may be kept hard at work. Now, when trade is left free it
gives rise to division of labour, not only between town and town, county
and county, but between the most distant nations of the earth. Thus is
created what may be called #the territorial division of labour#.
Commerce between nation and nation is not only one of the best means of
increasing wealth and saving labour, but it brings us nearer to the time
when all nations will live in harmony, as if they were but one nation.

#31. The Combination of Labour.# We now see what great advantages arise
from each man learning a single trade thoroughly. This is called the
division of labour, because it divides up the work into a great many
different operations; nevertheless, it leads men to assist each other,
and to work together in manufacturing the same goods. Thus, in producing
a book, a great many trades must assist each other: type-founders cast
the type; mechanics make the printing press; the paper is manufactured
at the paper works; printers' ink is prepared at other works; the
publishers arrange the business; the author supplies the copy; the
compositors set up the type; the reader corrects the proofs; the
pressmen work off the printed sheets; then there are still the
bookbinders, and the booksellers, besides a great many other small
trades which supply the tools wanted by the principal trades. Thus,
society is like a very complicated machine, in which there is a great
number of wheels, and wheels within wheels; each part goes on attending
to its own business, and doing the same work over and over again. There
is what we should call a #complex organization# (Greek, organon,
instrument), that is to say, different people and different
trades work as instruments of each other, all assisting in the ultimate
result.

But it is to be observed that nobody plans out these systems of divided
labour; indeed few people ever know how many trades there are, and how
they are connected together. There are said to be about thirty-six
distinct kinds of employment in making and putting together the parts of
a piano; there are about forty trades engaged in watchmaking; in the
cotton business there are more than a hundred occupations. But new
trades are frequently created, especially when any new discovery takes
place; thus, there are at least sixteen different trades occupied in
photography, or in making the things required by photographers; and
railways have produced whole series of