Commentary Aristotle Posterior Analytics
He sets down the third grade, at: and when such persistence (101a1), saying that, when there are many such animals who have memory, there is finally a certain difference among them: for in certain ones there is ratiocination of what remains in the memory, as happens in men, but in others there is not, as happens in beasts.
Then, at: so out of sense-perception (101a4) he shows, in view of the foregoing, how the knowledge of first principles comes about in us.
He concludes from the foregoing that from sensing comes remembrance in those animals in which a sensible impression remains, as has been stated above. But from remembrance many times repeated in regard to the same item but in diverse singulars arises experience, because experience seems to be nothing else than to take something from many things retained in the memory.
However, experience requires some reasoning about the particulars, in that one is compared to another: and this is peculiar to reason. Thus, when one recalls that such a herb cured several men of fever, there is said to be experience that such a herb cures fevers. But reason does not stop at the experience gathered from particulars, but from many particulars in which it has been experienced, it takes one common item which is consolidated in the mind and considers it without considering any of the singulars. This common item reason takes as a principle of art and science. For example, as long as a doctor considered that this herb cured Socrates of fever, and Plato and many other individual men, it is experience; but when his considerations arise to the fact that such a species of herb heals a fever absolutely, this is taken as a rule of the art of medicine.
This, then, is what he means when he says that just as from memory is formed experience, so from experience or even from the universal resting in the mind (which, namely, is taken as if it is so in all cases, just as experience is taken as being so in certain cases). This universal is said to be resting in the mind, inasmuch as it is considered outside the singulars, which undergo change.
Furthermore, he says that it is one outside the many, not according to an autonomous existence but according to the consideration of the intellect which considers a nature, say of man, without referring to Socrates and Plato.
But even though it is one outside the many according to the intellect’s consideration, nevertheless in the sphere of existents it exists in all singulars one and the same: not numerically, however, as though the humanity of all men were numerically one, but according to the notion of the species. For just as this white is similar to that white in whiteness, not as though there were one numerical whiteness existing in the two, so too Socrates is similar to Plato in humanity, but not as though there were numerically one humanity existing in the two.
Therefore, from this experience and from such things universally taken from experience, the principle of art and science is formed in the mind.
And he distinguishes between art and science, just as he did in Ethics VI, where it is stated that art is right reason in regard to things to be made. And so he says here that if from experience a universal in regard to generation is taken, that is, in regard to anything that can be made, say in regard to healing or husbandry, this pertains to art. Science, however, as it is stated in the same place, is concerned with necessary things; hence if the universal bears on things which are always in the same way, it pertains to science; for example, if it bears on numbers or figures.
And this process which has been described is verified in regard to the principle of all sciences and arts. Hence he concludes that there do not preexist any habits of principles in the sense of being determinate and complete, neither do they come to exist anew from other better known preexisting principles in the way that a scientific habit is generated in us from previously known principles; rather the habits of principles come to exist in us from preexisting sense.
And he gives as an example a battle which starts after the soldiers have been beaten and put to flight. For when one of the soldiers shall have taken a stand, that is, begun to take a battle position and not flee, another takes his stand next to him, and then another, until enough are gathered to form the beginning of a battle. So, too, from the sense and memory of one particular and then of another and another, something is finally reached which is the principle of art and science, as has been stated.
But someone could believe that sense alone or the mere remembrance of singulars is sufficient to cause intellectual knowledge of principles, as some of the ancients supposed, who did not discriminate between sense and intellect. Therefore, to exclude this the Philosopher adds that along with sense it is necessary to presuppose such a nature of mind as cannot only suffer this (that is, be susceptible of universal knowledge, which indeed comes to pass in virtue of the possible intellect) but can also cause this in virtue of the agent intellect which makes things intelligible in act by abstraction of universals from singulars.
Then, at: let us now restate (101a14) he elucidates something asserted in the preceding solution, namely, that the universal is taken from experience bearing on singulars.
