est cette _forme substantielle_ dont on jonait autrefois avec tant
de facilite. Aristote disait que 'Si l'art de batir etait dans le
bois, cet art agirait comme la nature.' A la place de _l'art de
batir_ M. Darwin met _l'election naturelle_, et c'est tout un: l'un
n'est pas plus chimerique que l'autre." (P. 31.)

And this is really all that M. Flourens can make of Natural Selection.
We have given the original, in fear lest a translation should be
regarded as a travesty; but with the original before the reader, we may
try to analyse the passage. "For an organized being, Nature is only
organization, neither more nor less."

Organized beings then have absolutely no relation to inorganic nature: a
plant does not depend on soil or sunshine, climate, depth in the ocean,
height above it; the quantity of saline matters in water have no
influence upon animal life; the substitution of carbonic acid for oxygen
in our atmosphere would hurt nobody! That these are absurdities no one
should know better than M. Flourens; but they are logical deductions
from the assertion just quoted, and from the further statement that
natural selection means only that "organization chooses and selects
organization."

For if it be once admitted (what no sane man denies) that the chances of
life of any given organism are increased by certain conditions (A) and
diminished by their opposites (B), then it is mathematically certain
that any change of conditions in the direction of (A) will exercise a
selective influence in favour of that organism, tending to its increase
and multiplication, while any change in the direction of (B) will
exercise a selective influence against that organism, tending to its
decrease and extinction.

Or, on the other hand, conditions remaining the same, let a given
organism vary (and no one doubts that they do vary) in two directions:
into one form (a) better fitted to cope with these conditions than the
original stock, and a second (b) less well adapted to them. Then it is
no less certain that the conditions in question must exercise a
selective influence in favour of (a) and against (b), so that (a)
will tend to predominance, and (b) to extirpation.

That M. Flourens should be unable to perceive the logical necessity of
these simple arguments, which lie at the foundation of all Mr. Darwin's
reasoning; that he should confound an irrefragable deduction from the
observed relations of organisms to the cond