shake, that nature's laws are immutable. The stability of her
processes, the precision of her action, and the universality of her
laws, is the basis of all science, to which biology forms no
exception. Once establish, by clear and unmistakable demonstration,
the life history of an organism, and truly some change must have come
over nature as a whole, if that life history be not the same to-morrow
as to-day; and the same to one observer, in the same conditions, as to
another.

No amount of paradox would induce us to believe that the combining
proportions of hydrogen and oxygen had altered, in a specified
experimenter's hands, in synthetically producing water.

We believe that the melting point of platinum and the freezing point
of mercury are the same as they were a hundred years ago, and as they
will be a hundred years hence.

Now, carefully remember that so far as we can see at all, it must be
so with life. Life inheres in protoplasm; but just as you cannot get
_abstract matter_--that is, matter with no properties or modes of
motion--so you cannot get _abstract_ protoplasm. Every piece of living
protoplasm we see has a history; it is the inheritor of countless
millions of years. Its properties have been determined by its history.
It is the protoplasm of some definite form of life which has inherited
its specific history. It can be no more false to that inheritance than
an atom of oxygen can be false to its properties.

All this, of course, within the lines of the great secular processes
of the Darwinian laws; which, by the way, could not operate at all if
caprice formed any part of the activities of nature.