But now the question arises: does the search after these agencies henceforth remain the exclusive task of natural science, and have we therefore simply to wait and see whether it will succeed in finding them? or have we to look for the answer to these questions, which natural science can no longer give, in another science—namely, philosophy? The first question we will have to answer in the affirmative, the second in the negative. It is certainly understood that metaphysical principles must underlie all physical appearances; and the right to define these principles, so far as they can be known, is willingly conceded to philosophy by the scientists, with the exception of those of materialistic and naturalistic tendencies. This mutual re-approaching of philosophy and natural science is one of the most gratifying, and, to both, most fruitful evidences of the intellectual work of the present generation. But these metaphysical principles themselves become cognizable only when the physical effects, whose cause they are, become accessible to our knowledge; and every attempt to find them a priori, or only to extend them a priori, will always fail through the opposition of empirical facts; or even if this attempt accommodates itself to the existing state of knowledge at a given time, it will always be overcome by the {110} progress of the empirical sciences. In the most favorable case, it can claim the value of a hypothesis which has to be put to the proof, whether it can be empirically confirmed and whether we can successfully operate with it in knowing the world of realities. But herewith it leaves the realm of pure philosophy, and makes the question of its right to exist dependent upon the decision of natural science.

Since the decline of the doctrines of nature held by Schelling, Steffens, and Hegel, there has come to our knowledge, from the domain of philosophy, but one earnest attempt to explain the origin and development of organisms down to the concrete differences between single types, classes, and even orders and families, from one single metaphysical principle; and this attempt has been made by an antagonist of the descent doctrine. K. Ch. Planck, in "Seele und Geist, oder Ursprung, Wesen und Thaetigkeitsform der physischen und geistigen Organisation von den naturwissenschaftlichen Grundlagen aus allgemein fasslich entwickelt" ("Soul and Spirit, or Origin, Nature, and Form of Activity of Physical and Intellectual Organization, Clearly Developed from a Scientific Basis"), Leipzig, Fues, 1871, and in "Wahrheit und Flachheit des Darwinismus" ("Truth and Platitude of Darwinism"), Noerdlingen, Beck, 1872, makes the "inner concentration" the moving principle of the whole development of the world. He thinks that what belongs to the organism and to the soul has originated and developed up to man and his spiritual nature thus: that the creating centrum of the earth produces individual centra on its periphery, which tend more and more to bring into view the principle of {111} centralization, in its contrast to the purely peripheral form of existence, until it reaches its goal in man, with his centralizing spirit. We have no reason to reject the idea of a principle of concentration in the world and its parts; it is confirmed by observation, and shows itself fruitful in many respects. But in spite of the many ingenious and often suggestive ideas in the works of Planck, we have some doubt about a system which tries to explain the whole concrete abundance of the richness of formations and life-forms in the world, rising higher and higher up to spiritual existence and moral action, from the single idea of concentration, and makes this principle the mystical and mysteriously acting cause of a whole world and its contents. We doubt at the outset the success of this argument. We have especially the strongest objections to a philosophical system which submits all the contending physical theories of the present to the measure of that concentration principle, and from these purely metaphysical reasons takes side exclusively with the one or the other of the theories, or establishes new theories—from the theories of atoms and ether, of light and heat, down to geological questions as to whether universal revolutions of the world or a continual development took place. The solution of all these questions, in their full extent, we do not attribute to philosophy, but to natural science; although to a natural science which permits philosophy to define the ideas with which it operates and the general principles to which it comes. For this renunciation—which philosophy, however, can not at all escape—it will be the more richly rewarded in this, that it obtains the more certainly for its own work sure and sifted material. But all attempts which can not {112} submit to this renunciation, give only an apparent right to that view which Albert Lange, in his "History of Materialism," defends, when he banishes speculative philosophy to the realm of imagination.

But in rejecting philosophy in the question of the causes of the development and organization of the organic kingdoms, we did not reach the end of the philosophic problems with which we are confronted. This whole question is itself only a segment of the problems before which we stand, and leads of necessity to other questions.

Already within the series of development of the organic world, so far as it is investigated by natural science, we have found and named a point (at the end of Sec. 1, Chap. II, Book I), where the competency of pure natural science comes to an end, and the question arises whether another source of knowledge—i.e., even philosophy—can not take up the investigation where natural science completes its task. This point was the origin of self-consciousness and of free moral self-determination; consequently, the origin of that which makes man man. Going still farther back on the temporal and ideal scale of organic beings, we arrive at another point, which natural science no longer can explain, and that is the origin of sensation and of consciousness. With the appearance of sensation and consciousness, the animal world came into existence. Moreover, the whole scientific question as to the origin and development of species, so far as we have hitherto treated it, started from initial points where the organic and life already existed; it, therefore, leads of necessity to the further question as to the origin of the organic and of life itself. D. F. Strauss, {113} in his "Postscript as Preface," thus clearly and simply characterizes these still unfilled blanks in the evolution theory: "There are, as is well known, three points in the rising development of nature, to which the appearance of incomprehensibility especially adheres (to speak more categorically: which have not been explained thus far by anybody). The three questions are: How has the living sprung from that which is without life? the sentient (and conscious) being from that which is without sensation? that which possesses reason (self-consciousness and free will) from that which is without reason?—questions equally embarrassing to thought." But even the question as to the origin of the organic and of life can not be discussed without an investigation, leading us farther back to the question as to the elements of the world in general. The doctrine of atoms, and the mechanical view of the world, are the scientific evidences of the efforts in this direction.

So far as the attempts to solve these four questions start from the results of natural science and, from this starting-point of the known, try to solve the unknown, we will have to assign them in the encyclopaedic classification of the sciences, to that department of philosophy which treats the doctrines of nature; and since our whole investigation starts from the Darwinian theories, and only tries to treat of what is properly connected with them, the attempts to solve these four questions offer themselves as the naturo-philosophic supplements of the Darwinian-theories.

After concluding our treatment of them, we shall have to speak of still another view, which presupposes all these attempts at solution to be wholly or nearly {114} successful, and draws an inference from them which no longer belongs to the realm of natural science, but is a purely metaphysical hypothesis; it is the abolition of the idea of design in nature. In connection with this, finally, we shall have to discuss the name which this view has lately assumed, viz: "Monism."

Whatever further questions may arise, belong either to the special subdivisions of natural science and philosophy, or to theological and ethical problems.

* * * * * {115}

CHAPTER I.

THE NATURO-PHILOSOPHIC SUPPLEMENTS OF THE DARWINIAN THEORIES.

Sec. 1. The Origin of Self-Consciousness and of Free Moral Self-Determination.

If sensation, and its most developed form, consciousness, is a reflex of the material in something immaterial, which feels itself a unit in contrast to the material, and, where sensation rises into consciousness, is opposed as a unit to the material—self-consciousness again is the reflex of this sentient and conscious subject in a new and still higher immaterial unity; and this again makes this sentient and conscious subject, together with the sum of its feelings and ideas, its object, changing it from a sentient and conscious subject into a felt and presented object. Therefore it is clear, and will be the result of all thought upon these concepts, that as with sensation and consciousness, so also with self-consciousness, something new always comes into existence—a higher category of being, different from the merely material. The first is the form of being of the animal world; the latter that of mankind.

It is exactly the same with the first appearance of voluntary movement, and again with that of free moral self-determination. The reaction of the sentient subject upon his sensations is something qualitatively different from the purely mechanical and physical action and {116} reaction of pure matter; although, in order to understand the possibility of a sensation as well as of a voluntary movement, we must admit that the physical qualities of matter must be such as to afford a basis and condition for sentient and reacting beings. That reaction is the reaction of something immaterial upon the material, even if it is entirely caused by the material and bound to the material. Now, with free moral self-determination a new subject comes into existence and activity in the individual, which makes that subject, reacting upon mere sensations and ideas, its object, and, as a new immaterial subjective unity, acts determiningly upon that subject which has just become object. This new subject, considered from the side of its receptivity, we call self-consciousness; from the side of its spontaneity, free moral self-determination. Whether we consider this freedom predetermined or not, does not at all alter the described fact and the qualitative difference between the form of human moral agency and that of purely animal spontaneity. For even those advocating determination must admit that the morally acting subject distinguishes itself from its object, and does not take its motives to action from the material and from the instinctive life which is bound to the sensual and dependent on it.

