s
also gratified. This first specialisation of function, once commenced,
tends ever to become more decided. On the side of the weapon-maker
continued practice gives increased skill--increased superiority to his
products: on the side of his clients, cessation of practice entails
decreased skill. Thus the influences that determine this division of
labour grow stronger in both ways; and the incipient heterogeneity is,
on the average of cases, likely to become permanent for that generation,
if no longer.

Observe now, however, that this process not only differentiates the
social mass into two parts, the one monopolising, or almost
monopolising, the performance of a certain function, and the other
having lost the habit, and in some measure the power, of performing that
function; but it tends to imitate other differentiations. The advance we
have described implies the introduction of barter,--the maker of weapons
has, on each occasion, to be paid in such other articles as he agrees to
take in exchange. But he will not habitually take in exchange one kind
of article, but many kinds. He does not want mats only, or skins, or
fishing gear, but he wants all these; and on each occasion will bargain
for the particular things he most needs. What follows? If among the
members of the tribe there exist any slight differences of skill in the
manufacture of these various things, as there are almost sure to do, the
weapon-maker will take from each one the thing which that one excels in
making: he will exchange for mats with him whose mats are superior, and
will bargain for the fishing gear of whoever has the best. But he who
has bartered away his mats or his fishing gear, must make other mats or
fishing gear for himself; and in so doing must, in some degree, further
develop his aptitude. Thus it results that the small specialities of
faculty possessed by various members of the tribe, will tend to grow
more decided. If such transactions are from time to time repeated, these
specialisations may become appreciable. And whether or not there ensue
distinct differentiations of other individuals into makers of particular
articles, it is clear that incipient differentiations take place
throughout the tribe: the one original cause produces not only the first
dual effect, but a number of secondary dual effects, like in kind, but
minor in degree. This process, of which traces may be seen among groups
of schoolboys, cannot well produce any lasting eff