Ordinatio

First. These reasons [nn.211-213] seem to prove the impossibility of natural certain knowledge. The first because if the object is ceaselessly changing, neither is it possible for any certitude to be had of it under the idea of the changeless, indeed nor could certitude be had of it in any light whatever, because there is no certitude when the object is known in a way other than it is. Therefore, neither is there certitude in knowing the changeable as unchangeable. It is plain too that the antecedent of this reason, namely that sensibles are ceaselessly changing, is false; for this is the option that is imputed to Heraclitus in Metaphysics 4 [4.5.1010a7-11].

Likewise if, because of the changeableness of the exemplar, what is in our soul could not be certitude [n.212], since whatever is put subjectively in the soul is changeable (even the very act of understanding), it follows that by nothing in the soul is the soul put right so as not to err.¹

Similarly, according to this opinion the inhering created species concurs with the inflowing species [n.217]. But when something concurs that is repugnant to certitude, certitude cannot be had. For just as from a proposition about the necesssary and a proposition about the contingent only a proposition about the contingent follows, so from something certain and something uncertain, concurring for some knowledge, no certain knowledge follows.

The same is plain also about the third reason [n.213], because if the very species abstracted from the thing concurs for every cognition, and no judgement can be made as to when the species represents itself as itself and when it represents itself as the object, then, whatever else concurs, no certitude can be had by which the true may be discriminated from the likely. These reasons, therefore, seem to prove the whole incertitude and opinion of the Academics.

And that this conclusion [n.222] is not Augustine’s intention I give proof: Augustine Soliloquies 1.8 n.15, “Everyone concedes without any doubt that the proofs of the sciences are most true.” And Boethius On the Hebdomads, “A common conception of the mind is what each approves when it is heard.” And the Philosopher in Metaphysics 2.1.993b4-5, “First principles are known to everyone like a door to a house, because as a door is open to view, though the interior of the house is not, so are the first principles known to everyone.”

From these three authorities [n.223] the argument goes as follows. What belongs to everything of some species follows the specific nature. Therefore, when each has infallible certitude of the first principles, and further to anyone at all the form of a perfect syllogism is naturally evident (from the definition of a perfect syllogism in Prior Analytics 1.1.24b22-24), but the science of the conclusions depends only on the evidence of the principle and the evidence of the syllogistic inference – therefore to anyone at all can naturally be known any conclusion at all demonstrable from self-evident principles.

Second it is clear that Augustine concedes the certainty of the things that are known by sense experience; hence he says On the Trinity 15.12 n.21, “Far be it that we should doubt to be true what we have learnt through the senses of the body; indeed through them we have learnt heaven and earth and sea and all that is in them.” If we do not doubt of the truth of them, and we are not deceived, as is plain, then we are certain of things known by way of the senses; for certitude is had when doubt and deception are excluded.

It is also plain, third, that Augustine concedes certitude of our acts, ibid., “Whether one sleeps or is awake, one lives, because both to sleep and to see in dreams belong to him who is alive.”

But if you say that ‘to live’ is not second act but first act, there follows ibid., “If someone say I know that I know I am alive, he cannot be deceived,” even when reflecting however often on the first thing known [sc. ‘I know that…’]. And ibid., “If someone say ‘I want to be blessed’, how is it not impudent to reply, ‘perhaps you are deceived?’,” and by reflecting there “the ‘I know I want’ endlessly etc.” Ibid., “If anyone say, ‘I do not wish to err’, will it not surely be true that he does not want to err?” “And other things,” he says, “are found that avail against the academics, who contend that nothing can be known by man.” There follows ibid., about the three books Against the Academics, “he who has understood those books will be moved not at all against the perception of truth by their many arguments.”

Again, ibid. ch.15 n.25, “Things that are so known that they could never be lost also belong to the nature of the soul itself, of which sort is that we know we live.”² So the first point is plain [n.218].³