Now it is true that all these circumstances in organized individuals which serve self-consciousness and free moral self-determination as their condition, presupposition, and basis, all the dispositions of the soul and the manifestations of life found in the animal world, will be worthy of the closest attention even on this account: because they form the basis, the condition, and (if self-consciousness and freedom are once present) an essential {117} part of the contents and object of self-consciousness and moral self-determination. But where the origin of man is discussed, the central point of the investigation is no longer the enumeration of those activities of the soul of man whose analogies we also find in the animal world, but rather in the answer to the question as to how that entirely new manifestation, self-consciousness and moral self-determination, came into existence or could have originated. This question is the more decidedly the central point of the investigation, since this new form, when once in existence, has for its object not only what already appears in the life of the soul of animals, but also receives a new object, which can only be an object of self-consciousness and of moral self-determination, and not of mere consciousness and instinctive life. These new objects are the ideas leading up to the conception of God and moral ideals.

Now this very question as to the origin of self-consciousness and of free moral self-determination is wholly misjudged as to its importance, and given remarkably little attention by those evolutionists who are well versed in the realm of natural science. The question as to the origin of self-consciousness is either entirely ignored—as if self-consciousness must originate wholly by itself, if only those first steps of an intellectual and social life which the animal world also shows, are once present and properly developed—or the solution is put aside with the most superficial analogies. The question regarding free moral self-determination, on the other hand, is either likewise ignored, and for the same reasons, or it is supposed that it must fail of itself, if {118} only this self-determination is explained in a deterministic way.

It is true, Darwin devotes several chapters of his work, "Descent of Man," to a comparison of the intellectual powers of man with those of animals, and these chapters are full of the most interesting facts and comparisons; but although his work comprises two volumes, he devotes to the origin of self-consciousness, individuality, abstraction, general ideas, etc., only a single page, and justifies his brief treatment with the assertion that the attempt at discussing these higher faculties is useless, because hardly two authors agree in their definitions of these terms. What he says about self-consciousness is really contained in two sentences, namely: "But how can we feel sure that an old dog with an excellent memory and some power of imagination, as shown by his dreams, never reflects on his past pleasures or pains in the chase? This would be a form of self-consciousness." On the other hand, as Buechner has remarked in his "Lectures about Darwin's Theory": "How little can the hard-working wife of a degraded Australian savage, who hardly ever uses abstract words, and can not count above four, how little can such a woman exert her self-consciousness, or reflect on the nature of her own existence!" And in Darwin's resume of his chapters on the intellectual powers of man and animals, he says, on page 126: "If it could be proved that certain high mental powers, such as the formation of general concepts, self-consciousness, etc., were absolutely peculiar to man, which seems extremely doubtful, it is not improbable that these qualities are merely the incidental results of other highly-advanced intellectual faculties: {119} and these again mainly the result of the continued use of a perfect language."

If Darwin is thus not able to show us in the animal world a single real analogy which at all approaches self-consciousness, and, in order to supply this want, must have recourse to the purely hypothetical possibility that it is not certain whether an old hunting-dog does not reflect upon the past joys of the chase; if by the uncertainty of the expression that self-consciousness might be an "accompanying" result of other faculties, he nevertheless gives us to understand that he can not find the sufficient cause of the origin of self-consciousness in those other faculties; and, finally, if he closes the last mentioned quotation with a sentence which has for its premise the wholly illogical thought that language might have been able to reach "a high state of development" before the origin of self-consciousness and without its assistance: then, indeed, the result of all this certainly is that he has given no adequate consideration to the specific nature of self-consciousness. It is only under this supposition that it is possible for him to say: "Nevertheless, the difference in mind between man and the higher animals, great as it certainly is, is one of degree and not of quality." The authors may possibly not agree in the definitions of the idea of self-consciousness—we ourselves perhaps are only an additional example in confirmation of this fact—; but whatever the definition may be, the fact itself remains, that self-consciousness does not stand as one of the intellectual faculties beside the others and cooerdinate with them, but, as an entirely new form of being, introduces a qualitatively new and valuable factor into the subject. That which precedes the {120} origin of self-consciousness—the purely conscious and not yet self-conscious life of the soul, as it shows itself with higher animals, especially with mammals—may have been the necessary condition and requirement for the origin of self-consciousness. It certainly has been so; and from this point of view, all these psychological studies of animals and psycho-physical investigations which are a favorite object of modern science, have a high value; but what has been called into existence by means of conditions is not on that account the product of those conditions. This very fact is one of the greatest mistakes of most of the modern evolution theories: that very often—and especially where they wish to draw metaphysical conclusions from their scientific results or hypotheses—they confound condition and basis with cause.

Now it appears to us that, in quite an analogous way, Darwin overlooks or contests the fact that with free moral self-determination something specifically new comes into existence. He certainly discusses the origin of the moral qualities of man more in detail than he does the origin of his intellectual qualities. He derives them, in their first beginnings, from the fixity, transmission and increase of the social impulses and instincts. These, being the basis of the whole moral development, and leading in their more mature form to love and to sympathy, originated by natural selection; and the other moral qualities, such as moral sense and conscience, progressed more by the effect of custom, by the power of reflection, instruction, and religion, than by natural selection. Higher and lower, common and special, permanent and transitory instincts come into collision {121} with one another. The dissatisfaction of man when any of the lower, special, and transitory instincts have overcome the higher, common and permanent, and the resolution to act differently for the future, is conscience. Darwin considers that one a moral being who is capable of comparing with one another his past and future actions and motives, of approving some of them and of disapproving others; and the fact that man is the only creature who can with certainty be ranked as a moral being is, according to Darwin, the greatest of all differences between man and animals.

Here, again, the whole central point of the investigation as to the origin of man does not lie in the question of the origin of the instincts between which the moral subject, acting in moral self-determination, has to choose. For it is clear that the beginnings of these instincts are also present in the animal world. But the main question is, how did this faculty and necessity of choosing, this conscience and responsibility, this "moral sense," as Darwin calls it, originate? Now to this question we have a plain answer in the before-mentioned utterances of Darwin: It originated not as a product of the social instincts—it only has these instincts for its preceding condition, object and instrument; but it originated as a product of other agencies, which act upon these impulses and instincts, operate with them, choose between them; and as these other agencies Darwin mentions the high development of the intellectual powers. That this is his opinion, we can clearly see from an expression with which he introduces his essay on the origin of "moral sense": "The following proposition seems to me in a high degree probable—namely, that {122} any animal whatever, endowed with well-marked social instincts, would inevitably acquire a moral sense or conscience, as soon as its intellectual powers had become as well, or nearly as well developed, as in man." These intellectual powers which moral feeling and conscience require at their birth, are certainly, according to Darwin the power to distinguish oneself as subject from one's impulses and instincts, and to choose between them; i.e., self-consciousness. We shall have to admit fully this intimate connection between moral self-determination and self-consciousness; but we must admit, at the same time, that moral self-determination—this new form of activity in which moral activity distinguishes itself from all merely instinctive activity—finds its sufficient explanation in the previous stage of the animal world as little as self-consciousness; and that moral self-determination has the condition and presupposition, but not the cause, of its existence in that which is also found in the previous stage of the animal world. The proof that the origin of moral self-determination finds its sufficient explanation in that which the previous stage of the animal world also has, would appear to have been given by Darwin only when he had succeeded in explaining the origin of self-consciousness from animal intelligence; but that he did not succeed in it, we think we have clearly shown. On the other hand, we willingly admit that the study of the social and all other instincts and impulses which are common to man and animals, and which in man form the object and instrument of his moral activity, has for us the highest interest, inasmuch as the only problem is to explain the conditions and prerequisites of moral self-determination—or, historically speaking, the conditions {123} and prerequisites of the origin of morally acting beings. Furthermore we have to say here also that condition and prerequisite are not identical with cause, and it is precisely the cause of moral responsibility and of the origin of such morally responsible beings, which has not yet been discovered by the Darwinian theory.

