(4) But this science, this Dialectic essential to all the three classes alike, what, in sum, is it?

It is the Method, or Discipline, that brings with it the power of pronouncing with final truth upon the nature and relation of things- what each is, how it differs from others, what common quality all have, to what Kind each belongs and in what rank each stands in its Kind and whether its Being is Real-Being, and how many Beings there are, and how many non-Beings to be distinguished from Beings.

Dialectic treats also of the Good and the not-Good, and of the particulars that fall under each, and of what is the Eternal and what the not Eternal- and of these, it must be understood, not by seeming-knowledge but with authentic science.

All this accomplished, it gives up its touring of the realm of sense and settles down in the Intellectual Kosmos and there plies its own peculiar Act: it has abandoned all the realm of deceit and falsity, and pastures the Soul in the "Meadows of Truth": it employs the Platonic division to the discernment of the Ideal-Forms, of the Authentic-Existence and of the First-Kinds : it establishes, in the light of Intellection, the unity there is in all that issues from these Firsts, until it has traversed the entire Intellectual Realm: then, resolving the unity into the particulars once more, it returns to the point from which it starts.

Now rests: instructed and satisfied as to the Being in that sphere, it is no longer busy about many things: it has arrived at Unity and it contemplates: it leaves to another science all that coil of premisses and conclusions called the art of reasoning, much as it leaves the art of writing: some of the matter of logic, no doubt, it considers necessary- to clear the ground- but it makes itself the judge, here as in everything else; where it sees use, it uses; anything it finds superfluous, it leaves to whatever department of learning or practice may turn that matter to account.

(19) Having established our four primary genera, it remains for us to enquire whether each of them of itself alone produces species. And especially, can Being be divided independently, that is without drawing upon the other genera? Surely not: the differentiae must come from outside the genus differentiated: they must be differentiae of Being proper, but cannot be identical with it.

Where then is it to find them? Obviously not in non-beings. If then in beings, and the three genera are all that is left, clearly it must find them in these, by conjunction and couplement with these, which will come into existence simultaneously with itself.

But if all come into existence simultaneously, what else is produced but that amalgam of all Existents which we have just considered ? How can other things exist over and above this all-including amalgam? And if all the constituents of this amalgam are genera, how do they produce species? How does Motion produce species of Motion? Similarly with Stability and the other genera.

A word of warning must here be given against sinking the various genera in their species; and also against reducing the genus to a mere predicate, something merely seen in the species. The genus must exist at once in itself and in its species; it blends, but it must also be pure; in contributing along with other genera to form Substance, it must not destroy itself. There are problems here that demand investigation.

But since we identified the amalgam of the Existents with the particular intellect, Intellect as such being found identical with Being or Substance, and therefore prior to all the Existents, which may be regarded as its species or members, we may infer that the intellect, considered as completely unfolded, is a subsequent.

Our treatment of this problem may serve to promote our investigation; we will take it as a kind of example, and with it embark upon our enquiry.