Aristotle: Is “Non-feathered” a Genus of Animals?

In the last post I primarily addressed Aristotle’s objection to dichotomous division, a taxonomic method that Platonists used to determine the kinds of animals there are and where any particular animal kind fits, an enterprise roughly equivalent to the animal-classification that for contemporary biology results in the designation of genus and species.  In particular, amongst Aristotle’s objections to dichotomous division, he says that grouping birds into, say, feathered and non-feathered, results in the absurdity that the latter does not exist

And yet it is necessary to divide by privation, and the dichotomists do divide [in this way].  But there is no difference of a privation qua privation.  For it is impossible for there to be species of what is not, for example of “non-footed” or of “non-winged” just as there are species of “footed” and “winged.”  Furthermore it is necessary that species belong to a generic difference.  For if they do not, why would they belong to a generic difference and not a specific difference? (Aristotle, Parts of Animals, 642b21-26).(1)

The objection substantively amounts to this: because a privation does not exist, e.g. “non-winged,” there cannot be any species subsequently derived from it.  And, as the concluding question makes clear, if in fact no pair of species can be divided from it, then this means that, e.g. “non-winged,” is a species.  This is evidently false, however, because “non-winged” is as indeterminate a species for ancient taxonomy as it would be for modern biology.

However, what if Platonists appealed to Aristotelian privation in making a case for dividing privation?   In his Physics Aristotle says this:

But white comes to be from the non-white, and not from everything [that happens to be non-white] but from black or from something between black and white, and an educated man comes to be from something that is not educated, but not just from anything that is not educated, but rather from an uneducated man, unless this happens incidentally.  Again the white turns into the non-white, and not into the chance non-white but into the black or an intermediate (Physics 188a36-188b6). (2)

Now Aristotle is clearly, in context, discussing how things come to be, and more particularly how this generation comes about from opposites.  A black beard, for example, comes to be white, where this whiteness is explicable by saying it comes to be from “non-white,” yet not just any non-white (as say, the number 1 is non-white), but from the opposite of white, black, or an intermediate, gray.

Nevertheless it seems plausible that this concept of privation, although employed to a very different purpose in the Physics than in our taxonomic concerns, establishes that we can use privation as a faithful ontological characterization of things.  If that is the case, there is no reason we cannot use “non-feathered” as a genus from which we can further dilineate more species.

Would Aristotle accept this understanding of privation from Physics for his work on animal classification?

More broadly, does this eliminate Aristotle’s original objection to privation as a method of division?

(1)
Translation mine:
Ἔτι στερήσει μὲν ἀναγκαῖον διαιρεῖν, καὶ διαιροῦσιν οἱ
διχοτομοῦντες. Οὐκ ἔστι δὲ διαφορὰ στερήσεως ᾗ στέρησις·
ἀδύνατον γὰρ εἴδη εἶναι τοῦ μὴ ὄντος, οἷον τῆς ἀποδίας ἢ τοῦ
ἀπτέρου ὥσπερ πτερώσεως καὶ ποδῶν. Δεῖ δὲ τῆς καθόλου δια-
φορᾶς εἴδη εἶναι· εἰ γὰρ μὴ ἔσται, διὰ τί ἂν εἴη τῶν καθόλου
καὶ οὐ τῶν καθ’ ἕκαστον;

(2)
Translation mine:
ἀλλὰ λευκὸν μὲν γίγνεται ἐξ οὐ λευκοῦ, καὶ τούτου οὐκ ἐκ παντὸς
ἀλλ’ ἐκ μέλανος ἢ τῶν μεταξύ, καὶ μουσικὸν οὐκ ἐκ μου-
σικοῦ, πλὴν οὐκ ἐκ παντὸς ἀλλ’ ἐξ ἀμούσου ἢ εἴ τι αὐτῶν
ἐστι μεταξύ. οὐδὲ δὴ φθείρεται εἰς τὸ τυχὸν πρῶτον, οἷον
τὸ λευκὸν οὐκ εἰς τὸ μουσικόν, πλὴν εἰ μή ποτε κατὰ συμ-
βεβηκός, ἀλλ’ εἰς τὸ μὴ λευκόν, καὶ οὐκ εἰς τὸ τυχὸν ἀλλ’
εἰς τὸ μέλαν ἢ τὸ μεταξύ·