The followers of Darwin enter still less into the discussion of the question as to the origin of self-consciousness and of moral self-determination. Haeckel—who, in his "Natural History of Creation" and in his "Anthropogeny," expounds his whole evolution theory in all its antecedent conditions and consequences—has, indeed, much to say of the different faculties of the soul of man and animals. He traces these faculties in the case of man down to the lowest state of the most degraded races, and in the case of animals from the kermes up to the bee, from the lancelet-fish to the dog, ape, elephant and horse; and he also treats of the so-called a priori knowledge which "arose only by long-enduring transmission, by inheritance of acquired adaptations of the brain, out of originally empiric or experiential knowledge a posteriori," (Vol. II, 345). But we look in vain in his works for a treatment of the question as to the origin of the Ego—of self-consciousness. Nowhere does he enter into the analysis of the psychological ideas; he only compares the psychical utterances of different creatures, and thinks the whole problem solved when he says: "The mental differences between the most stupid placental animals (for instance, sloths and armadillos) and the most intelligent animals of the same group (for instance dogs and apes) are, at any rate, much more considerable than the differences in the {124} intellectual life of dogs, apes, and men." Or: "If these brutish parasites are compared with the mentally active and sensitive ants, it will certainly be admitted that the psychical differences between the two are much greater than those between the highest and lowest mammals—between beaked animals, pouched animals and armadillos, on the one hand, and dogs, apes, men, on the other." The fact that in the human individual consciousness and self-consciousness are gradually developed, is to him a proof that in the organic kingdom also consciousness and self-consciousness came into existence gradually, and, indeed, hand-in-hand with the development of the nervous system; and with this result he thinks that he has relieved himself from the task of showing the "how" of the origin of self-consciousness. This becomes clearly evident from a remark about the origin of consciousness, in his "Anthropogeny," where he says that, if DuBois-Reymond had thought that consciousness is developed, he would no longer have held its origin to be a thing beyond the limits of human capacity. Haeckel likewise seems to regard the question of the origin of moral self-determination as solved or rejected, if only freedom is denied—which, indeed, is repeatedly done by him.

A similar defect in the treatment of this question by evolutionists we find in the works of Oscar Schmidt, Gustav Jaeger, and others. Even Emil DuBois-Reymond, who, in his celebrated and eloquent lecture on "The Limits of the Knowledge of Nature," given before the assembly of scientists at Leipzig, 1872, asserts so energetically that the origin of sensation and consciousness is inexplicable (see next section), seems to {125} take the origin of self-consciousness for granted, and as needing no further explanation, if only consciousness is once present.

Since, then, the scientists leave us without a sufficient answer to the question respecting the origin of self-consciousness and of moral self-determination, we shall have to turn to the philosophers. Here, indeed, we find rich definitions and genetic analyses, but none that lead us any farther than to the information that consciousness is the necessary condition of self-consciousness; that animal instinct is the necessary antecedent condition of moral self-determination. Yet in the works of these very philosophers who are inclined to a mechanical and "monistic" view of the world, we find that they directly avoid the question as to the origin of self-consciousness and of moral self-determination. As soon as they are led near it, in the course of reasoning in their works, they suddenly turn aside again to the quite different questions of the connection between brain and soul, between physical and psychical, external and internal processes, etc. Evidently they feel that with this question they have arrived at the weak point of their system. That here is a weak point, we clearly see in the case of D. F. Strauss, a leading advocate of modern naturalism, and the greatest philosophic scholar of that school. It is true, in his "Postscript as Preface," as we saw before, he mentions the origin of self-consciousness as one of the points which need special explanation; but he seems to have made this acknowledgment more with the purpose of showing that DuBois-Reymond, in admitting the origin of self-consciousness to be explainable, has no longer any reason to contest the explicability of the {126} origin of sensation and consciousness; for in his work on "The Old Faith and the New," he did not enter into that question at all. On the other hand, he makes in his last-mentioned work a remarkable confession. In answering the question—how do we determine our rule of life?—he comes to speak of the position of man in nature, traces a law of progress in nature, and says: "In this cumulative progression of life, man is also comprised, and, moreover, in such wise that the organic plasticity of our planet (provisionally, say some naturalists, but that we may fairly leave an open question) culminates in him. As nature can not go higher, she would go inwards. 'To be reflected within itself,' was a very good expression of Hegel's. Nature felt herself already in the animal, but she wished to know herself also." But still stronger is the following expression: "In man, nature endeavored not merely to exalt, but to transcend herself." In Sec. 1, Chap. II, we shall have to speak of this important acknowledgment of teleology in nature, which such an antagonist of teleology as Strauss makes in the above-quoted remarks about a progress in nature and a will of nature; but here we are more interested in the equally remarkable acknowledgment of the fact that man can not be explained from nature alone—that he is something which transcends nature. For that (according to Strauss) nature, in originating man, not only intended to transcend herself, but really did transcend herself and, that she succeeded in her intention, we can infer from the moral precept which Strauss gives: "Do not forget for a moment, that thou art human; not merely a natural production."

The result of our investigation, therefore, is that {127} with self-consciousness and free moral self-determination something specifically new came into existence which had its antecedent condition in a previous state of existence, but has not yet found its sufficient explanation in this antecedent state.

Sec. 2. The Origin of Sensation and of Consciousness.

The limits of our knowledge show themselves still more clearly in the attempts to explain the origin of consciousness and its lowest form—sensation. Self-consciousness is without doubt ideally nearer to consciousness in this, that both are an immaterial activity; and yet we found no demonstrable bridge which leads from consciousness to self-consciousness. Still broader is the gulf between the material and the immaterial, between the unconscious and the conscious,—or, to describe the two realms with names which bring them nearest together, between that which is without sensation and that which has sensation: a gulf to bridge which philosophy also has vainly exerted its utmost efforts, as has been well known since the "supernatural assistance" of Descartes and the "preestablished harmony" of Leibnitz. Wherein lies the real necessity that there should be sensation? How does the material become something that is felt? What is the demonstrable cause (not the condition, but the cause) of a sentient subject? To these questions, every science up to the present day lacks an answer. As is well known, DuBois-Reymond, in his previously-mentioned lecture upon "The Limits of our Knowledge of Nature," declares the origin of sensation and of consciousness to be one of two limits, beyond {128} which we have not only to say "ignoramus," but "ignorabimus."

In abstracto, we might think of two attempts at bridging over this gulf: the first one is that we try to transform sensation itself into something material, and the other is that we attribute sensation also to that which, according to our observation, seems to be without sensation; namely, to matter and its elements, the atoms. Both of these attempts have been made—the former by D. F. Strauss in his "The Old Faith and the New," and by the English philosopher, Herbert Spencer, in his "First Principles of Philosophy;" the latter, first pointed out by Schopenhauer, was taken up and farther developed by Zoellner in his work, "Ueber die Natur der Kometen" ("Nature of the Comets"), Leipzig, Engelmann, 1872, and with special acuteness by an "Anonymus" in the work: "Das Unbewusste von Standpunkt der Physiologie und Descendenztheorie" ("The Unconscious from the Standpoint of Physiology and Descent Theory"), Berlin, Duncker, 1872.

Strauss says, in the previously-mentioned work: "If, under certain conditions, motion is transformed into heat, why may it not, under other conditions, be transformed into sensation?" And Herbert Spencer says, in his "First Principles of Philosophy," (page 217): "Various classes of facts thus unite to prove that the law of metamorphosis, which holds among the physical forces, holds equally between them and the mental forces. Those modes of the unknowable which we call motion, heat, light, chemical affinity, etc., are alike transformable into each other, and into those modes of the unknowable which we distinguish as sensation, {129} emotion, thought: these, in their turns, being directly or indirectly retransformable into the original shapes."

