Volume 1 — II. THIS OPINION REFUTED BY PHILOSOPHICAL REASONS.

The futility of the above doctrine is manifest, in the first place, from the weakness of the foundation on which it rests. That foundation is no other than a kind of likeness which appears at first sight between the rudimental forms which, in the first steps of its development, are assumed by the human embryo, and the forms of some inferior animals. For the germ, by the very reason that it has not, as it was once believed, all the organism of the human body in microscopic proportions, but in order to acquire it must pass from potential to actual existence—by that very reason, is {73} subjected to continual metamorphoses, that is, to successive transformations, which give it different aspects, from that of a little disc to the perfect human figure. Now, it is clear that, in this gradual transition from the mere power to the act of perfect organization, a kind of analogy or likeness to some of the numberless forms of inferior organizations of the animal kingdom may, and must, be found in its intermediate and incomplete state.

But, evidently, between analogy and identity there is an immense difference; and the fact of there being an analogy with some of those forms, gives us no right to infer that there is one with all. Hence this theory is justly despised by the most celebrated naturalists as the whim of an extravagant fancy.

"According to Lamarck," says Frédault, in speaking of this, theory, "all the animals are but inferior grades at which the human germ stopped in its development, and man is but the result of the last efforts of a nature which has passed successively through the grades of its novitiate, and has arrived at the last term of its perfection. Presented in this view, the doctrine of epigenesis raised against itself the most simple and scientific common sense, as being manifestly erroneous. Numerous works on the development of the germ have demonstrated that appearances were taken for realities, and that imagination had created a real romance. It has been proved that if, at certain epochs of its development, the human germ has a distant resemblance either to a worm or a reptile, such resemblance is very remote, and that on this point we must believe as much as we would believe of the assertion of a man who, looking at the clouds, should say that he could discover the palaces and gardens of Armida, with horsemen and armies, and all that a heated imagination might fancy."

However, laying aside all that, the opinion which we are now examining originates, with those who uphold it, in a total absence of philosophical conceptions. That strange idea of the unity of type and of its stages, in order to establish the forms of inferior animals, would never have risen in the mind of any one who had duly considered the immutability of essences and the reason of the formation of a thing. The act of making differs from the thing made only as the means differs from the end. Both belong to the same order—one implies movement, the other rest. Their difference lies only in this: that what in the term is unfolded and complete, in its progress toward the term is found to be only sketched out, and having a tendency to formation. Hence it follows that, whatever the point of view from which we consider the embryo of each animal, it is nothing else but the total organism of the same in the course of formation; and, therefore, it differs as substantially from every other organism as the term itself toward which it proceeds. And what we affirm of the whole organism must be said of each of its parts, which are essentially related to the whole and follow the nature of the whole. The first rudiments, for instance, of the hands of man could not properly be compared to the wings of a bird. As they are hands after being made, so they are hands in the process of formation; as their structure is different, so is their being immutable.

Whatever may be the likeness between the first appearances of the human embryo and the forms of lower animals, they are not the effect of a stable existence, but of a transitory and shifting existence, which does not constitute a species, but is merely and essentially a movement toward the formation of the species. On the contrary, the forms presented by animals already constituted in their being belong to a stable and permanent existence, which diversifies one species from another. The difference, then, between the former and the latter is interior and substantial, and cannot be changed into exterior and accidental, as it would be if it consisted in {74} stopping or in travelling further on. The movement or tendency which takes place in the germ to become another thing until the said germ assumes a perfect organization relative to the being it must produce, is not a quality which can be discarded, since it is intimately combined with the subject itself in which it is found. The essence itself must be changed in it in order to obtain stability and consistency. But if the essence be changed, we are out of the question, since in that case we should have, not the human embryo arrested at this or that stage on its road, but a different being substituted for it; of analogous exterior appearance, perhaps, but substantially different, which would constitute an annual of inferior degree.

In short, each animal is circumscribed in its own species, like every other being in nature. If to reach to the perfection required by its independent existence it needs development, every step in that journey is an inchoation of the next, and cannot exist but as such. To change its nature and to make it a permanent being, is as impossible as to change one essence into another.

Again: From the opinion we are refuting it would follow that all animals, man excepted, are so many monsters, since they are nothing else but deviations, for want of ulterior development, from what nature really intends to do as a term of its action. Thus anomaly is converted into law, disorder into order, an accidental case into a constant fact.

Finally, in that hypothesis we should have to affirm not only that the inferior and more imperfect species appeared on earth before the nobler and the more akin to the unique and perfect type, but also that on the appearance of a more perfect species the preceding one had disappeared; being inferior in the scale of perfection. For what other reason could be alleged for nature's stopping at a bird when it intends to make a man, but that the causes are not properly disposed, or that circumstances are not quite favorable to the production of that perfect animal? Then when the causes are ready, and the circumstances propitious, it is necessary that man be fashioned and that the bird disappear. Now all that is contrary to experience. For all the species, together with the type, are of the same date, and we see them born constantly in the same circumstances which are common to all, either of temperature or atmosphere or latitude, etc.

The theory, then, of the unity of type in the animal kingdom and of stages of development falls to the ground, if we only look at it from a philosophical point of view.