rightly show what kinds will unite and what will not, proceed by the

help of science in the path of argument? And will he not ask if the

connecting links are universal, and so capable of intermixture with all

things; and again, in divisions, whether there are not other universal

classes, which make them possible?

THEAETETUS: To be sure he will require science, and, if I am not

mistaken, the very greatest of all sciences.

STRANGER: How are we to call it? By Zeus, have we not lighted

unwittingly upon our free and noble science, and in looking for the

Sophist have we not entertained the philosopher unawares?

THEAETETUS: What do you mean?

STRANGER: Should we not say that the division according to classes,

which neither makes the same other, nor makes other the same, is the

business of the dialectical science?

THEAETETUS: That is what we should say.

STRANGER: Then, surely, he who can divide rightly is able to see clearly

one form pervading a scattered multitude, and many different forms

contained under one higher form; and again, one form knit together into

a single whole and pervading many such wholes, and many forms, existing

only in separation and isolation. This is the knowledge of classes which