But motion—even the finest material motion, that of ether, (which, in consequence of the very important discovery of the conservation of force and of the mechanical equivalent of heat, made by Robert von Mayer, at present is taken to be heat)—is so decidedly a material process, the sensation of motion is so decidedly a reflex of the material in something immaterial, that the assertion of a transformation of motion into sensation seems to us only to change the point of view, and not to explain the difference, but to efface it. And we think that the appeal of Strauss from his contemporaries, who do not understand him, to posterity, who would understand him better and esteem him, has but little prospect of being operative.

If that which has sensation and that which has it not, are to be brought genetically near one another, and hence the difference between the two at the point where the lowest sentient being has found its first existence, is to be made void or at least bridged over, then it is much more reasonable, and also in the line of Strauss's solution, to deny the difference between that which has sensation and that which has it not, and to do this in the sense in which we also declare that to be sentient which we have hitherto been accustomed to regard as without sensation; and we should likewise attribute sensation to the original elements of the world, be they called atoms or whatever one may wish. This is done by Zoellner and by the before mentioned "Anonymus." This conclusion is logical; it is even the only possible conclusion, if we once start from the axiom that the new, which comes {130} into existence, must necessarily be explainable from agencies previously active, and known to or imagined by us through abstractions and hypotheses. Zoellner is certainly right when, in his work which appeared before the lecture of DuBois-Reymond, he puts the alternative, "either to renounce forever the conceivableness of the phenomena of sensation, or hypothetically to add to the common qualities of matter one more, which places the simplest and most elementary transactions of nature under a process of sensation, legitimately connected with it;" as also when he says (page 327): "We may regard the intensity of these sensations (of matter) as little and unimportant as we wish; but the hypothesis of their existence is, according to my conviction, a necessary condition, in order to comprehend the really existing phenomena of sensation in nature." Only we shall do well to choose the first alternative for the present, and, with DuBois-Reymond, answer the question as to the explanation of the origin of sensation with an "ignoramus"; indeed, we shall take a surer road with his "ignorabimus" than by a plunge into that bottomless ocean of hypotheses—in spite of the protest of Haeckel, who (Anthrop., page XXI) sees that scientist who has the courage to admit the limits of our knowledge, on account of this "ignorabimus", walking in the army of the "black International", and "marshalled under the black flag of the hierarchy," together with "spiritual servitude and falsehood, want of reason and barbarism, superstition and retrogression", and fighting, "spiritual freedom and truth, reason and culture, evolution and progress." For a solution of the question which simply denies all sharply-marked differences in the world, and explains {131} the new, which comes into existence with sensation, by the assertion that this new element is not new, but was already present, and that it exists everywhere, only we do not see it everywhere,—such a solution seems to us not to be the true way to interpret the problem of the sphinx. Even Ed. von Hartmann seems to infringe the impartiality of the true observer, when, in his "Philosophy of the Unconscious," he attributes sensation to plants. But when Zoellner says (p. 326): "All the labors of natural beings [and, as the connection indicates, of all, even of inorganic natural beings] are determined by like and dislike;" and when "Anonymus" attributes sensation to all atoms and to all complexities composed of them, even to stone, then all reasonable conception of natural things and processes certainly vanishes into thin air.

It will be remembered, however, that in treating the question of the origin of self-consciousness, although we were not able to solve the problem, nevertheless we had to ascribe high value to the investigation of all psychical processes on the low stage of sensation and consciousness, since they show us not the cause, but the condition and basis, of self-consciousness. Likewise, in the question as to the origin of sensation and of consciousness, although we are not able to solve it, we will willingly admit that we observe, even in that which has no sensation, qualities and processes which furnish the absolutely necessary condition and basis for sensation. For the same reason, we will also admit the manifold analogies of sensation which we observe in that which is without sensation. The whole system of symbols in nature which fills our treasury of words and penetrates, in a {132} thousandfold way, our scientific and popular, our poetical and prosaic speech, our thoughts and feelings, bears witness to the fact that that which is without sensation is also a preparatory step to sensation, and feeling both active and passive springs from it. However, a preparatory step, as such, is not necessarily the cause; and the fact and the acknowledgment of a correlation is not on that account an explanation.

Sec. 3. The Origin of Life.

The third problem to be solved is the origin of life. As is well known, Darwin himself makes no attempt at explaining this problem, but is satisfied with the idea that life was infused into one or a few forms by the Creator ("Origin of Species," 6 ed., p. 429). His investigations and theories only begin where organic life, in its first and lowest forms, is already in existence.

But lately there have been made, in the realm of the organic, discoveries of beings which take the lowest conceivable round on the ladder of organisms, and which in their form and structure are so simple that from them to the inorganic there seems to be but a short step. We can no longer mention as belonging to the bridges which are said to lead from the organic world to the inorganic, the often-named bathybius, discovered by Huxley, and so strongly relied upon for the mechanical explanation of life—a slimy net-like growth, which covers the rocks in the great depths of the ocean. For after scientists like K. E. von Baer and others had already declared it probable that this bathybius is only a precipitate of organic relics, no less a person than the discoverer of the bathybius, in the "Annals of Natural History," 1875, {133} and in the "Quarterly Journal of Microscopical Science," 1875, has suggested that the whole discovery is but gypsum, which was precipitated in a gelatinous condition. Likewise the utterances concerning the simplicity and lack of structure of the lowest organisms, are to be accepted only with great reservation; for most of these organisms show very differently and very distinctly stamped structures; of this fact, anyone may easily convince himself, who has had the opportunity of observing with the microscope low and lowest organisms, and to admire their striking and manifold forms. Nevertheless, there are monera whose structure seems to be nothing but a living clod without kernel and cover, and which in that respect represent the lowest conceivable form of organic being and life.

Now, relying on these discoveries, as well as upon the successful demonstration, by inorganic means, of organic acids in chemistry, and starting from the supposition that the first appearance of life must necessarily be explained by those agencies which are already active in the inorganic nature, many scientists have attempted the so-called mechanical explanation of life. This attempt has been made most logically and systematically by Haeckel. He says that organic matter, organic form, and organic motion, in the lowest stages of the organic, which are almost the only ones to be taken into consideration when the problem of the origin of life is discussed, contain nothing at all which does not also pertain to the inorganic. In his opinion, organic matter is an albuminous carbon combination, of which we have to presuppose that, like all chemical combinations, under certain physical and chemical conditions it can also arise in the realm {134} of the inorganic in a purely chemical and mechanical way. Organic form which, in its lowest stages, is so simple, like the moneron and the bathybius, and which stands still lower than a cell, is, moreover, something which there is no difficulty in explaining from inorganic matter. Finally, organic motion which alone is the last and lowest characteristic of the organic in its lowest stage—in which the process of life properly consists, and in which, therefore, we have to recognize the punctum saliens of the whole question—is only an increase and complication of the merely mechanical motion of the inorganic, likewise explainable by mechanical causes. This view Haeckel expounds in the thirteenth and partly also in the first chapter of his "Natural History of Creation," and explains the origin of the first and most simple organic individuals either through what he calls autogony in an inorganic fluid, or through plasmogony in an organic fluid—a plasma or protoplasma. In fact, according to him, the only correct idea is that all matter is provided with a soul, that inorganic and organic nature is one, that all natural bodies known to us are equally animated, and that the contrast commonly drawn between the living and the dead world does not exist. This is but a repetition, in a more rhetorical way, of the same idea which "Anonymus" expressed in discussing the question as to the origin of sensation.

DuBois-Reymond—who, in his lecture at Leipzig, pronounced the origin of sensation and of consciousness a problem of natural science, never to be solved—is also of the opinion that the explanation of life from mere mechanism of atoms is very probable, and only a question of time. It is well known that the experimental {135} attempts at originating the organic through chemistry are at present pursued with an eagerness that can have its stimulus only in the hope of success.

