; but society itself is an abiding thing. So we can
study a particular bit of ore or wool or leather or a particular
hammer or spindle or sewing machine, and in those cases we shall be
studying capital goods and finding how perishable they are; but we
shall also see that a stock of them always abides as the capital of
economic society. We can cease to look at individual things and study
the permanent fund of productive wealth, which is made up of goods
like ore, wool, leather, hammers, spindles, and sewing machines. The
identity of the things which make up this stock is forever changing.
The same list of things we shall never find in the stock on any two
dates, but a supply of similar things forever abides. _Capital is this
permanent fund of productive goods, the identity of whose component
elements is forever changing. Capital goods are the shifting component
parts of this permanent aggregate._ They are the particular
instruments that, each during its own brief economic lifetime, take
their places in the endless procession of things which in its entirety
is an abiding productive agent--the co-worker of labor and its
perpetual assistant in creating consumers' wealth.

_The Business Man's View of Capital._--It is as such an abiding entity
that a business man regards capital. He describes it nearly always as
a sum of money. Thus the capital of a manufacturer is "a million
dollars" because a stock of instruments worth that amount is kept
intact in his possession. It is not allowed to waste away, however
much the constituent parts of it may shift. The waste and renewal
which business entails leave the equivalent of the million dollars
always on hand, though never in the literal shape of money. A stock of
shifting goods always worth a million dollars is, by a figure of
speech, described as a million dollars "invested in the goods."[2]

[2] We here put out of sight all questions connected with the
changing purchasing power of money. This is, in ordinary
times, the business man's habit. He considers his capital
intact if the number of dollars invested originally in his
business still appears on his inventory as representing the
net surplus of his assets over his liabilities. If a currency
were undergoing rapid inflation, a fixed amount of invested
money would represent a shrinking stock of capital goods.
This stock would last always, but would grow smaller by a
true standard of measure