The atmosphere of philosophic France, as well as of England and Germany in the eighteenth century, was charged with inquiries into the origin of things material, though more especially of things immaterial. It was a period of energetic thinking. Whether Lamarck had read the works of these philosophers or not we have no means of knowing. Buffon, we know, was influenced by Leibnitz.
Did Buffon’s guarded suggestions have no influence on the young Lamarck? He enjoyed his friendship and patronage in early life, frequenting his house, and was for a time the travelling companion of Buffon’s son. It should seem most natural that he would have been personally influenced by his great predecessor, but we see no indubitable trace of such influence in his writings. Lamarckism is not Buffonism. It comprises in the main quite a different, more varied and comprehensive set of factors.[158]
Was Lamarck influenced by the biological writings of Haller, Bonnet, or by the philosophic views of Condillac, whose Essai sur l’Origine des Connaissances humaines appeared in 1786; or of Condorcet, whom he must personally have known, and whose Esquisse d’un Tableau historique des Progrès de l’Esprit humain was published in 1794?[159] In one case only in Lamarck’s works do we find reference to these thinkers.
Was Lamarck, as the result of his botanical studies from 1768 to 1793, and being puzzled, as systematic botanists are, by the variations of the more plastic species of plants, led to deny the fixity of species?
We have been unable to find any indications of a change of views in his botanical writings, though his papers are prefaced by philosophical reflections.
It would indeed be interesting to know what led Lamarck to change his views. Without any explanation as to the reason from his own pen, we are led to suppose that his studies on the invertebrates, his perception of the gradations in the animal scale from monad to man, together with his inherent propensity to inquire into the origin of things, also his studies on fossils, as well as the broadening nature of his zoölogical investigations and 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 Académie 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 variétés ne dénaturent point les espèces); 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 of age, and which he allowed to remain, as then stated, for eighteen years, or whether he inserted it when reading the proofs in 1794. It would seem as if it were the expression of his views when a botanist and a young man.