Aristotle’s Categories: Predication with Genus and Differentiae

(See here for the previous posts on the Categories: Chapter 1, Chapter 2)

Aristotle’s philosophical writing, often opaque in style as well as content, can also venture into extended periods of intricate simplicity, innovating complexity and depth from a rather limited set of fixed, technical terms.  This is the case for much of the Categories, and chapter 3 certainly fits this description as well.  In this post, I will be continuing my quasi-commentary on Aristotle’s Categories, now arriving at chapter 3.

Whenever one thing is predicated of another as of a subject (ὑποκειμένου), as many things as are said of the thing being predicated, all of these will also be said of the subject. For example human is predicated of an individual human, and animal is predicated of a human. Therefore animal will be predicated of an individual human also. For an individual human is both a human and an animal.

 

Of the things differing in genus and not being subordinated to one another there are differentiae different in kind (τῷ εἴδει), for example, there are [distinct] differentiae of animal and of knowledge: footed, winged, water-dwelling, two-footed, and none of these is [a differentia] of knowledge. For [one kind] of knowledge does not differ from [another] knowledge by having two feet. Yet nothing prevents there being the same differentiae of the genera subordinate to each other. For the higher genera are predicated of the things said under them, so that as many differentiae as there are of the thing being predicated there will be of the subject as well (Translation mine, Categories 1b10-24). [1]

Aristotle begins this section with the confusingly worded, “Whenever one thing is predicated of another as of a subject (ὑποκειμένου), as many things as are said of the thing being predicated, all of these will also be said of the subject.”  Now the example that follows makes the concept he is addressing here rather clear.  If an individual human is a human, and if a human is an animal, then an individual human is an animal.  In this instance, using Aristotle’s terminology, the subject and the thing being predicated of is “the individual human,” while the thing being predicated is “human.”  (Keep in mind that I use quotation marks not to designate a mere linguistic term, but to clarify and distinguish the objects to which they refer.)

Aristotle next invokes language about genus and differentia (plural, genera and differentiae.)  Assuming that there are such entities we may roughly think of as “kinds of things,” designated as genera, then it follows that these things must be organized and distinguished from each other in some way.  For example, taking animal as a real genus, we can say that there are (at least) two “kinds”: birds and fish.  These two kinds of things, birds and fish, are each a species of the genus animal, and although they belong to the genus animal, birds and fish are distinguished from each other by differing in some salient way.  Possession of this differing property or properties, such as scales or feathers, is what makes the one animal (fish) differ from the other (bird).  Thus these properties are called differentiae.  Since this usage of genus is not to be confused with our modern classifications in biological nomenclature, we can freely apply the term genus to whatever level of kinds of things we wish.  With confidence in being philosophically consistent, in other words, we can also say that in addition to animal, fish is also a genus, with the differentiae of salt-water or fresh-water picking out two other species based on the difference of the type of water inhabited.  What Aristotle warns against in the second half of this text is being sloppy when it comes to distinctions made in one genus that do not apply to another, viz. knowledge and animal, where one applies two-footedness to knowledge.


