same kind of pleasure which you might have derived from some rhapsode's
recitation of Homer; for you do not believe a word of what has been said.
But come now, give me an answer to this question. Are not certain things
useful to the builder when he is building a house?

CRITIAS: They are.

SOCRATES: And would you say that those things are useful which are
employed in house building,--stones and bricks and beams and the like, and
also the instruments with which the builder built the house, the beams and
stones which they provided, and again the instruments by which these were
obtained?

CRITIAS: It seems to me that they are all useful for building.

SOCRATES: And is it not true of every art, that not only the materials but
the instruments by which we procure them and without which the work could
not go on, are useful for that art?

CRITIAS: Certainly.

SOCRATES: And further, the instruments by which the instruments are
procured, and so on, going back from stage to stage ad infinitum,--are not
all these, in your opinion, necessary in order to carry out the work?

CRITIAS: We may fairly suppose such to be the case.

SOCRATES: And if a man has food and drink and clothes and the other things
which are useful to the body, would he need gold or silver or any other
means by which he could procure that which he now has?