And he says that what was stated above, albeit not clearly—namely, how from the experience of singulars the universal is formed in the mind—must now be discussed again and explained more clearly. For if many singulars are taken which are without differences as to some one item existing in them, that one item according to which they are not different, once it is received in the mind, is the first universal, no matter what it may be, that is, whether it pertains to the essence of the singulars or not. For since we find that Socrates and Plato and many others are without difference as to whiteness, we take this one item, namely, white, as a universal which is an accident. Similarly, because we find that Socrates and Plato and the others are not different as to rationality, this one item in which they do not differ, namely, rational, we take as a universal which is an essential difference.
But how this one item can be taken he now explains. For it is clear that sensing is properly and per se of the singular, but yet there is somehow even a sensing of the universal. For sense knows Callias not only inasmuch as he is Callias, but also as he is this man; and similarly Socrates, as he is this man. As a result of such an attainment preexisting in the sense, the intellective soul can consider man in both. But if it were in the very nature of things that sense could apprehend only that which pertains to particularity, and along with this could in no wise apprehend the nature in the particular, it would not be possible for universal knowledge to be caused in us from sense-apprehension.
Then he manifests this same point in the process which goes from species to genus. Hence he adds: again in these, namely, in man and horse, “the mind lingers in its consideration, until it attains to some thing indivisible in them, which is universal.” For example, we consider such an animal and another one, say a man and a horse, until we arrive at the common item, “animal,” which is universal; and in this genus we do the same until we arrive at some higher genus.
Therefore, since we take a knowledge of universals from singulars, he concludes that it is obviously necessary to acquire the first universal principles by induction. For that is the way, that is, by way of induction, that the sense introduces the universal into the mind, inasmuch as all the singulars are considered.
Then, at: now, of the thinking states (101b5) he solves the first two questions, namely, whether the knowledge of first principles is science, or some other habit.
In regard to this he accepts, from what has been stated above, that the knowledge of principles pertains to the intellect whose function is to know the universal: for he says that the universal is a principle of science. But in regard to the intellect there are two genera of habits, and these are not related to the true in exactly the same way. For some are always true, whereas others sometimes receive what is false, as in opinion and in those cases of reasoning which can be of the true and of the false. Again, there are certain erroneous habits, namely, which bear on the false. But because principles are most true, it is clear that they do not pertain to habits which are always of the false, or even to habits which now and then receive falsity, but only to habits which are always of the true. But these are science and understanding [that is, intuition]. (In Ethics VI a third one is added, namely, wisdom: but because wisdom, as it is stated there, comprehends within itself both science and understanding—since it is a science and the chief of the sciences—he omits it here). Therefore, leaving this one aside, no other genus of knowledge but understanding is more certain than science.
Now, it is plain that the principles of demonstrations are better known than the demonstrated conclusions, as was established in Book I. Moreover, it cannot be through science that we have those principles, because science is the result of reasoning, namely, demonstrative, whose principles are the very things about which we are speaking. Therefore, because nothing can be truer than science and understanding (for wisdom is included in them), what follows from our consideration of the foregoing is that, properly speaking, the knowledge of principles is understanding.
He also proves this with another reason, namely, because a demonstration is not of necessity a principle of a demonstration; otherwise there would be an infinite process in demonstrations, and this was disproved in Book I. Since, therefore, demonstration causes science, it follows that neither can science be the principle of science, as though the principles of the sciences were made known through science. Therefore, if we have no other type of knowledge except science which is always true, it follows that understanding will be the principle of science, namely, because the principles of the sciences are made known through understanding, so far forth, namely, that this understanding which is the principle of science is cognoscitive of the principles from which science proceeds. But this, namely, science, is all, that is, a whole, which is related to every thing (that is, to the entire matter with which science is concerned) in the way that understanding is related to the principles of science.
And with this ends the exposition of Aristotle’s Posterior Analytics, to the honor of Christ, who is God, blessed in eternity. Amen.