 

REFERENCES:

[1] Ὅταν ἕτερον καθ’ ἑτέρου κατηγορῆται ὡς καθ’ ὑποκει- (10)
μένου, ὅσα κατὰ τοῦ κατηγορουμένου λέγεται, πάντα καὶ κατὰ τοῦ ὑποκειμένου ῥηθήσεται· οἷον ἄνθρωπος κατὰ τοῦ τι-
νὸς ἀνθρώπου κατηγορεῖται, τὸ δὲ ζῷον κατὰ τοῦ ἀνθρώπου·
οὐκοῦν καὶ κατὰ τοῦ τινὸς ἀνθρώπου τὸ ζῷον κατηγορηθήσε-
ται· ὁ γὰρ τὶς ἄνθρωπος καὶ ἄνθρωπός ἐστι καὶ ζῷον. (15)
τῶν ἑτερογενῶν καὶ μὴ ὑπ’ ἄλληλα τεταγμένων ἕτεραι
τῷ εἴδει καὶ αἱ διαφοραί, οἷον ζῴου καὶ ἐπιστήμης·
ζῴου μὲν γὰρ διαφοραὶ τό τε πεζὸν καὶ τὸ πτηνὸν καὶ τὸ
ἔνυδρον καὶ τὸ δίπουν, ἐπιστήμης δὲ οὐδεμία τούτων· οὐ γὰρ
διαφέρει ἐπιστήμη ἐπιστήμης τῷ δίπους εἶναι. τῶν δέ γε (20)
ὑπ’ ἄλληλα γενῶν οὐδὲν κωλύει τὰς αὐτὰς διαφορὰς εἶναι·
τὰ γὰρ ἐπάνω τῶν ὑπ’ αὐτὰ γενῶν κατηγορεῖται, ὥστε
ὅσαι τοῦ κατηγορουμένου διαφοραί εἰσι τοσαῦται καὶ τοῦ
ὑποκειμένου ἔσονται.

Aristotle’s Essence: τὸ τί ἦν εἶναι

τὸ τί ἦν εἶναι is an odd phrase, common to Aristotelian diction, used when the philosopher wishes to speak about the essence of a particular thing. Most students translate the phrase as “essence” by rote, because they have not the faintest conception on how to penetrate the meaning of this four-word hieroglyphic.

Let us begin by discussing what this construction consists of at its most basic level. Fundamentally the phrase is an articular infinitive. Dr. Smyth tells us that, “The articular infinitive, while having the character of a substantive, retains the functions of a verb” (See Smyth, 2025 and following). The “character” of a substantive means that we are able to decline the infinitive as a neuter singular noun, if we place the appropriately declined definite article (τό, τοῦ, τῷ, τό) in front of it. Thus, τὸ ποιεῖν can be translated not merely as “to make,” but also as “making.” With this in mind, τὸ εἶναι, is “to be” or “being,” often simplified by most translators to “essence.”

This leaves us with the two inner terms, τί ἦν. First let us look at the imperfect ἦν. In Smyth 1901-1902 we are told that the imperfect can be used for the present tense. Liddell and Scott (εἰμί F. bottom of entry) inform us that ἦν is sometimes used as the present, corroborating the account given by Smyth. Liddell and Scott also make mention of Aristotle’s exact phrase, remarking that, “τὸ τί ἦν εἶναι expresses the essential nature of a thing.” Thus the ἦν is actually an ἐστί, at least for translation purposes.

The LSJ entry is further helpful in determining the meaning of τί ἦν as a two-word phrase. It points out that τί ἦν, in the phrase τὸ τί ἦν εἶναι, takes the place of a very similar articular infinitive, but with a dative phrase, such as τὸ ἀγαθῷ εἶναι, which can be seen in Prior Analytics 67b12 and De Anima 429b10. τί ἦν is therefore really (τῷ) τί ἦν. τί, of course, is the interrogative pronoun, “what.” The phrase τί ἦν means, “what is it?” or as an indirect interrogative, which it could also be, “what it is.”

Putting it all together in a different order we have, τὸ εἶναι “being,” (τῷ) τί ἦν “for what is it?” or as an indirect interrogative, “for what it is.” Very often when there is a dative with a verb like εἰμί, it is construed as a dative of possession, which can be translated as a genitive. We could translate τὸ τί ἦν εἶναι as, “The essence/being of what it is.” The mystery of the phrase is solved. We are nevertheless saddled with an uncharacteristically unwieldy phrase to describe a common Greek philosophical term.