only--affords a real explanation, up to a certain point, of how ordinary
labour as a whole, without ceasing to be ordinary labour, may rise from
a lower to a higher grade of efficiency.

But such simple divisions of labour as those which are here in question
fail, for a reason which will be specified in another moment, to carry
us far in the history of industrial progress. They do but bring us to
the starting-point of production as it exists to-day. The efficiency of
productive effort has made all its most astounding advances since the
precise time at which the _Wealth of Nations_ was written; and these
advances we shall find that it is quite impossible to explain merely by
a further division of average and equal labour. Such a further division
has no doubt been an element of the process; but it is an explanation
which itself requires explaining. Even in Adam Smith's time two other
factors were at work, which have ever since been growing in magnitude
and importance; and the secret of modern production lies, we shall find,
in these. I call them two, but fundamentally there is only one, for
that which is most obvious, and of which I shall speak first, is
explainable only as the direct result of the second. This, the most
obvious factor, is the modern development of machinery. The other is the
growing application of exceptional mental powers, not to the _manual
labour of the men by whom these powers are possessed_, but to the
_process of directing and co-ordinating the divided labours of others_.

Now, as to machinery, Marx and his followers, as we have seen, maintain
that it represents nothing but the average labour of the past; and so
long as it exists only in its smaller and simpler forms, the devising
and constructing of which are not referable to any faculties which we
are able to distinguish from those of the average labourer, we have
further seen that the theory of Marx holds good. Labour produces alike