arts which do not manufacture the actual thing, but which
furnish the necessary tools for the manufacture, without which the
several arts could not fulfil their appointed work, are co-operative;
but those which make the things themselves are causal.

YOUNG SOCRATES: A very reasonable distinction.

STRANGER: Thus the arts which make spindles, combs, and other
instruments of the production of clothes, may be called co-operative,
and those which treat and fabricate the things themselves, causal.

YOUNG SOCRATES: Very true.

STRANGER: The arts of washing and mending, and the other preparatory
arts which belong to the causal class, and form a division of the
great art of adornment, may be all comprehended under what we call the
fuller's art.

YOUNG SOCRATES: Very good.

STRANGER: Carding and spinning threads and all the parts of the process
which are concerned with the actual manufacture of a woollen garment
form a single art, which is one of those universally acknowledged,--the
art of working in wool.

YOUNG SOCRATES: To be sure.

STRANGER: Of working in wool, again, there are two divisions, and both
these are parts of two arts at once.

YOUNG SOCRATES: How is that?

STRANGER: Carding and one half of the use of the comb, and the other
processes of wool-working which separate the composite, may be classed
together as belonging both to the art of wool-working, and also to one
of the two great arts which are of universal application--the art of
composition and the art of division.

YOUNG SOCRATES: Yes.

STRANGER: To the latter belong carding and the other processes of which
I was just now speaking; the art of discernment or division in wool and
yarn, which is effected in one manner with the comb and in another with
the hands, is variously described under all the names which I just now
mentioned.

YOUNG SOCRATES: Very true.

STRANGER: Again, let us take some process of wool-working which is also
a portion of the art of composition, and, dismissing the elements of
division which we found there, make two halves, one on the principle of
composition, and the other on the principle of division.

YOUNG SOCRATES: Let that be done.

STRANGER: And once more, Socrates, we must divide the part which belongs
at once both to wool-working and composition, if we are ever to discover
satisfactorily the aforesaid art of weaving.

YOUNG SOCRATES: We must.

STRANGER: Yes, certainly, and let us call one part of the art the