58 NATURE OF CAPITAL AND INCOME [Curae IV

line to be drawn? Are we to say, for instance, that capital
is that wealth whose use extends beyond seventeen days?
And as all wealth is for future use it is also, by the same
token, all a “reserve.” To call capital a reserve does not,
therefore, in strictness, delimit it from other wealth. Even
a beggar’s crust in his pocket will tide him over a few hours.!
Equally futile is any attempt definitely to mark off
capital as that wealth which is “productive.” We have
seen that all wealth is productive in the sense that it yields
services. There was a time when the question was hotly
debated what labor was productive and what unproductive.
The distinction was barren and came to be so recognized.
No one now objects to calling all labor productive. And
if this productivity is common to all labor, it is equally
common to all wealth. If we admit that a private coachman
 is a productive worker, how can we deny that the
horse and carriage are also productive, especially as the
three merely cooperate in rendering the very same service,
— transportation ?
Finally, we cannot distinguish capital as that wealth
which bears income. All wealth bears income, for income
consists simply of the services of wealth. But the idea
that some wealth bears income and some not has been persistent
 from the time of Adam Smith, who, meaning by income
 only money income, conceived capital as the wealth
which produces income in this sense, as distinguished from
the wealth, such as dwellings, equipages, clothing, and food,
which dissipates that income. A home, according to him,
is not a source of income, but of expense, and therefore cannot
 be capital.

§ 4
In these and other ways have economists introduced, in
place of the fundamental distinctions between fund and flow,
and between wealth and services, the merely relative dis-!

 See the writer's “Precedents for Defining Capital,” Quarterly
Journal of Economics, May, 1904, p. 404.