"Positive facts are the only solid ground for man; the deductions he draws from them are a very different matter. Outside the facts of nature all is a question of probabilities, and the most that can be said is that some conclusions are more probable than others."
Lamarck's poverty was perhaps one main reason of the ease with which it was found possible to neglect his philosophical opinions. Science is not a kingdom into which a poor man can enter easily, if he happens to differ from a philosopher who gives good dinners, and has "his sisters and his cousins and his aunts" to play the part of chorus to him. Lamarck's two daughters do not appear to have been the kind of persons who could make effective sisters or cousins or aunts. Men of science are of like passions even with the other holy ones who have set themselves up in all ages as the pastors and prophets of mankind. The saint has commonly deemed it to be for the interests of saintliness that he should strain a point or two in his own favour—and the more so according as his reputation for an appearance of candour has been the better earned. If, then, Lamarck's opponents could keep choruses, while Lamarck had nothing to fall back upon but the merits of his case only, it is not surprising that he should have found himself neglected by the scientists of his own time. Moreover he was too old to have undertaken such an unequal contest. If he had been twenty years younger when he began it, he would probably have enjoyed his full measure of success before he died.
Not that Lamarck can claim, as a thinker, to stand on the same level with Dr. Darwin, and still less so with Buffon. He attempted to go too fast and too far. Seeing that if we accept descent with modification, the question arises whether what we call life and consciousness may not themselves be evolved from some thing or things which looked at one time so little living and conscious that we call them inanimate—and being anxious to see his theory reach, and to follow it, as far back as possible, he speculates about the origin of life; having formed a theory thereon, he is more inclined to interpret the phenomena of lower animal life so as to make them fit in with his theory, than as he would have interpreted them if there had been no theory at stake.
Thus his denial that sensation, and much more, intelligence and deliberate action, can exist without a brain and a nervous system, has led him to deny sensation, consciousness, and intelligence to many animals which act in such manner as would certainly have made him say that they feel and know what they are about, if he had formed no theory about brains and nervous systems.
Nothing can be more different than the manners in which Lamarck and Dr. Darwin wrote on this head. Lamarck over and over again maintains that where there is no nervous system there can be no sensation. Combating, for example, the assertion of Cabanis, that to live is to feel, he says that "the greater number of the polypi and all the infusoria, having no nervous system, it must be said of them as also of worms, that to live is still not to feel; and so again of plants."[199]
How different from this is the un-theory-ridden language of Dr. Darwin, quoted on p. 116 of this work.
Lamarck again writes:—
"The very imperfect animals of the lowest classes, having no nervous system, are simply irritable, have nothing but certain habits, experience no sensations, and never conceive ideas."
This, in the face of the performances of the amœba—a minute jelly speck, without any special organ whatever—in making its tests, cannot be admitted. Is it possible that Lamarck was in some measure misled by believing Buffon to be in earnest when he advanced propositions little less monstrous?
"But," continues Lamarck, "the less imperfect animals which have a nervous system, though they have not the organ of intelligence, have instinct, habits, and proclivities; they feel sensations, and yet form no ideas whatever. I venture to say that where there is no organ for a faculty that faculty cannot exist."[200]