We’ve reached the end of Aristotle’s Metaphysics, though there are in fact two more books, Mu (XIII) and Nu (XIV).
Aristotle’s main point of contention with his former colleagues of the Platonic Academy is whether or not mathematical objects and forms understood as universals are independent things in their own right. Both books Mu and Nu (XIV) are concerned with this, and have a somewhat polemical character. I think Aristotle’s own distinctive views on form are better expressed in what has been said already, so I will mostly focus on the other remarks he makes in book Mu, and will skip book Nu entirely.
Book Mu does not clearly refer to the preceding book Lambda (XII), but does refer to previous discussion of “the thinghood that has being as being-at-work” (Sachs tr., ch. 1, p. 253) as well as to discussion on aporias.
“Now it is necessary, if mathematical things are, that they be either in the perceptible things, as some people say, or separate from the perceptible things (and some people also speak of them that way); or if they are not present in either way, then they do not have being or they have it in some other manner. So for us the dispute will not be about whether they have being, but about the manner of their being” (pp. 253-254).
I take especial note of the last sentence above. This could also serve as a comment on what is at stake in the Metaphysics in general — questions not really about being as if it were one thing, but about what things are, and the ways they are.
He goes on to argue that mathematical things are neither “in” perceptible things, nor are they separate things in their own right. “In” for Aristotle suggests a material constituent.
“It has been said sufficiently, then, that mathematical things are not independent things more than bodies are, nor are they prior in being to perceptible things, but only in articulation, nor are they capable of being somewhere as separate; but since they are not capable of being in perceptible things either, it is clear that either they have no being at all, or that they have being in a certain manner and for this reason do not have being simply, for we speak of being in a number of ways” (ch. 2, p. 257).
For those who insist that the whole Metaphysics is a single linear development and not just generally coherent with itself, and also that being finally acquires an unequivocal sense, it seems inconvenient that now, after book Lambda, he continues to emphasize that being is said in many ways.
I think the Metaphysics is very much coherent with itself, but is not a single linear development pointing toward Being, and that he never wavers on the emphasis that being is said in many ways, although he does sometimes use the word equivocally himself. If the whole thing points toward something, that something is the good and the beautiful, and not Being.
He goes on to make some positive remarks about mathematics.
“Now just as the things that are universal within mathematics are not about things that are separate from magnitudes and numbers, but are about these, but not insofar as they are of such a sort as to have magnitude or to be discrete, it is clear that it is also possible for there to be both articulations and demonstrations about perceptible magnitudes, not insofar as they are perceptible but insofar as they are of certain sorts” (ch. 3, p. 257).
He is saying that insofar as there is mathematical knowledge, it is not about magnitude or number as such, but about more specific things such as right triangles or even numbers. Similarly, the meaning of articulations and demonstrations about perceptible magnitudes does not depend on their perceptibility as such.
“[S]ince it is true to say simply that there are not only separate things but also things that are not separate…, it is also true to say simply that there are mathematical things and that they are of such a sort as people say….If it is about things which incidentally are perceptible, but is not concerned with them insofar as they are perceptible, mathematical knowledge will not be about perceptible things; however, it will not be about other separate beings besides these either” (p. 258).
Mathematical things are bona fide things in the broad sense, but not all things are separate or independent. Some are attributed to others.
“[I]f someone examines anything concerning these attributes, insofar as they are such, positing them to be separate, he will not on this account cause anything to be false, any more than when one draws a line on the ground that is not a foot long, and says it is a foot long, for the false assumption is not in the proposition…. [F]or this reason the geometers speak rightly” (pp. 258-259).
Mistaken belief about the independence of mathematical things is incidental to the doing of mathematics. It is irrelevant to the results of constructions or calculations.
“And since the good and the beautiful are different (for the former is always involved in action but the beautiful is also present in motionless things), those who claim that the mathematical kinds of knowledge say nothing about what is beautiful and good are wrong…. The greatest forms of the beautiful are order and symmetry and determinateness, which the mathematical kinds of knowledge most of all display. And since these make their appearance as causes of many things…, it is clear that these kinds of knowledge would also speak about what has responsibility in the manner of the beautiful as a cause in some manner” (p. 259).