It is clear that the main point of the question does not lie in organic matter or in organic form, but in organic motion, for even the specific of the organic form originates only first through organic motion of life. If, therefore, life is to be explained from mechanical causes, it must also be shown that the merely mechanical motion of inorganic matter produces that motion which we know as organic motion, and how it produces it. The idea of "increase and complication of the inorganic, merely mechanical motion," with which Haeckel throws a bridge from the living to the lifeless or from the organic to the inorganic, does not yet give us that proof; it seems rather to be one of those pompous phrases with which people hide their ignorance and make the uncritical multitude believe that the explanation is found: a manipulation against which, among others, Wigand, in his great work, repeatedly protests, as also does the Duke of Argyll in his lecture on "Anthropomorphism in Theology," having especially in his mind the deductions of Spencer. For we may review the whole known series of mechanical motions and their mechanical causes, and imagine their mechanical increase and their mechanical complication the largest possible; and still the life-motion of the organic will never result therefrom. If such a keen psychical and physiological investigator and thinker, and such an authority in the realm of the motions of atoms and molecules, as Gustav Theodor Fechner—"Einige Ideen zur Schoepfungs- und Entwicklungsgeschichte der Organismen" ("Some Ideas about the History of the {136} Creation and Development of Organisms"), Leipzig, 1873, p. 1, f.—can find the whole lasting and effectual difference between the organic and inorganic in nothing else than in the way and manner of motion—namely, that the motion of the organic molecules is different from that of the inorganic molecules—and when he traces this difference with mathematical exactness, then an assertion which simply denies that difference, without attempting to show the identity of the two motions, to say nothing of proving this identity, is nothing more than a clear evidence that the mechanical theory has not yet succeeded in explaining the origin of life, and that those scientists who so haughtily look down upon the abuse of "vital power," to the efficacy of which their antagonists began to resort when their knowledge came to an end, make exactly the same abuse with their "mechanism." That organic motion, even the organic motion of molecules, once present, comes into dependence on the well known laws of mechanism, we naturally will not deny; any more than that the human body, when serving the will of the mind, follows in its motions the laws of physiology and mechanism.

Preyer seems to make a mistake similar to that of those who efface sensation and motion, when, in an essay on the hypothesis of the origin of life, in the "Deutsche Rundschau," Vol. I, 7, he even effaces the difference between life and sensation, and simply identifies life and motion. "Self-motion, called life, and inorganic movement of bodies by agencies outside of themselves, are but quantitatively, intensively, or gradually different forms of motion; not in their innermost being different.... Our will changes many kinds of motion into heat, makes {137} cold metal to be red-hot simply by hammering.... Likewise inversely, as the law of the conservation of force must require, a part of the eternal heat of the metal can be now and forever transposed into the living motion of our soul." This whole manner of investigation and proof is one of those numerous unconscious logical fallacies which, introduced by Hegel, have gradually attained a certain title by possession. From the observation of a process, they abstract a characteristic, as general as possible,—as, for instance, from the observation of life the characteristic of motion; then they find that the process has the characteristic in common with still other processes—as, for instance, the self-motion of the living has the general characteristic of motion in common with the objective motion of the lifeless; and then they persuade themselves that the process which they try to explain is really explained by having found a quality of this process as comprehensive as possible. And in order to hide the falsity of the conclusion, they also give to the general idea, which they have found to be a characteristic of that process, the same name which the special process has,—as, for instance, they call motion life, no matter whether it is a motion of itself or a being moved, no matter whether it is performed from within or in consequence of an impulse from without; and then they say: "Behold, life is explained; life is nothing but motion." But it can be readily seen that life is also motion, and has therefore this characteristic in common with everything which is moved; but that the specific of that motion called life—namely, self-motion in consequence of an impulse renewing itself from within, and, as Fechner shows, {138} self-motion in a rotatory direction of the molecules, precisely the same thing which in distinction from other motions we call life,—is not explained, but simply ignored.

There is still another bold hypothesis which we have to mention—namely, that the organic germs were once thrown from other spheres upon the earth by aerolites. Years ago this idea was declared by Helmholtz to be scientifically conceivable; then it was formally asserted and brought into general notice by Sir William Thompson, in his opening address before the annual assembly of the British Association at Edinburgh, in 1871, but rejected as formally and materially unscientific by Zoellner, in the preface to his work, "Nature of Comets," and again defended by Helmholtz in his preface to the second volume of a translation of Thompson and Tait's Theoretical Physics. However, this hypothesis also only defers the solution of the question, and, supposing its scientific possibility, leads either to the remoter question, how life did originate in those other spheres, or to the metaphysical assertion of the eternity of life and of the eternal continuity of the living in the world, and shows therewith very clearly the impossibility of its explanation.

This inexplicability would still exist, if what is quite improbable should happen, namely, that the experimental attempts at artificially producing organic life should be successful, and if thus the question as to the generatio aequivoca, which during the past decades so much alarmed the minds of scientists and theologians, should be experimentally solved and answered in the affirmative. For in view of the hopes of a possible explanation of life, which is expected to be the reward for the success of {139} these attempts, Zoellner is fully right in saying: "That the scientists to-day set such an extremely high value on the inductive proof of the generatio aequivoca, is the most significant symptom of how little they have made themselves acquainted with the first principles of the theory of knowledge. For, suppose they should really succeed in observing the origin of organic germs under conditions entirely free from objection to any imaginable communication with the atmosphere, what could they answer to the assertion that the organic germs, in reference to their extension, are of the order of ether-atoms, and, with these, press through the intervals of the material molecules which form the sides of our apparatus?"

How little life is explained, at least according to the present state of our knowledge, also follows from the insufficiency of all attempts at defining it. The latest and most thorough attempt at such a definition of life, with which we are familiar, is that made by Herbert Spencer in his "First Principles", Sec. 25, and in his "Principles of Biology," Vol. I, Part I, Chap. 4 and 5. Having made thorough investigations, he arrives at the general formula: "Life is the continuous adjustment of internal relations to external relations." To this definition we will not make the objection that it is nothing but a logical abstraction from the common quality of all processes and phenomena of life; for it certainly lies in the nature of a definition that it can be nothing else but that. Nevertheless, we will state that such a definition of life not only does not lead us any nearer to the comprehension of its processes, and especially of the richness and the organization of its forms and functions, but that it {140} clearly shows us how little the origin of life is explained. For this very definition necessarily and obviously leads us to the questions: Whence do those internal relations originate, whence their adjustment to external relations, and whence the continuity of this adjustment? The answer to these questions this definition still owes us.

Therefore, not only self-consciousness and freedom, not only sensation and consciousness, but also life and the organic, remain a phenomenon which—at least, according to the present state of our knowledge and reasoning—enters into the realm of the world of phenomena as something new that can not be explained from the foregoing, although it presupposes the foregoing as the condition, not the cause, of its appearance; and no matter whether we have to think of the modality of its origin as a sudden or as a gradual one.

Sec. 4. The Elements of the World, the Theory of Atoms, and the Mechanical View of the World.

The investigating and thinking mind, when it attempts to explain the appearances and forms of that which exists, finds itself led further and further back, until it finally arrives at the last elements of the world and of matter. Whether we take the problem of life as solved or unsolved, the living has matter and its subordination to the efficiency of all its chemical and mechanical powers in common with the lifeless; and the organic, in its first beginnings, stands extraordinarily near to, and is grown on the ground of, the inorganic,—if not according to the category of cause and effect, still according to that of condition and consequence, of basis and structure. Therefore we stand at last before the {141} question of the final elements of matter, which, indeed, constitutes organic as well as inorganic bodies.

The answer to this question is attempted by the theory of atoms: the doctrine which teaches that the whole material world is composed of simple particles which are no farther divisible, and from whose juxtaposition the chemical elements—and, in respect to their other forms of existence and combination, the whole world of bodies, with all their forms, states, and changes,—are composed.

