The advocates of the law of evolution had assuredly done much in preparing the way for Darwin, as they had insisted that certain advances in detail were undeniable and built up theories from the chaotic material provided by special research—especially seeing that some of the ablest naturalists of the time were amongst them, who determined to retain speculation in zoology and botany. But, on the other hand, it cannot be questioned that the confused nature of their fundamental idea, which, in fact, was not far removed from the theological notion of the vital force, gave the rigid and “exact” academic workers an apparent right to reject all speculation on the possibility of an evolution of species as an unscientific dream. The aged Bronn was in 1860 one of the most prudent and sober of the advocates of the inner principle of evolution. He candidly acknowledged that Darwin had struck a severe blow at the great idea of his life, on one side at least. Darwin’s work not merely dismissed God to the wings as a personality, but even left no room for the finger of God, for his spiritual writing on the walls of the living world. It found evidence of natural laws alone. From them came, if not life itself, at all events selection, adaptation, and evolution by virtue of this increasing adaptation—the higher advance that converted the fish into a lizard and the lizard into a mammal. The fine old worker, with an age of indefatigable labour behind him, though he had not got beyond the idea of a “law of evolution,” looked on Darwin with a mixture of fear and admiration as he cut into the very heart of these problems. He added amiable notes to the work to the effect that one would like to go so far, but the distance was intimidating. In fact, he omitted altogether from his translation the very important phrase that “light would be thrown on the origin of man.” It would be a terrible affair, he thought, if the discussion were at once turned on this. Man himself owing his origin neither to God nor the finger of God, but to natural selection in the ordinary course of natural laws! It was not to be thought of. Hence the phrase was struck out, as quite too extravagant, in his otherwise admirable work.
Bronn had himself become something of a revolutionary amongst his colleagues by the translation. The rigidly “exact” workers crossed themselves before the Germanised work. Most of the “evolutionists” in the older sense had by no means the bonhomie to speak even of a “possibility” like the patriarch Bronn. From the first Darwin was—Haeckel was the first to experience it—branded with the anathemas of the two opposite schools of science in Germany. On the one hand the rigorous and exact workers declared that his teaching was pure metaphysics, because it sought to prove evolution and contemplated vast ideal connections. On the other hand the Dualist metaphysicians denounced him as an empiric of the worst character, who sought to replace the great ideal elements in the world by a few miserable natural necessities. It is significant to find that Schopenhauer, the brilliant thinker, regarded the Origin of Species as one of the empirical soapsud or barber books produced by exact investigation, which he thoroughly despised from his metaphysical point of view. And there were already (there are more to-day) whole schools of zoology and botany that looked upon Darwin’s theoretical explanations as unscientific “mysticism,” “metaphysics,” and “philosophy in the worst sense of the word.”
Haeckel read the dangerous book at Berlin in May, 1860. “It profoundly moved me,” he writes to me, “at the first reading. But as all the Berlin magnates (with the single exception of Alexander Braun) were against it, I could make no headway in my defence of it. I did not breathe freely until I visited Gegenbaur at Jena (June, 1860); my long conversations with him finally confirmed my conviction of the truth of Darwinism or transformism.”
It was, therefore, in the critical days immediately before or during the negotiations with Gegenbaur which led to his setting up as a private teacher at Jena. The names of Darwin and Jena unite chronologically in Haeckel’s life—two great names that were to bear him into the very depths of his career, and that have their roots in the same hour.
We may ask what it was in the book that “profoundly moved” the young student of the radiolaria. The name of Braun only partly explains the matter, as Braun was an evolutionist of the same type as Bronn. He was amiably disposed to meet it, but did not openly enter on the new path. We must go deeper. We then understand it clearly enough, if we recollect Haeckel’s bent in the last few years.
He had no longer any scruples with regard to religion. The God of tradition had been entirely replaced in him by Goethe’s God, who did not stand outside of, but was one with, nature. “There is nothing within, nothing without: for what is within is without.” There was not a kernel, God, and a shell, Nature. “Nature has neither kernel nor shell: it is both together.”
The years spent in southern Italy had certainly helped to bring out as strongly as possible the contrast between Goethe’s conception and the conventional idea of God as an extramundane Creator. No surroundings are more apt to do this than the Romance peoples of the Mediterranean. In the northern, Protestant countries the ecclesiastical tradition of Deity has always a spiritual element, a kind of vague resolution into moral laws, that in some measure approach natural law, though one made by man. There is no trace of this in Naples and Sicily. The supernatural there is the saint, the madonna; they penetrate unceasingly into the natural reality, in every little detail of life and conduct. The antithesis of the poor cosmic machinery and the ever-present heavenly help and supersession of it is raised to a supreme height in the popular belief. Miracles are not relegated to earlier days and ancient books. They are expected, affirmed, and believed every day. The saint fills the net of the fisherman as he chases the edible cuttle-fishes by torchlight. The saint makes the storm that threatens the boat—makes it suddenly out of nothing. The madonna can arrest in a second the glowing stream of lava that rolls towards the village from Vesuvius, and if hundreds of them unite in ardent prayer and the making of vows, she will be appeased and do it. Every hair on a man’s head is twofold; there is the natural hair and a hair that can at any moment be changed, transformed, annihilated, or created afresh from nothing, by divine power. The man who has lived in this atmosphere of practical Dualism for years must be saturated to his innermost being with a feeling of the absolute contradiction between this conception of God and nature and Goethe’s philosophy. If he is to follow Goethe, this ancient extramundane, ever-interfering Deity must be given up without the least attempt at compromise.
Thus Haeckel’s position was incomparably more radical than Darwin’s from the very first. He no longer believed in a Creator, either in whole or part.
He asked himself, therefore, how he could now explain certain things in nature. He had learned from the great Johannes Müller that species were unchangeable, and it was impossible to conceive the spontaneous generation of the living from the dead. The essence, the predominant element of the living thing was the mysterious, purposive “vital force.” The first of these three ideas of the master’s to be surrendered entirely by him was the vital force. Even in Müller’s lifetime, and in his own laboratory, so to say, his pupil, Du Bois-Reymond, made the first great breach in the doctrine with his famous study of animal electricity, a really pioneer piece of work, especially as regards method, at that time. It was now more than ever probable that there was no more a special vital force besides the simple natural forces than there was a God distinct from nature. The animal or the plant was a wonderful outcome of the same laws that had built the crystal or the globe. The sharp distinction between living and dead matter fell into the waste-basket, where so many other Dualistic tags lay, cut off by the shears of science.
But if one of Müller’s theses was abandoned, another was retained as a real blessing with all the more tenacity by his pupils—the thesis that even the scientific investigator shall always “think”—nay, even “philosophise.” Müller called it “using one’s imagination,” in his desire to emphasise it. Now it was certainly a fair philosophic deduction from Du Bois-Reymond’s discoveries that one ought no longer to be so rigid as regards the possibility of spontaneous generation. If the same natural forces are at work in the organic and the inorganic, the living and the dead, it is no longer inconceivable theoretically that life and inorganic matter only differ in degree, not in kind. The distinction might become so slender—either now, or at least in past times—that an apparent “spontaneous generation” might really take place.