manity possible.

As to the second requirement for production, namely:

(2) Tools and machines, it is obvious that "tools and machines" are made
of raw material by human work, mental and muscular.

And, finally:

(3) The application of power. Different sources of natural energy and
power are known. The most important available source of energy for this
globe is the sun--the heat of the sun. This solar heat is the origin of
water power, of wind power, and of the power bound up in coal, of the
chemistry, growth and transforming agency of plants.(10)

All foods which the animals as well as the humans use are, already, the
result of the solar energy transformed into what may be called chemical
energy. Transformation of energies is building up of life.

It is to be clearly seen that the only source of energy which can be
directly appropriated and used by man or animal is vegetable food found in
the wilderness; no other sources of power are available for _direct_ use;
they have first to be mastered and directed by human brain. The same is
true in regard to the getting of animal food, the creation of a water- or
windmill, or a steam engine, or the art of using a team of horses, or a
bushel of wheat; these are not available except by the use of the human
"time-binding" power.

This short survey of facts, known to everybody, brings us to the
conclusion that all problems of production come ultimately to the analysis
of

(1) Natural resources of raw material and natural energy, freely supplied
by nature, which, as we have seen, in the form as produced by nature
alone, have very little or no value for humanity;

(2) The activity of the human brain (because human muscles are always
directed by the brain) which gives value to the otherwise useless raw
materials and energies.

Hence, to understand the processes of production, it is essential to
realize that humanity is able to survive only by virtue of the capacity of
humans to exploit natural resources--to convert the products of nature into
forms available for human needs. If humanity had only the capacity of
apes, depending exclusively on wild fruits and the like, they would be
confined to those comparatively small regions of the globe where the
climate and the fertility of the soil are specially favorable. But in the
case supposed, humans would not be humans, they would not be
time-binders--they would be animals--mere space-binders.

There are other facts which must b