This theory has not only the practical value that the physical (and especially the chemical) sciences can make and use their formulas most easily under the supposition of such simple primitive elements; but it also has the great theoretical merit that it has broken down the old barriers between matter and force, and has thus promoted considerably our method of regarding the world of material substances. Toward this result, scientists and philosophers—and, among the latter, the thinkers and investigators of both views of the world, the theistic and the pantheistic, the ideal and the materialistic,—have worked with equal merit, and have equally enjoyed its fruits, with perhaps the single exception of so pure a materialist as Ludwig Buechner, who, it seems, does not like to give up his old doctrine of force and matter as the two inseparable, equivalent, and equally eternal elements of the universe. That matter itself, even when looked upon from a purely physical standpoint, has an incorporeal principle; that the whole world of bodies, as such, has but a phenomenal character; that not force and matter are the two empirico-physical principles of the world, but that matter itself must be a product of elementary {142} force active in the atoms; these doctrines have now be pretty nearly common property of natural science and philosophy. Investigators who like Wilhelm Wundt, rise from natural science to philosophy, or such as take their starting-point from philosophy—whether they be theists, like Lotze, I. H. Fichte, Ulrici, or occupy the ground of a pessimistic pantheism, as does Eduard von Hartmann,—all share this view and its fruits.

But in spite of all these preferences for the theory of atoms, we should not forget that it still has but hypothetical value—that it is but an idea of limits, which indicates, where the scientifically perceptible ceases, and that every attempt at moving this limit still farther on must either fail and lead into unsolvable contradictions, or, if successful, only leads to new difficulties and unsolved problems.

Already within that realm in which the theory of atoms is a supplemental hypothesis directly indispensable at present—i.e., within their application in physical sciences—we meet suppositions which raise great doubts and difficulties. Such a scientific difficulty occurs when the atomism of the natural philosophers supposes a double complexity of atoms, material atoms and atoms of ether: complexities which both penetrate one another, and are supposed to follow partly totally different, partly the same, elementary laws of force. Material atoms are subordinate to the law of gravitation, while atoms of ether are not; and yet both act legitimately upon one another,—as, for instance, when heat passes into motion and motion into heat, which certainly presupposes a law of power acting in common for both. Another difficulty lies in the atomism of the chemists; and still another {143} in the divergency of the aims at which the physical theory of atoms on the one hand and the chemical theory of atoms on the other seem to point. Chemistry is inclined to explain the difference of its numerous elements from the original difference of the atoms; and yet it is not at all certain that the elements of chemistry themselves are not composed of still more simple and less numerous primary elements. Many indications seem to point to such primary elements which are more simple in number and quality, and investigators even mention an element—hydrogen—in the direction of which we have to look for the way that will lead us to those primitive elements of matter. The divergency of aims, finally, consists in the fact that physical atomism prevailingly points to a conformity of the atoms of bodies; chemical atomism, on the contrary,—at least, according to its present state,—points to a dissimilarity among these.

The hypothetical and problematical nature of the theory of atoms strikes us still more clearly when we try to analyze it philosophically. First, we meet that antinomy which we always find where we try to pass beyond the limits of our empirical knowledge by means of conception. For, if the atoms still occupy space, we can not understand why they should not be further divisible, and if they do not occupy space, we can not understand how any sum of that which does not occupy space, can finally succeed in filling space. It is true, this very antinomy has led to the overcoming of that dualism of force and matter which so long enchained science, and the overcoming of which we greet as a progress of our theoretical knowledge of nature. We no {144} longer look upon the atoms as material elements, but as centres of force. The antinomy has the further merit that, in the realm of the knowledge of nature, it brings to our consciousness the great advantage of a concrete perception and reasoning over purely logical abstractions. For Ulrici, in his "God and Nature," is right in calling our attention to the fact that we must think about the atoms, not in an abstractly logical and an abstractly mathematical way, but concretely; that we have to consider them, not as mere quantities, but as qualities; and that we can then easily arrive at the perception of something which occupies space, and which therefore, according to abstract conclusions of logic and mathematics, could still be thought of as divisible in abstracto, but which, even as a consequence of its quality, of its concrete natural form, is no longer divisible in reality. Nevertheless, in spite of all these remarkable attempts at overcoming the difficulties of the theory of atoms, that antinomy returns as often as we undertake to make that clearly perceptible which we have at last gained a partial conception of; and thus shows us, from this side also, that even with the theory of atoms we have arrived at the limit where not only our observation, but also the preciseness and certainty of our conceptions, ceases.

By the atomic theory, we do not gain anything for the ultimate explanation of the world and its contents, not even if its present hypothetical value should be changed into a complete demonstration. For the whole theory but removes the question as to the origin of things from their sensible appearance to the elements of that appearance, and leaves us standing just as helpless before the elements as before the appearances. For {145} whence does the whole richness of the appearances in the world come? If the atoms are all alike, and their laws of force the simplest we can imagine, then their grouping into all the developments and formations of which we observe such an infinite and regularly arranged abundance, is not less unexplained than if we had not gone back to the theory of atoms at all. But if the atoms and their laws of force are different, the difficulty is not simplified, but doubled. For, first, the theory then owes us an answer to the questions wherein the difference of the atoms consists and whence it comes; and, second, the question we have to consider in supposing a uniformity of the atoms, is not disposed of or answered—the question, namely, as to the causes which bring these different atoms together to form precisely those complexities of atoms which we observe as the world of phenomena.

This insufficiency of the theory of atoms in explaining the world and its contents, is another proof to us that, however great the practical value of this theory may be for the operations of physics and chemistry, its theoretical value consists essentially in the fact that it formulates more accurately the perception of the limits of our exact knowledge. Even the idea of Lotze, that the atoms (in themselves different) are not really the final elements of matter, but consist of still more simple but likewise different elements, seems to us more a decoration than an extension of the limits at which our perception has arrived; we stand before a double door, but find both doors locked. We agree with DuBois-Reymond, when he declares, in his before-mentioned lecture, the impossibility of perceiving the last elements of the {146} world, matter and force, to be the other limit of our knowledge of nature which, together with the impossibility of the explanation of the origin of sensation and consciousness, remains forever fixed.

Likewise, the peculiar modification which G. Th. Fechner gives to the theory of the last elements of the world, cannot escape the charge of leaving the problem of the world scientifically just as unsolved as before. Fechner not only finds, as we have already mentioned, the difference between the organic and the inorganic in the difference of the mutual motions, but he also finds that the character of organic motions is exactly the same as that which the bodies of the universe have among themselves in their motions. Thus he distinguishes the cosmorganic motion, which is performed in the whole of the universe, and the molecular-organic motion, which we observe in the single organisms of the earth; he makes God the personal, self-conscious soul of this cosmical organism; and, in using the law of the tendency to stability, with which he completes the Darwinian selection theory, asserts that the organic in the whole of the universe, as well as in the narrow sphere of single bodies on the earth, is the first thing from which the inorganic was separated and became gradually fixed. Thus, in his opinion, the problem which up to the present has occupied investigators,—namely, how did the organic originate from the inorganic?—would have to be reversed to, how did the inorganic originate from the organic?

Preyer would also reach a similar result with his above-mentioned theory of the identity of life and motion. For according to this theory, the living would {147} be as old and common as motion, and the organic but the dregs of life.

We may, therefore, say that, without regard to the fact that neither pantheism nor theism will ever harmonize with Fechner's solution of this contrast which gives to God exactly the same position in the world as the soul has in the body, natural science will certainly treat with great reserve a cosmo-metaphysical system which so fully upsets all results of exact investigations into the history of origin and development, and has no other proof for itself than the identity, or at least the similarity, of the abstract formula according to which the molecular motions of organisms and the cosmical motions are performed. Although we thus have to deny to the proof of this identity or similarity the weight which Fechner gives to it, nevertheless it has still no small merit, since it throws new and clearer light upon the old thought, always attractive and yet so difficult to present,—of a macrocosmus and a microcosmus, which has been often enough treated with so much natural mysticism.