Here he not only recognizes mathematical beauty, but relates it to the beauty associated with that-for-the-sake-of-which as a cause.
“The opinion about the forms came to those who spoke about them as a result of being persuaded by the Heraclitean writings that it is true that all perceptible things are always in flux, so that, if knowledge and thought are to be about anything, there must be, besides the perceptible things, some other enduring natures, since there can be no knowledge of things in flux. And then Socrates made it his business to be concerned with the moral virtues, and on account of them first sought to define things in a universal way. For among those who studied nature, only to a small extent did Democritus attain to this… and before that the Pythagoreans did about some few things…. But it is reasonable that Socrates sought after what something is…. But Socrates did not make the universals or the definitions separate, while those who came next did, and called beings of this sort forms” (ch. 4, p. 260).
Aristotle rejects the Heraclitean doctrine of radical flux that influenced Plato. He says Plato was driven to assert separate forms because he wanted to assert that there is knowledge, in spite of his Heracliteanism about perceptible things. Aristotle says that driven by a concern for ethics, Socrates — and not any of those we know as the pre-Socratics — was the first to seriously inquire about what things are. Aristotle has been inquiring about the what-it-is of things and its causes and sources, and we have seen in abundance his concern for the good and the beautiful. Aristotle is claiming a Socratic heritage, and claiming to be truer to it than the Platonists: “Socrates did not make the universals or the definitions separate”.
There follows a long argument against Platonic views about the forms, at the end of which he observes:
“[K]nowledge, like knowing, has two senses, the one as in potency, the other as at-work. The potency, being, like material, universal and indeterminate, is of what is universal and indeterminate, but the being-at-work is determinate and of something determinate; being a this it is of a this, but incidentally sight sees a universal color because this color that it sees is a color, and this A that the grammarian contemplates is an A” (ch. 10, p. 279).
If I am reading this right, he is saying here that being as universal and indeterminate is to being-at-work as potentiality is to being-at-work. If that is so, then the priority of actuality over potentiality would also seem to be a priority of actuality over being. Once again, it just doesn’t seem that being is the principal term.
In any case, he returns to the ultimately ethical theme of the priority of actuality or being-at-work or fulfillment over potentiality, and of particular concrete things over universals in the ordinary logical sense. This still has to be carefully balanced with his other view that there is no knowledge of particulars; knowledge is of universals only.
Positive concern for the priority of actuality is in my opinion the primary thing that underlies his sharp critique of the Platonists. The second — evidenced in the part I skipped over — was the popularity within the Academy of a kind of Pythagorean mystique of numbers that also identified the forms with numbers, in sometimes baffling ways. Plato himself was apparently not immune to this.
Many think Aristotle claims to have knowledge of non-perceptible particular independent everlasting things. I think this interpretation relies on ambiguous use of Aristotle’s saying of “knowledge” in different ways in different contexts. Sometimes he means it very strictly, other times much more loosely. Some translations add confusion by using the same English “knowledge” for other Greek words like gnosis, which I think for Aristotle means personal acquaintance with things nearer to us, whereas episteme is supposed to be about things in their own right.
I do not think that Aristotle means to claim knowledge in the strong sense about ultimate things, but rather that his attitude was in a way closer to that of Kant, who held them to have the highest importance but not to be knowable in the strict sense. This means we do not have to equivocate about what knowledge is.
The wisdom that is called sophia in book capital Alpha initially seems to be concerned with universals in the ordinary sense, as true episteme or knowledge genuinely is. It turns out in book Lambda that sophia‘s primary concern is not with universals in the ordinary sense at all, but with analogous relations that a uniquely positioned particular or particulars has or have to all other things.
In any case, my own view is that the wisdom or sophia concerning these highest things ought to be understood as aligned not so much with knowledge or episteme, as with the ethical or “practical” wisdom (phronesis) that is explicitly said to be a wisdom about particulars. A wisdom about particulars is not prevented from making — and indeed presumably would make — use of knowledge of any universals that genuinely apply. Nonetheless it is the wisdom about particulars that judges which universals should apply in a particular case.