SOCRATES: The agent or cause always naturally leads, and the patient or effect naturally follows it?

PROTARCHUS: Certainly.

SOCRATES: Then the cause and what is subordinate to it in generation are not the same, but different?

PROTARCHUS: True.

SOCRATES: Did not the things which were generated, and the things out of which they were generated, furnish all the three classes?

PROTARCHUS: Yes.

SOCRATES: And the creator or cause of them has been satisfactorily proven to be distinct from them,—and may therefore be called a fourth principle?

PROTARCHUS: So let us call it.

SOCRATES: Quite right; but now, having distinguished the four, I think that we had better refresh our memories by recapitulating each of them in order.

PROTARCHUS: By all means.