YOUNG SOCRATES: Tell me of what sort.

STRANGER: Such as this: You may remember that we made an art of
calculation?

YOUNG SOCRATES: Yes.

STRANGER: Which was, unmistakeably, one of the arts of knowledge?

YOUNG SOCRATES: Certainly.

STRANGER: And to this art of calculation which discerns the differences of
numbers shall we assign any other function except to pass judgment on their
differences?

YOUNG SOCRATES: How could we?

STRANGER: You know that the master-builder does not work himself, but is
the ruler of workmen?

YOUNG SOCRATES: Yes.

STRANGER: He contributes knowledge, not manual labour?

YOUNG SOCRATES: True.

STRANGER: And may therefore be justly said to share in theoretical
science?