s forms one single consciousness, or a
collective individuality. The mind of the race is to some extent a
common function, its body a common apparatus; the one is only the
material translation of the other, and the implement performs its
function as faithfully as does the organ. One might even go farther
and maintain that the implement in the full sense of the word is an
organ; for it serves a function that is vital for the community, and
this is exposed to every change, and derives benefit from every growth
which circumstances bring to it."

The work of animals, therefore, only differs in its highest
developments from purely physiological functions, in that the animal
becomes more independent of its implements and of the product of its
labour. Notice, for instance, the progress which is shown in the
series of the mussel's shell, the spider's web, the bee's cell, the
bird's nest, and the mole's burrow. The progressive differentiation
of the products of labour keeps step with the progressive
individualisation of the labourer and with the growing material
independence of the body from its products. Mussel shell, cobweb, and
bee's cell are still produced from the secretions of the body; but
while the mussel is inseparable from its shell, the spider, at least
without immediate harm, can be detached from its web; while the bee is
still further emancipated from its structure of cells. The bird's nest
and the mole's burrow have been formed already by a manipulation of
materials foreign to the body, though in the case of the first still
by the help of secretions from the body. In both cases the animal is
almost completely independent of its product. Still the most
complicated product of animal labour is, after all, connected
inseparably with the body of the worker; and to a much less extent can
the animal be separated from its implements; therefore complete
emancipation never takes place in the animal world.

Even in the case of the anthropoid apes the transition to the
instrument and to a product of labour entirely artificial and
perfectly independent of the animal's own body, is only very slowly
completed. This is clear from a consideration of the slow process by
which man has progressed in perfecting the implements which he has
invented. From the action of the bird which beats open a nut with its
beak, or the squirrel which cracks it with its teeth, up to that of
man who, in order to open the nut, makes use of a stone lyin