Thus, in our inquiry into the development of things, we have successively arrived at four points, each of which urged us to make the confession that here something new came into existence, which can not be explained from the preceding conditions of its being; these four points were: the origin of self-consciousness, the origin of sensation and consciousness, the origin of life, and finally the elements of the universe. Arrived at the last problem, we see the confession of our ignorance increased to the still more comprehensive confession that we are really not able fully to explain anything in the world. We are able to perceive a uniformity of law in the states and {148} changes of things, and to abstract therefrom common laws of nature; we can observe single objects, and perceive their states and changes in their connection with one another and in their dependence on those laws. But we are not able to explain scientifically either the origin of these laws or the last physical causes of the qualities of things, which follow these laws.

We should reach the same result if we had not started from the objective world of the existing, as we were induced to do by our subject, but from theoretical investigations. Here also we should immediately find ourselves in a world of relations between subject and object, of a regularly arranged abundance of subjective and objective qualities, states and processes, of which the objective only come to our knowledge through the medium of the subjective, and of regularly arranged laws to which both the subjective and the objective are commonly subordinate. But why just these and no other qualities of the subject and of objects exist, why just these and no other laws reign, why just this and no other relation takes place between the perceiving subject and the perceived object, would remain unanswered as before.

Amidst a generation which is so fond of reveling in the thought of an extension of all the limits of our knowledge, and is inclined to proclaim as true that which it wishes and hopes, investigators are not wholly wanting who very decidedly express their consciousness of these limits of our knowledge, and at the same time combine it with the most logical scientific reasoning and investigation. Even when in detail they reach these limits from the most varying points of view, and draw {149} them in different directions, they all agree in confirming the principle that it is one of the first and most indispensable conditions of successful investigation always to be conscious of the limits of its perception. Voices which remind mankind of these limits, are perhaps less popular, for man prefers to be reminded of the advances rather than of the limitations of his knowledge; but they are on that account the more worthy of our gratitude, for they keep us on the solid ground of the attainable from which alone sure progress in knowledge is possible. Among such philosophers we name Ulrici, and especially Lotze; among scientists, in the first place, two pioneers in their departments—namely, in the department of the mechanism of heat, Robert von Mayer—compare his "Bemerkungen ueber das mechanische Aequivalent der Waerme" ("Remarks on the Mechanical Equivalent of Heat"), and "Ueber nothwendige Consequenzen und Inconsequenzen der Waermemechanik" ("Necessary Consequences and Inconsequences of the Mechanism of Heat"), Stuttgart, Cotta;—and in the realm of the development of organisms, K. E. von Baer—compare his "Reden und kleinere Aufsaetze" ("Addresses and Essays"), 2 vols., St. Petersburg, 1864 and 1876. In this connection we have already mentioned the name of DuBois-Reymond. Otto Koestlin published two remarkable dissertations in this direction—"Ueber die Grenzen der Naturwissenschaft" ("Limits of Natural Science"), Tuebingen, Fues, 2d ed., 1874, and "Ueber natuerliche Entwicklung" ("Natural Development"), ib., 1875. In the latter he especially cautions against hastily confounding the laws of development of planets, development of the organic kingdom, and development {150} of the individual organisms. Recently, Wigand, in the second volume of his work already frequently mentioned, attempts, with an extreme energy which does too little justice to the representation and investigation of the still unsolved problems, to formulate the limits of the knowable.

A contrary extreme, and of its kind a still more one-sided corrective of this too great stability, we have in those investigators who, by reason of the great progress which has been made in the realm of the theoretical knowledge of nature, allow themselves to be drawn on to the hope of still explaining all states and processes in the world—the spiritual and the ethic processes as well as the physical—from the pure mechanism of atoms; and who see in that which thus far has been mechanically explained, the only and the infallible way of explaining all that is still obscure. They call this view the mechanical view of the world; and, as "monism," put it in opposition to the "vitalistic, teleological, and dualistic view of the world." In order to obtain a correct view of this standpoint, we quote from Haeckel's "Natural History of Creation", Vol. I, page 23, the following passage: "By the theory of descent we are for the first time enabled to conceive of the unity of nature in such a manner that a mechanico-causal explanation of even the most intricate organic phenomena, for example, the origin and structure of the organs of sense, is no more difficult (in a general way) than is the mechanical explanation of any physical process; as, for example, earthquakes, the courses of the wind, or the currents of the ocean. We thus arrive at the extremely important conviction that all natural bodies which are known to us are equally {151} animated, that the distinction which has been made between animate and inanimate bodies does not exist. When a stone is thrown into the air, and falls to earth according to definite laws, or when in a solution of salt a crystal is formed, the phenomenon is neither more nor less a mechanical manifestation of life than the growth and flowering of plants, than the propagation of animals or the activity of their senses, than the perception or the formation of thought in man." Here crystallization, organic life, sensation, and formation of thought, are expressly put in one line of mechanism with the falling of a stone.

In the following section we will have occasion to discuss this view as a view of the world; but we believe that the presentation of this idea, and the exclusive vindication of it as a complete view of the world, needs just here, where we still stand on the ground of the philosophy of natural perception, some critical sifting.

In the realm of material nature, mechanical explanation and general explanation is directly identical; i.e., a process of nature remains obscure so long and so far as its mechanism is not yet perceived, and in the same degree as its mechanism is perceived, the process also is explained. The uniformity of law in the occurrence of events according to the causal principle in the realm of material nature, can be approached by us in no other form than in that of mechanism, provided we understand by mechanism an activity according to law and which can be mathematically estimated as to size and number. So far, therefore, every scientific investigator in the knowledge of material nature takes his place on the standpoint of a mechanical view of the world. {152}

But here we have gone to the full extent to which we are justified in taking a mechanical view of the world, and have fixed its limits in its own proper realm—the realm of the scientific perception of the material world; even if we do not join with Wigand in resigning scientific inquiry in that direction, and express the expectation that these limits are not fixed and not to be designated in advance, but will be moved farther and farther, and that not only in regard to the knowledge of the quantity of phenomena (which even Wigand, as a scientific investigator, naturally admits), but also in regard to their quality. In our researches hitherto we have often met such limits. We have found that in the realm of the material world such important phenomena and processes as life are at present not yet fully explained. By the mechanical view of the world, we have been led back to the last elements and to the most elementary forces of matter, but have been convinced that we are no longer able to find them with scientific certainty, and that consequently not a single quality of material existence is really explained and traced back to its last material causes, to say nothing of the transcendental causes which are entirely inaccessible to our exact scientific knowledge.

Now there is another realm of existence, just as large as and, according to its value, still larger than, that of the material world, which, not on account of its scientific inaccessibility, but in conformity with its own peculiar nature, entirely withdraws itself from the mechanical view. It is the realm of psychical life; and, still more decidedly and more evidently, the realm of mind. As far as our observations go, the law of {153} causality reigns here also, and here also nothing takes place without a cause. But as here the realm in which the causal law reigns is no longer material nature, so even the form in which it is active is no longer that of mechanism. For we certainly cannot understand mechanical effect to be anything else than an effect of something material upon something material, whose uniformity of law can be exactly estimated mathematically as to size and number. Now if the application of mechanism to the psychical and spiritual realm does not express anything except the certainly quite insidious idea that here also causality reigns, it is nothing else but the substitution of another idea for the word mechanism—an idea which it never had in the entire use of language up to this time, and by the substitution of which the proof for a mechanism of the mind is not given, but surreptitiously obtained in a manner similar to the before-mentioned attempt of Preyer, surreptitiously to obtain the proof for the origin of life.

But if the mechanical explanation of the functions of the mind really means that they also consist in an effect of the material upon something material, and that this effect can be mathematically estimated as to size and number, it is an assertion which has first to be proven, but which cannot be proven and cannot be allowed even as an hypothesis, as a problem for investigation, because it contradicts our whole experience. And it contradicts not only the conclusions drawn from most natural appearances, which, as is well known, are deceitful and even tell us that the sun goes around the earth, but it contradicts the philosophical analysis just as much and even still more directly and decidedly than {154} the direct impression—as became clear to us at the lowest point of contact between the material and the psychical, viz., at sensation, when we showed the impossibility of scientifically explaining the origin of sensation.

