his meditations during the closing years of the
eighteenth century, must gradually have led to a change of views.

It was said by Isidore Geoffroy St. Hilaire that Lamarck was "long a
partisan of the immutability of species,"[160] but the use of the word
"partisan" appears to be quite incorrect, as he only in one instance
expresses such views.

The only place where we have seen any statement of Lamarck's earlier
opinions is in his _Recherches sur les Causes des principaux Faits
physiques_, which was written, as the "advertisement" states, "about
eighteen years" before its publication in 1794. The treatise was
actually presented April 22, 1780, to the Academie des Sciences.[161] It
will be seen by the following passages, which we translate, that, as
Huxley states, this view presents a striking contrast to those to be
found in the _Philosophie zoologique_:

"685. Although my sole object in this article [article premier,
p. 188] has only been to treat of the physical cause of the
maintenance of life of organic beings, still I have ventured to urge
at the outset that the existence of these astonishing beings by no
means depends on nature; that all which is meant by the word nature
cannot give life--namely, that all the faculties of matter, added to
all possible circumstances, and even to the activity pervading the
universe, cannot produce a being endowed with the power of organic
movement, capable of reproducing its like, and subject to death.

"686. All the individuals of this nature which exist are derived
from similar individuals, which, all taken together, constitute the
entire species. However, I believe that it is as impossible for man
to know the physical origin of the first individual of each species
as to assign also physically the cause of the existence of matter or
of the whole universe. This is at least what the result of my
knowledge and reflection leads me to think. If there exist any
varieties produced by the action of circumstances, these varieties
do not change the nature of the species (_ces varietes ne denaturent
point les especes_); but doubtless we are often deceived in
indicating as a species what is only a variety; and I perceive that
this error may be of consequence in reasoning on this subject"
(tome ii., pp. 213-214).

It must apparently remain a matter of uncertainty whether this opinion,
so decisively stated, was that of Lamarck at thirty-two years