of protesting against the disposition of his interlocutor to think that, in order to answer the question: "What is ἀρετή?" it is enough to enumerate a certain number of ἀρεταί (of the man, the woman, the child, the slave, etc.). Socrates, after congratulating himself on the fact that, instead of a single thing of which he was in search, he had a swarm before him, insists, altering his question, on determining in what they agree. Resuming the examination of one of the ἀρεταί enumerated, justice, he asks if it is ἀρετή or an ἀρετή (ἀρετή τίς) and, taking the example of form (σχῆμα) and its particular cases (τὸ στρόγγυλον, τὸ εὐθύ) asks: "What is it which is equally present in each one of these (τί ἐστι ταὐτὸν ἐπὶ πᾶσι 75 A) and of which the word 'form' is the name (ὃ δὴ ὀνομάζεις σχῆμα)?" A perfectly identical situation is, as is well known, reproduced in the Theætetus (147) when Socrates, ironically answering Theætetus, who had enumerated to him a series of particular sciences, thanks him for having supplied him with many and various things instead of that one thing for which he had asked him (ἓν αἰτηθείς) and, again repeating the question, makes it more exact by adding: "The question is not to state how many sciences there are nor to enumerate them (ἀριθμῆσαι) but to know what science is in itself". And the distinction is further elucidated by adducing the example of one who, being asked what mud (πηλός) is, instead of answering that it is "earth mixed with water," enumerates the various kinds of it: that used by potters, workmen in a furnace, etc.; and concludes by reproving Theætetus for taking such a long and interminable (ἀπέραντον) road when it was in his power to answer easily and briefly.
The following is a passage in which the term εἶδος is more distinctly applied to express the contrast between the meaning or connotation of a general name and the whole of the objects which the name denotes: οὐ τοῦτό σοι διεκελευόμην ἕν τι ἢ δύο με διδάξαι τῶν πολλῶν ὁσίων, ἀλλ’ ἐκεῖνο αὐτὸ τὸ εἶδος ᾦ πάντα τὰ ὅσια, ὅσιά ἐστιν (Euthyphr. 5 D). The correspondence between the sense in which, in passages like this, the word εἴδη is understood and that which the word property has in modern Logic, is brought out still more clearly by the frequency of the phrases which recall precisely the image of possession: εἶδος ἔχειν (cf. Hippias maj., 298 B; Symposium, 204 G; Meno, 72 G; Rep., IV., etc.).
With these phrases are classed also those in which the objects are said to share or have part in the possession (μετέχειν, μεταλαμβάνειν) of a certain εἶδος, or to enjoy it in common (κοινωνεῖν).