OF LABOUR.

49

the labourer receives. This quantity of silver
expresses the value of his labour, in the same
way that a certain quantity of silver expresses
the value of a yard of cloth. Now the quan-
tity of ‘silver by which the value of a yard of
cloth is expressed, we term the price of the
cloth, and, in a manner strictly analogous, the
quantity of silver by which the value of a day’s
labour is expressed, we term the wages of la-
bour. The price of cloth and the wages of labour
are so far exactly correspondent expressions.
But when I speak of the price of cloth as the
subject of causation or change, I do not intend
the silver itself. The price of the cloth may
be twenty shillings, but what causes the price
is not what causes that quantity of silver. To
consider the price as being or consisting in the
actual silver itself, is an error of the same kind
as to consider the length of a piece of timber
as consisting in the instrument which we em-
ploy to measureit. Were to speak of the real
value of the price of cloth, or of the labour and
capital employed in producing the price of