f a cell is a complex chemical compound we call protoplasm,
whose elements are identical with chemical substances outside the living
world. Is there any ground for supposing that the properties of protoplasm
are due to any other causes than those which may be found in the chemical
and physical constitution of protoplasm? In brief, is life physics and
chemistry? Nowadays the majority of biologists believe that it is. Just as
the properties of water are contributed by the elements hydrogen and
oxygen which unite to form it, just so the marvelous properties of
protoplasm are regarded as the inevitable derivatives of the combined
properties of the various chemical elements which constitute protoplasm.
Biologists have known for more than a century, since the work of Lavoisier
and Laplace in 1780, that the fundamental process of the living mechanism
is oxidation, and that this process is the same, as they said, for the
burning candle and the guinea pig. Beginning with Woehler, in 1828, scores
of students of physiological chemistry have duplicated the chemical
processes of living matter, which were regarded as so peculiar to the
living organism that they seemed to be due to the operation of a
non-mechanical and vital cause. The investigator mentioned was the first to
construct artificially from inorganic substances the nitrogen-containing
ash product of the living organism called urea. Now hundreds of so-called
organic compounds have been made synthetically and their number is added
to week after week. Therefore, the biologist who finds that a physical and
chemical analysis of some vital processes is possible, and that the
analysis is being extended with astonishing rapidity, finds himself unable
to regard protoplasmic activity as anything different in kind or category
from the processes of physics and chemistry which go on in the world of
dead things.

It is true that even at the present time some biologists are reluctant to
accept the thoroughgoing mechanical interpretation of organic phenomena,
partly because these are so complex that their ultimate constituents
cannot be discerned, but more often on account of the apparently
purposeful nature of biological processes. Some, indeed, have gone so far
as to postulate something like consciousness which controls and directs
the formation of protoplasm, and the exercise of its distinctive
properties in the way of growth, reproduction, and embryonic development
into the adapted adu