The following are always productive:

Labour and expenditure, of which the direct object or effect is the
creation of some material product useful or agreeable to mankind.

Labour and expenditure, of which the direct effect and object are, to
endow human or other animated beings with faculties or qualities useful
or agreeable to mankind, and possessing exchangeable value.

Labour and expenditure, which without having for their direct object the
creation of any useful material product or bodily or mental faculty or
quality, yet tend indirectly to promote one or other of those ends, and
are exerted or incurred solely for that purpose.

The following are partly productive and partly unproductive, and cannot
with propriety be ranged decidedly with either class:

Labour or expenditure which does indeed create, or promote the creation
of, some useful material product or bodily or mental faculty or quality,
but which is not incurred or exerted for that sole end; having also for
another, and perhaps its principal end, enjoyment, or the promotion of
enjoyment.

Such are the labour of the judge, the legislator, the police-officer,
the soldier; and the expenditure incurred for their support. These
functionaries protect and secure mankind in the exclusive possession of
such material products or acquired faculties as belong to them; and by
the security which they so confer, they indirectly increase production
in a degree far more than equivalent to the expense which is necessary
for their maintenance. But this is not the only purpose for which they