Relevant Texts in Other Dialogues

To students of the middle dialogues, the Stranger's talk of dividing things according to Forms may sound reassuringly familiar. Before returning for a closer look at the Stranger's remarks in this regard, let us recall some similar remarks by Socrates of the middle period.

At Republic 454A, Socrates tells Glaucon that people often are unable to distinguish between disputation and genuine discussion because they lack the ability to divide things according to Forms (μὴ δύνασθαι κατ᾿ εἴδη διαιρούμενοι: 454A6). This failure is comparable to that of the “clever people” of Statesman 284E11, whose inability to distinguish the two kinds of measurement is attributed to exactly the same cause (μὴ κατ᾿ εἴδη … διαιρουμένους: 285A4–5).

At Cratylus 424C, in their discussion of letters and syllables, Socrates tells Hermogenes that vowels should be divided from other elements according to Forms (or classes) (διελέσθαι … κατὰ εἴδη: 424C6). This brings to mind the story of Theuth in the Philebus. As we recall (from section 8.4), Theuth was credited with having first discerned vowels, semivowels, and mutes within the Unlimited range of vocal sound. In describing this achievement, Socrates refers to mutes as a third class (τρίτον … εἶδος: 18C2) to be set aside as distinct. The distinctions among phonemic sounds that Hermogenes is advised to observe correspond to those established by Theuth in the story of the Philebus.

The Phaedrus contains three explicit references to the procedure of dividing according to Forms.