takes place. A commodity may be the
product of skilled labor, its value may be equivalent to a product of
unskilled labor skilled labor. The proportion in which different forms
of labor are reduced to their general standard in unskilled labor is
established by a social process going on behind the backs of the
producers, and appears to them merely customary."

Here Marx is only dealing with the value of commodities, that is of
objects produced and exchanged by private producers in a society
consisting of private producers producing for their own profit. He is
therefore not concerned here with "absolute value" whatever that may
be but only with the value which is realised in a given form of
society. This value under the given social conditions is shaped and
measured by the human labor incorporated in the commodities and this
human labor shows itself as the expression of simple human energy. But
every piece of work is not merely an expression of simple labor force.
Very many labor products require the expenditure of more or less time,
money, trouble, and acquired skill or knowledge. Do these kinds of
compound labor show at the same period of time the same commodity
values as simple labor, are they the expression of merely simple labor
force? Evidently not. The product of an hour of compound labor is a
commodity of higher, double or three times the value of a product of
an hour of simple labor. The value of the product of compound labor
can in this comparison be expressed through the measure of simple
labor; and this reduction of compound labor is carried on by means of
a social progress behind the back of the producer, by means of which
can here be established according to the theory of value but not
explained.

The thing which Marx states here is a simple fact which happens every
day before our eyes in the present capitalistic society.

(After some invective and satire hurled at Duehring Engels proceeds:)

Let us examine with regard to equality of value a little more closely.
All labor time is of equal value, that of the barrow pusher and that
of the architect. Therefore labor time and consequently labor itself
has a value. But labor is the creator of all values. It is the only
thing which gives the original products of nature a value in the
economic sense. Value in itself is nothing but the expression in a
given object of necessary, social, human labor. One might just as well
speak of and fix a value to labor as spea