Ion. No, that will be the reason.

  Soc. And every art is appointed by God to have knowledge of a
certain work; for that which we know by the art of the pilot we do not
know by the art of medicine?

  Ion. Certainly not.

  Soc. Nor do we know by the art of the carpenter that which we know
by the art of medicine?

  Ion. Certainly not.

  Soc. And this is true of all the arts;- that which we know with
one art we do not know with the other? But let me ask a prior
question: You admit that there are differences of arts?

  Ion. Yes.

  Soc. You would argue, as I should, that when one art is of one
kind of knowledge and another of another, they are different?

  Ion. Yes.

  Soc. Yes, surely; for if the subject of knowledge were the same,
there would be no meaning in saying that the arts were different,-
if they both gave the same knowledge. For example, I know that here
are five fingers, and you know the same. And if I were to ask
whether I and you became acquainted with this fact by the help of
the same art of arithmetic, you would acknowledge that we did?

  Ion. Yes.

  Soc. Tell me, then, what I was intending to ask you- whether this
holds universally? Must the same art have the same subject of
knowledge, and different arts other subjects of knowledge?

  Ion. That is my opinion, Socrates.

  Soc. Then he who has no knowledge of a particular art will have no
right judgment of the sayings and doings of that art?

  Ion. Very true.

  Soc. Then which will be a better judge of the lines which you were
reciting from Homer, you or the charioteer?

  Ion. The charioteer.

  Soc. Why, yes, because you are a rhapsode and not a charioteer.

  Ion. Yes.

  Soc. And the art of the rhapsode is different from that of the
charioteer?

  Ion. Yes.

  Soc. And if a different knowledge, then a knowledge of different
matters?

  Ion. True.

  Soc. You know the passage in which Hecamede, the concubine of
Nestor, is described as giving to the wounded Machaon a posset, as
he says,

  Made with Pramnian wine; and she grated cheese of goat's milk with a
grater of bronze, and at his side placed an onion which gives a relish
to drink.

Now would you say that the art of the rhapsode or the art of
medicine was better able to judge of the propriety of these lines?

  Ion. The art of medicine.

  Soc. And when Homer says,

  And she descended into the deep like a leaden plummet, which, set in
the horn of ox that ranges in the fields, rushes along carrying
death among the ravenous fishes,-

will the art of the fisherman or of the rhapsode be better able to
judge whether these lines are rightly expressed or not?

  Ion. Clearly, Socrates, the art of the fisherman.

  Soc. Come now, suppose that you were to say to me: "Since you,
Socrates, are able to assign different passages in Homer to their
corresponding arts, I wish that you would tell me what are the
passages of which the excellence ought to be judged by the prophet and
prophetic art"; and you will see how readily and truly I shall
answer you. For there are many such passages, particularly in the
Odyssey; as, for example, the passage in which Theoclymenus the
prophet of the house of Melampus says to the suitors:-

  Wretched men! what is happening to you? Your heads and your faces
and your limbs underneath are shrouded in night; and the voice of
lamentation bursts forth, and your cheeks are wet with tears. And