumentation in providing a substantial justification for the Christian doctrines that meddled specifically on the existence of God symbolized a staunch deviation from the tradition that preoccupied the minds of thinkers during the medieval period. His efforts at utilizing the Aristotelian concepts on metaphysics and epistemology alongside with reason roughly highlights his firm belief that even with the sufficiency of simple faith in establishing religious principles and the very existence of God the role of rational thinking in the strictest sense of the word can all the more fairly demonstrate the basic principles of the Christian faith.
One of the most prominent arguments Aquinas proposed is his Five Ways to prove God’s existence. Although Aquinas’ attempt at proving the existence of God has startling parallels to that of Anselm’s Ontological Argument, the former claims that the argument of the latter thinker is unacceptable for the reason that man cannot explicitly demonstrate the existence of God whose nature is beyond the immediate knowledge of man through the straightest means (Oppy). Utilizing what seems to be a sprouting method of his time, Aquinas attempts at filling the structure of the Christian faith by embracing the field of rationality along with faith as the backdrop of his arguments.
The Five Ways
First of the arguments raised by Aquinas is the argument for The Unmoved Mover. At the center of this argument is the premise that no object moves without a mover, or that all objects move because of a mover in the sense that the leaves of the trees rustle because they are moved by the wind; that the balls in the billiard table collide with other balls or move around the table because of the force delivered through the cue stick. A hundred other more examples can be provided. Nevertheless the very essence of all these illustrations is that no object moves without a mover.
Apparently, all the examples eventually lead to an infinite regress where no end can be perceived at first. However, Aquinas tells us that this is not really an infinite regress for there has to be the presence of a first mover which initiated the series of “movements”. At this point, Aquinas proceeds to remove the infinite regress by arguing that the first mover is God.
In a seemingly parallel argument, Aquinas’ second argument rests heavily on cause and effect relation. That is, nothing is caused by itself. In other words, each and every effect ultimately boils down to a certain cause, or that it is of necessity that every effect for it to be an effect in the strictest sense has to be caused by something right at the onset of it being an effect. Again, it might be observed that a line of argument leads to an infinite regress. However, it is not the case for an ultimate cause above anything else has to be responsible for the chain of causes and effects. For that matter, Aquinas resolves the regress by arguing that the first cause is God. This is the uncaused cause argument.
The third way offered by Aquinas in primarily proving the existence of God is the cosmological argument. At the core of this argument is the reference to time wherein material objects have not yet come into physical existence. All the objects that we may know today are virtually inexistent at such point in time. However, Aquinas goes on to argue that since all material objects already exist, there ought to be or have been something immaterial or non-physical which brought these objects into physical existence. In essence, Aquinas claims that God is the non-physical entity which brought about the material existence of these objects.
Another argument which Aquinas tries to raise is the argument from degree. This argument apparently focuses its premises on certain variations of comparisons between qualities among men and other objects thereby providing a sort of background for yet another claim that all objects in the world, in their numerous manifestations, greatly differ and outweigh any traceable similarity that may hold them together.
Thus, individuals may greatly differ in virtues, with one being an altruist and the rest vicious criminals aimed at furthering their personal ends. Nevertheless, even if people vary in these aspects, the contrast between them can only be achieved if we note of a certain referential point for all the degrees of comparison. The reference, then, should be one which is imminently a perfect maximum and that this maximum cannot possibly rest among men themselves. Hence, God is the perfect standard for all comparisons and is the ultimate reference.
Lastly, Aquinas raises the teleological argument which is essentially the argument that seeks to prove the existence of God using the perceived design of the objects in the world. If we are to look upon the structure of the things we may either directly or indirectly perceive in the world, it will eventually dawn upon our thoughts that everything has been designed in such and such ways, serving various purposes that are derived from the very configuration of things. Similarly, it can be inferred from such premise that, since everything is so designed accordingly, there ought to be a designer of all these things which is a necessity which follows from the given observation on the design of things. The designer, as Aquinas argues, is God.
Aquinas and human knowledge: faith and reason
For Aquinas, knowledge is the comprehension of the supreme principles of being which define the very inseparable essences of the ultimate understanding of man—that of the sophia and phronesis. While the former is very much concerned with the individual’s intellectual capacity to exercise speculative thinking or understanding, the latter is primarily concerned with the aligning of the individual’s life in line with its fitting end through the role of practical wisdom. These two are inherently mutual in conception and are basically brought together in man’s attempt at arriving at the knowledge of everything.
