Cuvier expressed some dissatisfaction with this report on its being read;[110] and a short time afterwards,[111] represented Geoffroy Saint-Hilaire as having asserted that the new views of Laurencet and Meyranx refuted completely the notion of the great interval which exists between molluscous and vertebrate animals. Geoffroy protested against such an interpretation of his expressions; but it soon appeared, by the controversial character which the discussions on this and several other subjects assumed, that a real opposition of opinions was in action.
[110] Princ. de Phil. Zool. discutés en 1830, p. 36.
[111] p. 50.
Without attempting to explain the exact views of Geoffroy, (we may, perhaps, venture to say that they are hardly yet generally understood with sufficient distinctness to justify the mere historian of science in attempting such an explanation,) their general tendency may be sufficiently collected from what has been said; and from the phrases in which his views are conveyed.[112] The principle of connexions, the elective affinities of organic elements, the equilibrization of organs;—such are the designations of the leading doctrines which are unfolded in the preliminary discourse of his Anatomical Philosophy. Elective affinities of organic elements are the forces by which the vital structures and varied forms of living things are produced; and the principles of connexion and equilibrium of these forces in the various parts of the organization prescribe limits and conditions to the variety and developement of such forms.
[112] Phil. Zool. 15.
The character and tendency of this philosophy will be, I think, [486] much more clear, if we consider what it excludes and denies. It rejects altogether all conception of a plan and purpose in the organs of animals, as a principle which has determined their forms, or can be of use in directing our reasonings. “I take care,” says Geoffroy, “not to ascribe to God any intention.”[113] And when Cuvier speaks of the combination of organs in such order that they may be in consistence with the part which the animal has to play in nature; his rival rejoins,[114] I “know nothing of animals which have to play a part in nature.” Such a notion is, he holds, unphilosophical and dangerous. It is an abuse of final causes which makes the cause to be engendered by the effect. And to illustrate still further his own view, he says, “I have read concerning fishes, that because they live in a medium which resists more than air, their motive forces are calculated so as to give them the power of progression under those circumstances. By this mode of reasoning, you would say of a man who makes use of crutches, that he was originally destined to the misfortune of having a leg paralysed or amputated.”
[113] “Je me garde de prêter à Dieu aucune intention.” Phil. Zool. 10.
[114] “Je ne connais point d’animal qui doive jouer un rôle dans la nature.” p. 65.
How far this doctrine of unity in the plan in animals, is admissible or probable in physiology when kept within proper limits, that is, when not put in opposition to the doctrine of a purpose involved in the plan of animals, I do not pretend even to conjecture. The question is one which appears to be at present deeply occupying the minds of the most learned and profound physiologists; and such persons alone, adding to their knowledge and zeal, judicial sagacity and impartiality, can tell us what is the general tendency of the best researches on this subject.[115] But when the anatomist expresses such opinions, and defends them by such illustrations as those which I have just quoted,[116] we perceive that he quits the entrenchments of his superior science, in which he might [487] have remained unassailable so long as the question was a professional one; and the discussion is open to those who possess no peculiar knowledge of anatomy. We shall, therefore, venture to say a few words upon it.
[115] So far as this doctrine is generally accepted among the best physiologists, we cannot doubt the propriety of Meckel’s remark, (Comparative Anatomy, 1821, Pref. p. xi.) that it cannot be truly asserted either to be new, or to be peculiarly due to Geoffroy Saint-Hilaire.