Professor Moore has lately done, and the
mystery remains the same. It is a new behavior in matter, call it by
what name we will.

Inanimate nature seems governed by definite laws; that is, given the
same conditions, the same results always follow. The reactions between
two chemical elements under the same conditions are always the same. The
physical forces go their unchanging ways, and are variable only as the
conditions vary. In dealing with them we know exactly what to expect. We
know at what degree of temperature, under the same conditions, water
will boil, and at what degree of temperature it will freeze. Chance and
probability play no part in such matters. But when we reach the world of
animate nature, what a contrast we behold! Here, within certain limits,
all is in perpetual flux and change. Living bodies are never two moments
the same. Variability is the rule. We never know just how a living body
will behave, under given conditions, till we try it. A late spring frost
may kill nearly every bean stalk or potato plant or hill of corn in your
garden, or nearly every shoot upon your grapevine. The survivors have
greater powers of resistance--a larger measure of that mysterious
something we call vitality. One horse will endure hardships and
exposures that will kill scores of others. What will agitate one
community will not in the same measure agitate another. What will break
or discourage one human heart will sit much more lightly upon another.
Life introduces an element of uncertainty or indeterminateness that we
do not find in the inorganic world. Bodies still have their laws or
conditions of activity, but they are elastic and variable. Among living
things we have in a measure escaped from the iron necessity that holds
the world of dead matter in its grip. Dead matter ever tends to a static
equilibrium; living matter to a dynamic poise, or a balance between the
intake and the output of energy. Life is a peculiar activity in matter.
If the bicyclist stops, his wheel falls down; no mechanical contrivance
could be devised that could take his place on the wheel, and no
combination of purely chemical and physical forces can alone do with
matter what life does with it. The analogy here hinted at is only
tentative. I would not imply that the relation of life to matter is
merely mechanical and external, like that of the rider to his wheel. In
life, the rider and his wheel are one, but when life vanishes, the wheel
falls d