Moreover, this attempt of man in obtaining knowledge requires the aid of the Divine in such a way “that the intellect may be moved by God to its act.” Nevertheless Aquinas maintains that man by himself alone has the intrinsic and innate ability to grasp the knowledge of many things even without the special divine revelation. More specifically, natural revelation—revelations obtained through reason—is the truth which, due to man’s inherent human nature, is made accessible to each and every man. On the other hand, supernatural revelation allows man to comprehend the knowledge on the details of the existence and attributes of God requiring not merely reason but also faith.
It should be noted that Aquinas is not entirely disproving the role of reason in arriving at the comprehension of things. Quite on the contrary, Aquinas strongly argues for the primal role of reason in arriving at knowledge. Nevertheless, even if he ascribes a premium weight on the significance of rationality, he qualifies this claim by stating that faith still holds central importance, specifically in acquiring knowledge of the existence of God and several other religious matters.
It appears quite obvious, then, that the philosophy of Aquinas in addressing the inquiry on human knowledge of the world cannot be entirely separated from a religious perspective. In explaining the nature of man’s knowledge and how one is able to grasp an understanding of the universe, Aquinas reinforces his arguments at the bottom by infusing a religious strand in the heaps of his epistemological and metaphysical inquiry.
Aquinas on Aristotle
The philosophy of Aquinas, in its very focal point, is seen to be heavily tainted with the philosophy of Aristotle. Much of this claim, for one reason, rests on the historical perspective wherein several of the writings on the philosophy of Aristotle eventually reached the shores of Europe during the time of the Crusades. The ancient texts were then a part of French as well as Italian universities and institutions of education around the middle part of the thirteenth century.
Like Aristotle, Aquinas himself agrees and proposes the claim that man is in fact a rational animal wherein man is able to grasp an understanding of the world and to arrive at knowledge of the Divine through this reason. Though man is an entity imbued with reason, man can merely arrive at such a comprehension of the universe through empirical means. That is, man is capable of grasping knowledge of the world through his sensory experience. As Thomas Aquinas states, “whatever is known is known in the manner in which man can know it.”
Mortimer Adler argues that for the most part, Aquinas and Aristotle agree on several points. First, they both agree that the form of the state of affairs of material composites, which can be made known, must be received by the knower with the form detached from the corporeal substance. Consequently, by possessing the power to acquire such forms in such a way grants the idea that the knower is “potentially a knower” and is actualized when the knower receives these forms. Among other similarities in the ideas that exist between Aquinas and Aristotle, both in general put centrality on the rationality of man and the role of experience or sensory perception in acquiring or knowing objects.
Owing much of the philosophical content of Aquinas’ ideas from Aristotle, the former has a strong belief that reason and human experience can lead man to realizing and understanding the universe and, consequently, the existence of God. And at the time where philosophy is closely knitted to religious matters, Aquinas sought to further reinforce his arguments by injecting Aristotelian philosophy for rationality during the medieval times was one of the factors that seek to explain the universe from a point of view detached from any religious ascription. Thus, Aquinas appears to have ‘Christianized Aristotle’ in the sense that the former made much use of the latter’s philosophy in a context slanted towards religion. (Jenkins)
On theoretical knowledge
Aquinas conceived of theoretical knowledge as something which is the result of human rationality juxtaposed with sensory observation. That is, one can arrive at theoretical knowledge primarily through an observation of one’s world and arrive at a logical structure and correlation of these things through the functioning of reason. Though Aquinas may direct us to the premise that this rationality of man is imbued to all men by God, nevertheless this same rationality alongside with sensory perception addresses the question on how men are able to satisfy his inquiries on matters which are at first unknown to him.
For example, one may acquire the theoretical knowledge on the how the tides of the oceans rise and fall through visual perception first and foremost which later on proceeds with the functioning of reason in attaching causal relations to the observed phenomenon. A similar view can also be held towards volcanic activity, rise and fall of economic activity, and many others.
Dawkins, Richard. The God Delusion. Houghton Mifflin, 2006.
Gaarder, Jostein. Sophie’s World. Reissue ed: Berkley, 1996.
Jenkins, John I. “Intellectus Principorum.” Knowledge and Faith in Thomas Aquinas. Cambridge University Press, 2004. 101-61.
Oppy, Graham. “Some Historical Considerations.” Ontological Arguments and Belief in God. Cambridge: Cambridge University Press, 1996. 4-46.