division of the sentence (λόγος) into noun and verb (ὄνομα and ῥῆμα.) Its point is to separate the enunciative sentence, or that in which there is truth or falsity, from other sentences; and then, dismissing the rest to rhetoric or poetry (where we should say grammar), to discuss the enunciative sentence (ἀποφαντικὸς λόγος), or enunciation (ἀποφανσίς), or what we should call the proposition (De Int. chap. 4). Here Aristotle, starting from the previous grammar of sentences in general, proceeded, for the first time in philosophical literature, to disengage the logic of the proposition, or that sentence which can alone be true or false, whereby it alone enters into reasoning. But in spite of this great logical achievement, he continued throughout the discourse to accept Plato’s grammatical analysis of all sentences into noun and verb, which indeed applies to the proposition as a sentence but does not give its particular elements. The first part of the work confines itself strictly to noun and verb, or the form of proposition called secundi adjacentis. Afterwards (chap. 10) proceeding to the opposition of propositions, he adds the form called tertii adjacentis, in a passage which is the first appearance, or rather adumbration, of the verb of being as a copula. In the form secundi adjacentis we only get oppositions, such as the following:—
|man is—man is not|
not-man is—not-man is not
In the form tertii adjacentis the oppositions, becoming more complex, are doubled, as follows:—
|man is just—man is not just|
man is non-just—man is not non-just
not-man is just—not-man is not just
not-man is non-just—not-man is not non-just.
The words introducing this form (δταν δὲ τὸ ἔστι τρίτον προσκατηγορῆται, chap. 10, 19 b 19), which are the origin of the phrase tertii adjacentis, disengage the verb of being (ἔστι) partially but not entirely, because they still treat it as an extra part of the predicate, and not as a distinct copula. Nor does the work get further than the analysis of some propositions into noun and verb with “is” added to the predicated verb; an analysis, however, which was a great logical discovery and led Aristotle further to the remark that “is” does not mean “exists”; e.g. “Homer is a poet” does not mean “Homer exists” (De Int. chap. 11).
How then did Aristotle get further in the logical analysis of the proposition? Not in the De Interpretatione, but in the Prior Analytics. The first adumbration was forced upon him in the former work by his theory of opposition; the complete appearance in the latter work by his theory of syllogism. In analysing the syllogism, he first says that a premiss is an affirmative or negative sentence, and then that a term is that into which a premiss is dissolved, i.e. predicate and subject, combined or divided by being and not being (Pr. An. i. 1). Here, for the first time in logical literature, subject and predicate suddenly appear as terms, or extremes, with the verb of being (τὸ εἶναι) or not being (τὸ μὴ εἶναι) completely disengaged from both, but connecting them as a copula. Why here? Because the crossing of terms in a syllogism requires it. In the syllogism “Every man is mortal and Socrates is a man,” if in the minor premiss the copula “is” were not disengaged from the predicate “man,” there would not be one middle term “man” in the two premisses. It is not necessary in every proposition, but it is necessary in the arrangement of a syllogism, to extricate the terms of its propositions from the copula; e.g. mortal—man—Socrates.
This important difference between the De Interpretatione and the Prior Analytics can only be explained by supposing that the former is the earlier treatise. It is nearer to Plato’s analysis of the sentence, and no logician would have gone back to it, after the Prior Analytics. It is not spurious, as some have supposed, nor later than the De Anima, as Zeller thought, but Aristotle in an earlier frame of mind.
Moreover we can make a history of Aristotle’s thought and gradual composition thus:
(1) Earlier acceptance in the De Interpretatione of Plato’s grammatical analysis of the sentence into noun and verb (secundi adjacentis) but gradually disengaging the proposition, and afterwards introducing the verb of being as a third thing added (tertium adjacens) to the predicated verb, for the purpose of opposition.
(2) Later logical analysis in the Prior Analytics of the proposition as premiss into subject, predicate and copula, for the purpose of syllogism; but without insisting that the original form is illogical.
3. The Eudemian Ethics and Magna Moralia in relation to the Nicomachean Ethics.—Under the name of Aristotle, three treatises on the good of man have come down to us, Ἠθικὰ Νικομάχεια (πρὸς Νικόμαχον, Porphyry), Ἠθικὰ Εὐδήμια (πρὸς Εὔδημον, Porphyry), and Ἠθικὰ μεγάλα; so like one another that there seems no tenable hypothesis except that they are the manuscript writings of one man. Nevertheless, the most usual hypothesis is that, while the Nicomachean Ethics (E.N.) was written by Aristotle to Nicomachus, the Eudemian (E.E.) was written, not to, but by, Eudemus, and the Magna Moralia (M.M.) was written by some early disciple before the introduction of Stoic and Academic elements into the Peripatetic school. The question is further complicated by the fact that three Nicomachean books (E.N. v.-vii.) and three Eudemian (E.E. Δ-Ζ) are common to the two treatises, and by the consequent question whether, on the hypothesis of different authorship, the common books, as we may style them, were written for the Nicomachean by Aristotle, or for the Eudemian Ethics by Eudemus, or some by one and some by the other author. Against the “Chorizontes,” who have advanced various hypotheses on all these points without convincing one another, it may be objected that they have not considered Aristotle’s method of gradual and simultaneous composition of manuscripts within the Peripatetic school. We have to remember the traces of his separate discourses, and his own double versions; and that, as in ancient times Simplicius, who had two versions of the Physics, Book vii., suggested that both were early versions of Book viii. on the same subject, so in modern times Torstrik, having discovered that there were two versions of the De Anima, Book ii., suggested that both were by Aristotle. Above all, we must consider our present point that Platonic influence is a sign of earliness in an Aristotelian work; and generally, the same man may both think and write differently at different times, especially if, like Aristotle, he has been a prolific author.
These considerations make it probable that the author of all three treatises was Aristotle himself; while the analysis of the treatises favours the hypothesis that he wrote the Eudemian Ethics and the Magna Moralia more or less together as the rudimentary first drafts of the mature Nicomachean Ethics.
As the Platonic philosophy was primarily moral, and its metaphysics a theory of the moral order of the universe, Aristotle from the first must have mastered the Platonic ethics. At first he adopted the somewhat ascetic views of his master about soul and body, and about goods of body and estate; but before Plato’s death he had rejected the hypothesis of forms, formal numbers and the form of the good identified with the one, by which Plato tried to explain moral phenomena; while his studies and teaching on rhetoric and poetry soon began to make him take a more tolerant view than Plato did of men’s passions. Throughout his whole subsequent life, however, he retained the fundamental doctrine, which he had learnt from Plato, and Plato from Socrates, that virtue is essential to happiness. Twice over this tenet, which makes Socrates, Plato and Aristotle one ethical school, inspired Aristotle to attempt poetry: first, in the Elegy to Eudemus of Cyprus, in which, referring to either Socrates or Plato, he praises the man who first showed clearly that a good and happy man are the same (Fragm. 673); and secondly, in the Hymn in memory of Hermias, beginning “Virtue, difficult to the human race, noblest pursuit in life” (ib. 675). Moreover, the successors of Plato in the Academy, Speusippus and Xenocrates, showed the same belief in the essentiality of virtue. The question which divided them was what the good is. Speusippus took the ascetic view that the good is a perfect condition of neutrality between two contrary evils, pain and pleasure. Xenocrates took the tolerant view that it is the possession of appropriate