is dumb
before such a question.

Living bodies are immersed in physical conditions as in a sea. External
agencies--light, moisture, air, gravity, mechanical and chemical
influences--cause great changes in them; but their power to adapt
themselves to these changes, and profit by them, remains unexplained.
Are morphological processes identical with chemical ones?

In the inorganic world we everywhere see mechanical adjustment, repose,
stability, equilibrium, through the action and interaction of outward
physical forces; a natural bridge is a striking example of the action of
blind mechanical forces among the rocks. In the organic world we see
living adaptation which involves a non-mechanical principle. An
adjustment is an outward fitting together of parts; an adaptation
implies something flowing, unstable, plastic, compromising; it is a
moulding process; passivity on one side, and activity on the other.
Living things struggle; they struggle up as well as down; they struggle
all round the circle, while the pull of dead matter is down only.

Behold what a good chemist a plant is! With what skill it analyzes the
carbonic acid in the air, retaining the carbon and returning the oxygen
to the atmosphere! Then the plant can do what no chemist has yet been
able to do; it can manufacture chlorophyll, a substance which is the
basis of all life on the globe. Without chlorophyll (the green substance
in plants) the solar energy could not be stored up in the vegetable
world. Chlorophyll makes the plant, and the plant makes chlorophyll. To
ask which is first is to call up the old puzzle, Which is first, the
egg, or the hen that laid it?

According to Professor Soddy, the engineer's unit of power, that of the
British cart-horse, has to be multiplied many times in a machine before
it can do the work of a horse. He says that a car which two horses used
to pull, it now takes twelve or fifteen engine-horse to pull. The
machine horse belongs to a different order. He does not respond to the
whip; he has no nervous system; he has none of the mysterious reserve
power which a machine built up of living cells seems to possess; he is
inelastic, non-creative, non-adaptive; he cannot take advantage of the
ground; his pull is a dead, unvarying pull. Living energy is elastic,
adaptive, self-directive, and suffers little loss through friction, or
through imperfect adjustment of the parts. A live body converts its fuel
into energy at a low temperatur