It is an existential fact that man is conceived and born under a natural order of things — except the case of Jesus Christ who was conceived through the Holy Spirit, and thus under both the supernatural (necessarily) and natural (contingently) order of things.
It is a plain fact that man is born without knowledge in him. As to factual reality, St. Thomas Aquinas (1225-1274 AD) says, contra factum non argumentum est (against fact there is no argument).
Man needs to acquire knowledge through schooling and/or life experience.
How can this phenomenon be accounted for? How does man come to know?
There are theories that would answer such questions. Let’s take the theories in ancient Greece. First, Aristotle (384-322 BC) posits the idea that all knowledge begins with sense perception. Here the five senses are the means to know the physical world. Aquinas follows Aristotle’s notion, which is a reaction to the teaching of his teacher, Plato (427/428-347/348 BC), on this subject.
Second, Plato posits his theory of reminiscence (Meno). For him man is composed of body and soul. The soul is encapsulated within man’s body during conception. Prior to conception (or encapsulation), the soul possesses knowledge (there in the ideal world of Forms), but during conception, that knowledge is lost. Thus, man has in fact no knowledge from the moment of conception or encapsulation. Man needs to acquire such lost knowledge, a sort of reminiscing. Plato’s notion of education must have been based on this existential fact.
(However, supposing Plato is right, it is not clear whether or not he conceived of knowledge as pre-given along with the being of the soul itself separately, prior to the encapsulation within the human body. But I am in the opinion that, even in the world of Forms, knowledge is not something pre-given along with the being of the soul. Knowledge is still to be acquired by the soul in a direct way since there is no involvement of the human senses.)
What happens after Plato and Aristotle? It is not far-fetched to see that it is either Plato’s or Aristotle’s theory that dominates as an account of how man acquires knowledge (let alone other theories of other philosophers). But, a reflection on this subject would show that it is not an “either-or” but a “both-and” situation.
On the one hand, Plato’s conception of the world of Forms cannot be entirely dismissed for a complete acceptance of Aristotle’s theory. Neither Aristotle’s theory be dismissed for a complete acceptance of Plato’s theory.
Later, St. Augustine of Hippo (354-430 AD), accepting Plato’s Allegory of the Cave and the Form of the Good, posits his theory of Divine Illumination, which holds that man’s mind needs divine illumination so that it can grasp eternal, immutable truths. This idea suggests that knowledge can be directly infused into the mind without passing through the senses.
And it appears that it is no longer by the power of man’s mind itself but by the power of God himself. In other words, God (and in fact God alone) can directly infuse knowledge into the mind, bypassing man’s sensory organs. Can God do this? Yes, absolutely!
On the other hand, Aristotle’s theory of knowledge is true. It is in accord with the natural order of things. Naturally, man comes to know the physical world through the senses. For how else can man come to know the world except through the senses?
Later, Aquinas continues with the Aristotelian tradition, affirming that nothing comes to the mind unless it passes through the senses. And it is an existential fact. Even the abstract realties of pure mathematics somehow get their origin from previous sense experience.
In the modern period (beginning around 1500, the early modern period), the French philosopher Rene Descartes (1596-1650 AD) holds on to Rationalism, which says that reason is the primary source, justification and test of true knowledge. The English philosopher David Hume (1711-1776 AD) holds on to Empiricism, which says that sense experience, observation, experimentation is the true source of knowledge. It is the modern expression of the old debate between Platonic and Aristotelian traditions.
How, then, are we to weigh this subject matter? Are/is Plato’s, St. Augustine’s and/or Descartes’ views the only true account of how man comes to know something? Or, are/is Aristotle’s, Aquinas’ and/or Hume’s views the only true account of the same thing? I would like to reiterate that it is not an “either-or” but a “both-and” situation.
Now, as to the possibility of man to come to know something, there can be two ways. First, it is possible for man to come to know something, such as eternal truths, in the world of Forms (Plato) by way of direct Divine Illumination (St. Augustine) by the action of God himself. I don’t think it is metaphysically impossible. Second, it is natural for man to come to know something of this physical world through the five sensory organs. It is within man’s natural capacity to know this way.
But, for either side — Plato-Augustine-Descartes or Aristotle-Aquinas-Hume — to claim as the only true account is to fall into reductionism. The way of knowing is reduced to either side only, to the exclusion of the other and vice versa. (So Kant (1724-1804 AD) tried to solve this dilemma). But, as the immaterial soul is true, it is possible for it to come to know eternal truths by direct infusion, as in St. Augustine’s divine illumination. And, as the physical world is true, it is possible also for man to come to know through the sensory organs.
My stance on this subject is that both sides — Plato-St. Augustine-Descartes, on the one hand, and Aristotle-Aquinas-Hume, on the other hand — are true and correct but not absolutely and that no side can claim to be the exclusive account of how man comes to know. They are not supposed to be competing but complementing, on the ground of the realities of both body and soul.