The Wonders of Life: A Popular Study of Biological Philosophy. Ernst Haeckel

often bound up with consciousness; we must rather descend the long scale of the development of consciousness until we reach the simplest protists, the monera (chapter ix.). The psychic activity of these homogeneous particles of plasm (for instance, the chromacea) rises very little above that of crystals; as in the chemical synthesis in the moneron, so in crystallization we are bound to assume that there is a low degree of sensation (not of consciousness), in order to explain the orderly arrangement of the moving molecules in a definite structure.

      The prejudice against theoretical materialism (or materialistic monism) which still prevails so much is partly due to its rejection of the three central dogmas of dualist metaphysics, and partly to a confusion of it with hedonism. This practical materialism in its extreme forms (as Aristippus of Cyrene and the Cyrenaic school, and afterwards Epicurus, taught it) finds the chief end of life in pleasure—at one time crude, sensual pleasure, and at others spiritual pleasure. Up to a certain point, this thirst for happiness and a pleasant and enjoyable life is innate in every man and higher animal, and so far just; it only began to be censured as sinful when Christianity directed the thoughts of men to eternal life, and taught them that their life on earth was only a preparation for the future. We shall see afterwards, when we come to weigh the value of life (chapter xvii.), that this asceticism is unjustifiable and unnatural. But as every legitimate enjoyment can become wrong by excess, and every virtue be turned into vice, so a narrow hedonism is to be condemned, especially when it allies itself with egoism. However, we must point out that this excessive thirst for pleasure is in no way connected with materialism, but is often found among idealists. Many convinced supporters of theoretical materialism (many scientists and physicians, for instance) lead very simple, blameless lives, and are little disposed to material pleasures. On the other hand, many priests, theologians, and idealist philosophers, who preach theoretical idealism, are pronounced hedonists in practice. In olden times many temples served at one and the same time for the theoretic worship of the gods and for practical excesses in the way of wine and love; and even in our day the luxurious and often vicious lives of the higher clergy (at Rome, for instance) do not fall far short of the ancient models. This paradoxical situation is due to the special attractiveness of everything that is forbidden. But it is utterly unjust to extend the natural feeling against excessive and egoistic hedonism to theoretical materialism and to monism. Equally unjust is the habit, still widely spread, of depreciating matter, as such, in favor of spirit. Impartial biology has taught us of late years that what we call "spirit" is—as Goethe said long ago—inseparably bound up with matter. Experience has never yet discovered any spirit apart from matter.

      On the other hand, pure dynamism, now often called energism (and often spiritualism), is just as one-sided as pure materialism. Just as the latter takes one attribute of substance, matter, as the one chief cause of phenomena, dynamism takes its second attribute, force (dynamis). Leibnitz most consistently developed this system among the older German philosophers; and Fechner and Zöllner have recently adopted it in part. The latest development of it is found in Wilhelm Ostwald's Natural Philosophy (1902). This work is purely monistic, and very ingeniously endeavors to show that the same forces are at work in the whole of nature, organic and inorganic, and that these may all be comprised under the general head of energy. It is especially satisfactory that Ostwald has traced the highest functions of the human mind (consciousness, thought, feeling, and will), as well as the simplest physical and chemical processes (heat, electricity, chemical affinity, etc.), to special forms of energy, or natural force. However, he is wrong when he supposes that his energism is an entirely new system. The chief points of it are found in Leibnitz; and other Leipzig scientists, especially Fechner and Zöllner, had come very close to similar spiritualistic views—the latter going into outright spiritism. Ostwald's chief mistake is to take the terms "energy" and "substance" to be synonymous. Certainly his universal, all-creating energy is, in the main, the same as the substance of Spinoza, which we have also adopted in our "law of substance." But Ostwald would deprive substance of the attribute of matter altogether, and boasts of his Refutation of Materialism (1895). He would leave it only the one attribute, energy, and reduce all matter to immaterial points of force. Nevertheless, as chemist and physicist, he never gets rid of space-filling substance—which is all we mean by "matter"—and has to treat it and its parts, the physical molecules and chemical atoms (even if only conceived as symbols), daily as "vehicles of energy." Ostwald would reject even these in his pursuit of the illusion of a "science without hypotheses." As a fact, he is forced every day, like every other exact scientist, to assume and apply in practice the indispensable idea of matter, and its separate particles, the molecules and atoms. Knowledge is impossible without hypotheses.

      Monism is best expressed as hylozoism, in so far as this removes the antithesis of materialism and spiritualism (or mechanicism and dynamism), and unites them in a natural and harmonious system. Our monistic system has been charged with leading to pure naturalism; one of its most vehement critics, Frederick Paulsen, attaches so much importance to this stricture that he thinks it as dangerous as dogmatic clericalism. We may, therefore, usefully consider the idea of naturalism, and point out in what sense we accept it and identify it with monism. The key to the position is in our monistic anthropogeny, our unprejudiced conviction, supported by every branch of anthropological research, of "man's place in nature," as we have established it in the first section of the Riddle (chapters ii.-v.). Man is a purely natural being, a placental mammal of the order of primates. He was phylogenetically evolved in the course of the Tertiary Period from a series of the lower primates (directly from the anthropoid apes, but earlier from the cynocephali and lemures). Savage man, as we have him to-day in the Veddah or Australian negro, is physiologically nearer to the apes than to highly civilized men.

      Anthropology (in the widest sense) is only a particular branch of zoology, to which we must assign a special position on account of its extreme importance. Hence all the sciences which relate to man and his psychic activity—especially what are called the moral sciences—must be regarded from our monistic point of view as special branches of zoology and as natural sciences. Human psychology is inseparably connected with comparative animal psychology, and this again with that of the plants and protists. Philology studies in human speech a complicated natural phenomenon, which depends on the combined action of the brain-cells of the phronema, the muscles of the tongue, and the vocal cords of the larynx, as much as the cry of mammals and the song of birds do. The history of mankind (which we, in our curious anthropocentric mood, call the history of the world), and its highest branch, the history of civilization, is connected by modern prehistoric science directly with the stem-history of the primates and the other mammals, and indirectly with the phylogeny of the lower vertebrates. Hence, when we consider the subject without prejudice, we do not find a single branch of human science that passes the limits of natural science (in the broadest sense), any more than we find nature herself to be supernatural.

      Just as monism, or naturalism, embraces the totality of science, so on our principles the idea of nature comprises the whole scientifically knowable world. In the strict monistic sense of Spinoza the ideas of God and Nature are synonymous for us. Whether there is a realm of the supernatural and spiritual beyond nature we do not know. All that is said of it in religious myths and legends, or metaphysical speculations and dogmas, is mere poetry and an outcome of imagination. The imagination of civilized man is ever seeking to produce unified images in art and science, and when it meets with gaps in these in the association of ideas it endeavors to fill them with its own creations. These creations of the phronema with which we fill the gaps in our knowledge are called hypotheses when they are in harmony with the empirically established facts, and myths when they contradict the facts: this is the case with religious myths, miracles, etc. Even when people contrast mind with nature, this is only a result, as a rule, of similar superstitions (animism, spiritism, etc.). But when we speak of man's mind as a higher psychic function, we mean a special physiological function of the brain, or that particular part of the cortex of the brain which we call the phronema, or organ of thought. This higher psychic function is a natural phenomenon, subject, like all other natural phenomena, to the law of substance. The old Latin word natura (from nasci, to be born) stands, like the corresponding Greek term physis (from phyo—to grow), for the essence of the world as an eternal "being and becoming"—a profound thought! Hence physics, the science of the physis, is, in the broadest sense of the word, "natural science."

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