One of Augustine of Hippo’s writings which is under-appreciated is his Contra Academicos, which he wrote before his Baptism, though he was preparing to receive Baptism from St. Ambrose, Bishop of Milan, when writing it. As I’m reading through it for a class in Medieval Philosophy, I thought I would just pick out sections where Augustine provides excellent points against skeptics like Carneades. He argues that the skeptic is wrong to say that there is nothing we can know for certain, and provides an interesting list of items which he (Augustine) says we can and do know with absolute certainty.
“For I am sure there is either only one world or more than one. I am also certain that if there is more than one, the number of worlds is either finite or infinite… Another point I know for certain is that the arrangement of our present world stems either from the nature of bodies or is something due to providence. I am also sure it always was and will be, or it had a beginning but will never end, or it never began but will come to an end, or it had a beginning and will eventually cease to be…
For such statements are true in disjunction.
Well your objections will never so prevail over sense experience as to convince us we see nothing at all… For only he errs who rashly accepts appearances as facts.
But note that what I call “world” is this totality, whatever it be, that surrounds and sustains us. I am talking only about what appears to my eyes and seems to contain heaven and earth, or at least what looks like heaven and earth… If you deny that it is the world that appears to me, you make an issue of words, for I have stated that this is precisely what I mean by “world.”
This passage makes Augustine sound like an idealist, but I think it is just a tactical-dialectical move on his part to illustrate the epistemic point he’s driving at.
If the number of worlds be six plus one, it is clear that there are seven worlds no matter how I am disposed. And without being brazen I affirm that I know this. Show me then how sleep or insanity or sense deception make this addition incorrect or the aforesaid disjunctions false.
It is interesting that Augustine thinks we cannot be wrong about simple addition. Descartes thought we could be, since we have experiences of calculating things incorrectly, even with practice, and thus we could be mistaken – but Augustine seems to think we cannot be mistaken about this (and I agree, as I’ve previously argued concerning mathematical propositions).
“But” someone counters, “I am deceived if I give assent.” Restrict your assent to appearances, then, and there will be no deception. I see no way the academician can refute one who says: “I know this looks white to me. I know I like what I hear and enjoy what I smell. I know this tastes sweet to me and that feels cold to me.” “Tell me instead,” says he, “whether the leaves of the wild olive that the goat likes so well are bitter as such.” You rogue! Is the goat that unreasonable? I know not how they taste to cattle, but I find them bitter. What more do you want?
But in the meantime even I, stupid and slow of mind though I be, can know this much about this good in which life’s happiness abides. Either it is to be found in the mind or the body or both or there is no such thing. Convince me, if you can, that I don’t know this.
We (1) exist and (2) know that we do, and this existing and knowing is something we (3) love.
If I am deceived, I exist!
Neither am I in error then in knowing that I know. For just as I know that I am, so too do I know that I know. And when I take delight in these two facts, I add a third and equally important item to what I know, the fact that I love.
Nor am I mistaken that I love when I am not deceived about the things that I love. And even were these false, it would still be true that I love what is false.
The insane man is still alive. The retort to the academician then is not “I know I am not insane,” but “I know that I am alive.”
Whether he be asleep or awake he is alive.
If human knowledge comprised only such things, it would be meager indeed, unless each type were to be multiplied to… [an] infinite [number]. For one who says “I know I live” knows one thing. If he were to add “I know that I know I live,” he knows two things. to recognize they are two is to know a third point. In this way he can add a fourth, a fifth, and countless other items until he has enough… The total number is truly infinite and cannot be comprehended or stated.
If the speaker were to continue: “I know I want this” and “I know I know this fact.” then to these two items he could also add a third, viz., that he knows these two, and a fourth also, viz., that he knows that he knows these two, and so on indefinitely.
There are two types of things one can know; one comprises what the mind perceives with the aid of the bodily senses, the other what it perceives on its own. While the bablings of these philosophers have some relevancy in regard to the former, they are completely powerless to cast doubt on what the mind on its own perceives to be most certainly true, such as the aforementioned “I know that I live.”