is he a captain of sailors or a mere sailor?

A captain of sailors.

The circumstance that he sails in the ship is not to be taken into account; neither is he to be called a sailor; the name pilot by which he is distinguished has nothing to do with sailing, but is significant of his skill and of his authority over the sailors.

Very true, he said.

Now, I said, every art has an interest?

Certainly.

For which the art has to consider and provide?

Yes, that is the aim of art.

And the interest of any art is the perfection of it — this and nothing else?