In an earlier post (go here) I gave a brief overview of St. Augustine’s (354-430 C.E.) argument for God’s existence from eternal truth in his dialogue On Free Choice of the Will (Macmillan, 1964). Augustine argues that our minds can know truths that are eternal. For Augustine, something is eternal if it exists in a timeless, unchanging state. So eternal truths are unchanging and are not in, or influenced by, time. For example, consider the following three propositions:
- A cannot be both B and not B at the same time and the same respect (the law of non-contradiction)
- Either A or not A (the law of excluded middle)
Augustine would claim that these propositions are eternal truths. This means their truth never changes and is not dependent on any event in the past, present, or future. These truths hold for everyone, everywhere, at all times. To be sure, changing beings can think these truths in time and they can be represented in various languages and sentences that change. But the truths themselves never change.
Now ask yourself: could human minds produce eternal truths? Well, if eternal truth exists then it is unchanging. But human minds are always changing. So eternal truth cannot be a product of our minds. Augustine writes: “If truth were equal to our minds, it would be subject to change. Our minds sometimes see more and sometimes less, and because of this we acknowledge that they are mutable. Truth, remaining in itself, does not gain anything when we see it, or lose anything when we do not see it” (67). We could also add that there was a time when humans did not exist. So eternal truths, as always existing, cannot possibility be the product of our minds. But if human minds didn’t produce eternal truth then what did? Well, nothing produces eternal truth because, being eternal, it always exists. But perhaps some mind, rather than producing eternal truths, always has eternal truths in mind. Such a mind would have to be eternal itself if the truths it possesses are eternal. Augustine thinks this line of reasoning strongly suggests an eternal being exists who sustains eternal truths.
But Augustine goes further and argues that without God we wouldn’t be able to know eternal truth. To explain how the human mind knows eternal truths Augustine presents a theory of divine illumination. Kenneth Shouler, in his Stanford Encyclopedia of Philosophy entry “Divine Illumination”, writes:
“There is present in us the light of eternal reason, in which light the immutable truths are seen,” he wrote. For Augustine, this illumination comes from God, just as light comes from the sun….He believed that the divine light is to the mind as the sun is to the eyes — a metaphor straight out of Plato’s allegory of the cave. Every human mind needs God’s light to uncover the forms or to see the truth. If a person thinks she has discovered this on her own, she simply misunderstood the source of their light.”
Shouler formalizes Augustine’s argument as follows:
Premise 1: Persons have ideas of eternal truths.
Premise 2: They could not have arrived at these truths on their own.
Therefore, to arrive at these truths they need the illumination that comes from God.
In On Free Choice of the Will, Augustine argues for the existence of this illumination or “inner light” with reference to a mathematical rule that can be immediately grasped:
“In observing the order of numbers, we see after one the number two, which is twice one. Twice two does not follow next in order; rather, three comes next, and then four, which is twice two. This order continues throughout all the rest of the numbers by a fixed and unchangeable law….Through all the rest of the numbers you will find the same thing that is found in the first pair of numbers, one and two, namely, the double of any number is as many times after this number as such a number is from the beginning….How do we discern that this fact which holds for the whole number series is unchangeable, fixed, and incorruptible? No one perceives all the numbers by any bodily sense, for they are innumerable. How do we know that this is true for all the numbers? Through what fantasy or vision do we discern so confidently the firm truth of number throughout the whole innumerable series, unless by some inner light unknown to bodily sense?” (56, my italics).
We seem to be able to grasp, in a moment of insight, that a particular pattern that holds for a small set of numbers will hold for all numbers. We see that 5 x 2 = 10 and that 5 is as many places away from 10 as 5 is from 1. We see this instance and then we know it will hold for all numbers in the series. But how? We don’t reach our knowledge regarding the extent of the pattern based on (1) a calculation made by our mind since our mind is finite and the pattern is presumably infinite; nor on (2) sense experience since, on the one hand, numbers don’t seem to be physical things and, on the other hand, we certainly don’t see the whole series of numbers in front of us. For Augustine it is the divine illumination, neither a light of the physical world nor a light of the human mind, which gives us both the eternally true content we know, in this case the mathematical rule, and the justification for the rule’s truth in the form of an immediate intuition, that is, an intuition that is not the result of an inference. Robert Pasnau explains:
“To speak of…illumination is of course to use a metaphor, one not likely to be unpacked fully. Our own minds present enough of a puzzle to us: when we try to understand how the divine mind might influence our own, we must inevitably fall back on metaphor. Still, there are a variety of ways in which we might seek some clarification. In particular, it is helpful to distinguish two ways in which God might provide illumination. First, he might simply give us information of certain kinds, telling us how things are. This is how illumination is most often understood, at least implicitly. But a second possibility is that God would provide not the information itself, but the insight into the truth of the information. On this second model, we would frame beliefs on our own, and God would illuminate our minds so that we could see the truth. In other words, God would supply the justification. It is clear that sometimes illumination takes the first form: much of Biblical revelation just is illumination in this sense. But Augustine’s theory of illumination seems largely to be of the second kind.” (SEP, “Divine illumination”)
As mentioned above, this account has similarities to Plato’s account of the Good in his dialogue Republic (go here for my overview of the Good). Socrates speculates that, just as the sun in our world both enables things to be seen and sustains the being of those things with its energy, the Form of the Good both sustains the unchanging Forms in the intelligible realm and grants our soul the ability to perceive them. Moreover, the Good’s power carries over into the physical world as well: it sustains the sun which is an image of itself. Augustine was profoundly influenced by Plato but, of course, wanted to transform many of Plato’s ideas in light of his Christian commitments. In this case we seem to have a nice example of such a transformation: Plato’s Form of the Good becomes God. David Bentley Hart, in his book The Experience of God, elaborates:
“One should recall the entire point of Plato’s inquiry in the Euthyphro was to show that there must be some eternal principle – which he would call the Form of the Good – beyond the realm of either material natural or limited willful deities. This is all part of an ancient metaphysical project going alll the way back to Xenophanes, which is the common heritage of philosophy and rational theology alike….For all the great monotheisms, God is himself the Good, or the Form of the Good, and his freedom consists in his limitless power to express his nature (goodness) unhindered by the obstacles or limitations suffered by finite beings. He is “the love that moves the sun and all the other stars,” as Dante phrases it, at once the underlying unity and the final end of all things.” (275-6)
God, like Plato’s Form of Good, moves the sun. But he does so by love and illuminates our soul in ways that “the absolute nature of that love is reflected in the unconditional quality of the transcendental or ecstatic nature it excites in rational natures.” (276).