They may have died so long ago but the entire history of human intellect or human thought has been and still pays reference to these two Greeks thinkers; Plato (347 BCE) and his student Aristotle (322 BCE). In essence, no generation has been able to successfully escape their form of thought or it's effects since then. All philosophers afterwards are either in agreement with or in opposition to Aristotelian or Platonic methods. Aristotelianism and Platonism gave birth to and provided a conceptual framework for all the main philosophical worldviews.
Plato is of course the more influential of the two because Aristotle was a student of Plato and it is fair to say that though most elements of Aristotle’s metaphysics differ from Plato’s, his premises are still very much Platonic. However, it is Aristotelian metaphysics that I find myself personally more inclined to. As such, I was happy to realise that after he was overlooked and rejected by earlier philosophers including the Jewish and early Christian thinkers like St Augustine in favor of Neo-Platonism, St. Thomas Aquinas picked him up. The shape of human thought has never been the same since then. He (Aquinas) learned of Aristotle from Jewish philosopher Maimonides. Maimonides had learned about him from the Muslim philosopher Averroes. The works of Aristotle had been translated by the Muslim philosopher Al-ma’mum (thanks to him). Surprisingly, the Islamic religion leaders were quick to discard Aristotle because they thought mixing religion and reason was retarded.
After having read Aristotle, St Aquinas immediately fell in love with Aristotle's metaphysics. He was however not satisfied with the Aristotelian God who was an unmoved mover thinking on his own thoughts. Being the genius that he was, he refused either to lose his faith or mindlessly believe. He realized that while reason and revelation (faith) are two distinct means of arriving at the truth, the two are not opposed but are complementary to each other. He therefore developed a new understanding of the place of reason in Christian human life, building from Aristotelian metaphysics or premises but arriving at a Christian God conclusion. Brilliant work Aquinas! The way I understand it is that Aquinas developed his own metaphysics mainly from Aristotelian metaphysics and then adopted some bit of Platonism from St Augustine for his ethics. Plausible.
However, piecing up and explicating his argument from his legendary book “Principles of human nature” takes a lot of effort for an ordinary reader because of his "middle-age" writing style. Here I have tried to pin down his argument and reconstructed it to make it well-defended and easy to follow. I am fortunate to have gotten to Aquinas via Aristotle, because if not, I would still be in the woods. Footnote: since there are two kinds of truths; epistemological truths and ontological truths, don't be confused, the argument was on the basis of ontological truths. Let us get started!
Aim: To prove that there is no two-fold truth; reason and faith are complementary and not in opposition to each other.
1. Natural reason is limited in regards to the knowledge of God.
Reason without the added benefit of revelation is limited in varying degrees because there is a gradation of intellectual abilities between species and amongst humans owing to the hierarchy of being and becoming of the mind. There is a gradation of intellect amongst humans in such a way that some human are more rational than others. There is a potential for knowing about God by natural means, potential but with limitations. One of the limitations is that much of our knowledge of God is by way of analogy as seen from Aristotle epistemology of abstraction. We tend to think of God by analogy to other persons. So that we predicate the goodness of God by analogy to goodness of created things.
Our limitations are intensified by our sinfulness. He continues to make a distinction between the "image" of God and the "likeness" to God in which Adam was created. For Aquinas, we are the image of God in that we are rational beings. However, markedly lesser degree of rationality than God. But it is in that regard that we image God. The likeness to God is the moral likeness, which was lost when Adam fell. The fall of likeness leaves our rationality partly operative, it does not directly damage human rationality. Yet it does affect it indirectly. How? Because a person may be likely prejudiced against certain conclusions, and the mind at times is distracted by "earthly" loves and desires. So the moral condition of the human soul is likely to affect indirectly the knowledge of God. So then natural reason has its limits regarding the knowledge of God.
2. Revelation declares what reason can demonstrate.
Yes plainly. Aquinas thinks that reason can demonstrate the existence of God and the immortality of the soul. But these are things that also revelation declares. Why? The reasons are pretty obvious. By virtue of the degrees of rationality, some people are not equipped for such rational work. It may be possible to demonstrate it, but because of ability or maybe because of time, some people may not be able to do it. Secondly, those who could engage in abstraction might find that it takes excessive time and effort because of the profundity of the topic and because of the weaknesses of their will, affecting the operation of the intellect.
3. Revelation declares things reason cannot attain by itself.
Reason cannot attain understanding of things like the doctrine of the trinity or incarnation. Reason can come so far, and revelation should pick it up.
4. Faith assents to the truths of revelation.
The truths of revelation may then be confirmed by reasoning. That is to say then that by evidence and arguments that makes plain that such beliefs are at least reasonable, even though you may not be able to demonstrate them conclusively. Reason can confirm the truths not necessarily prove them, by showing that the conclusion is reasonable granted the metaphysical framework. Thereby showing the reasonableness of certain truths of faith, for example to say that there is no logical objection to them, or nothing is self contradictory in them. This should be the role of philosophical theology.
5. Reason gains an (imperfect) understanding of those truths of faith (as demonstrated above).
6. Conclusion: Therefore, faith and reason are not opposed to each other because truth is ultimately one.
This is the summary of the argument:
Aim: To prove that there is no two-fold truth, that is, reason and faith are complementary not in opposition to each other.
1. Natural reason is limited in regards to the knowledge of God.
2. Revelation declares what reason can demonstrate
3. Revelation declares things reason cannot attain by itself alone.
4. Faith assents to the truths of revelation (without reason)
5. Reason gains an (imperfect) understanding of those truths of faith (as demonstrated in 1).
6. Therefore, faith and reason are not opposed to each other because truth is ultimately one.