It is easy to see what facts made it altogether possible to produce such a materialistic psychology and to give it at the first superficial view a certain appearance of truth; but it will not be difficult to detect its want of truth. According to our whole experience, the human mind is bound to the body; its proper activity, its whole communication with the material and immaterial world outside of it, even its whole mutual intercourse with the minds of fellow-beings, is performed by means of bodily functions which, as such, are subordinate to mechanism. Therefore "physiological psychology" certainly belongs to the most interesting of the branches of science which at present enjoy special care, and works in this realm, like those of Wundt, are worthy of the greatest attention. Now if these points of contact once exist between the material and the psychical and spiritual processes, so that material functions causally influence psychical and spiritual ones, and psychical and spiritual functions similarly influence material ones, there must also exist between the laws of material processes and those of psychical and spiritual functions a relation which makes possible such a mutual effect, and we must be able to abstract from it the existence of a common higher law of which on the one side the material laws, and on the other the psychical and spiritual, are but partial laws. Precisely here lie the indications which appear to favor materialism in psychology. But it is only an appearance. For, from the acknowledgment {155} and scientific investigation of a reciprocal action, to an identification of the two factors which act upon one another, is still an infinite step. If science is not even able to identify material motion and sensation, still less can it identify material motion and the spiritual and ethic activities. When this is done, it is done only in consequence of the same confounding of condition and cause which we had to expose on the occasion of the assertion of the possibility of explaining the origin of life or of sensation, and of consciousness or of self-consciousness. But we here also willingly admit that the realm in which causality reigns in the form of mechanism, aims at being the support, foundation, and instrument of another realm where causality still reigns, but mechanism ceases. How far investigation may still proceed in the direction of those interesting points and lines where both realms touch one another in causal reciprocal action, we do not know. We are hardly able to indicate the direction in which the investigation must proceed, and this direction seems to be assigned to it by the idea of Ausloesung.[8] The idea of Ausloesung, which plays such an {156} important role in physics, seems to be still fruitful for the knowledge of psycho-physical life: bodily functions loesen aus spiritual ones, spiritual functions bodily ones. But so much the more clearly does this theory show the limits of mechanism: mechanism reigns in the world of bodies from the Ausloesungen and to the Ausloesungen, with which the mind induces the body to activity, and the body the mind; beyond these limits causality still reigns, but no longer mechanism.

Now if thus the mechanical view of the world has within its own most proper realm—the realm of material phenomena—its limits, even if they are capable of being moved farther; and if it is without any scientific acceptance in the realm of soul and mind: its usurpations reach the highest possible degree when it pretends to {157} explain the last causes of things. For from its very nature it follows that it is only able to explain the reciprocal action of material things among themselves, when these things in their finalities, or the causes of their qualities and conditions, are already present, and the laws which they follow are already active. As to the origin of those qualities or their causes, and of these laws, this view leaves us entirely in the dark.

* * * * * {158}

CHAPTER II.

METAPHYSICAL CONCLUSIONS DRAWN FROM THE DARWINIAN THEORIES.

Sec. 1. Elimination of the Idea of Design in the World.—Monism.

From this mechanical view of the world, quite a peculiar conclusion has been recently drawn—not by Darwin, who does not give any opinion at all about the mechanical view of the world, as such, or about its extension and influence, nor, indeed, by Darwinians, not even by all followers of a mechanical view of the world, but only by a part of them; namely, by those who have in a high degree attracted to themselves the attention of reading people. This conclusion is nothing less than the elimination of the idea of design in nature. This phenomenon demands our attention. Heretofore, the proof of plan, design, and end in nature, at large and in detail, was looked upon as the most beautiful blossom and fruit of a thoughtful contemplation of nature; it was the great and beautiful common property, in the enjoyment of which the direct, the scientific, and the religious contemplation of nature peacefully participated. Now this view is to be given up forever, in consequence of nothing else than Darwin's selection theory. With an energy—we may say with a passionateness and confidence of victory—such as we were accustomed to see only in the most advanced advocates of materialism, Ludwig {159} Buechner, D. F. Strauss, Haeckel, Oskar Schmidt, Helmholtz, the editor of the "Ausland" and some of his associates, and our often-mentioned "Anonymus,"—in a common attack, assail every idea of a conformity to an end in nature, every idea of a goal toward which the development at large and individually strives; in a word, the whole category of teleology.[9]

In order to be just in our judgment, we shall have to let the advocates of this view speak for themselves;—the advocates of Dysteleology, as Haeckel, who is so extremely productive in forming new exotic words, calls it; or of Aposkopiology, as Ebrard, in his "Apologetik" ("Apologetics"), correcting the etymology, {160} somewhat pedantically calls it; or of Teleophoby, as it is called by K. E. von Baer, in humorous irony.

The anonymous author of the book called "The Unconscious from the Standpoint of Physiology and Descent Theory", asserts that, while the descent theory but puts the teleological principle in question by withdrawing the ground for a positive proof—an assertion which we certainly have to reject most decidedly (compare Part II, Book II, Chap. I, Sec. 2-Sec. 6)—the selection theory directly rejects it. Natural selection, he says, solves the seemingly unsolvable problem of explaining the conformity to the end in view, as result, without taking it as an aiding principle. And Helmholtz says: "Darwin's theory shows how conformity to the end in the formation of organisms can also originate without any intermingling of an intelligence by the blind administration of a law of nature."

Haeckel really revels in these ideas. He says (Nat. Hist. of Creat., Vol. I, p. 19): "These optimistic views [of the much-talked-of purposiveness of nature or of the much-talked-of beneficence of the Creator] have, unfortunately, as little real foundation as the favorite phrase, 'the moral order of the universe,' which is illustrated in an ironical way by the history of all nations.... If we contemplate the common life and the mutual relations between plants and animals (man included), we shall find everywhere, and at all times, the very opposite of that kindly and peaceful social life which the goodness of the Creator ought to have prepared for his creatures—we shall rather find everywhere a pitiless, most embittered Struggle of All against All. Nowhere in nature, no matter where we turn our eyes, does that {161} idyllic peace, celebrated by the poets, exist; we find everywhere a struggle and a striving to annihilate neighbors and competitors. Passion and selfishness—conscious or unconscious—is everywhere the motive force of life.... Man in this respect certainly forms no exception to the rest of the animal world." And on page 33: "In the usual dualistic or teleological (vital) conception of the universe, organic nature is regarded as the purposely executed production of a Creator working according to a definite plan. Its adherents see in every individual species of animal and plant an 'embodied creative thought,' the material expression of a definite first cause (causa finalis), acting for a set purpose. They must necessarily assume supernatural (not mechanical) processes of the origin of organisms.... On the other hand, the theory of development carried out by Darwin, must, if carried out logically, lead to the monistic or mechanical (causal) conception of the universe. In opposition to the dualistic or teleological conception of nature, our theory considers organic as well as inorganic bodies to be the necessary products of natural forces. It does not see in every individual species of animal and plant the embodied thought of a personal Creator, but the expression for the time being of a mechanical process of development of matter, the expression of a necessarily active cause, that is, of a mechanical cause (causa efficiens). Where teleological Dualism seeks the arbitrary thoughts of a capricious Creator in miracles of creation, causal Monism finds in the process of development the necessary effects of eternal immutable laws of nature." Haeckel's "Anthropogeny" also is replete with attacks upon a teleological {162} view of nature, which leave nothing wanting in distinctness and coarseness. On page 111, Vol. I, we read: "The rudimentary organs clearly prove that the mechanical, or monistic conception of the nature of organisms is alone correct, and that the prevailing teleological, or dualistic method of accounting for them is entirely false. The very ancient fable of the all-wise plan according to which 'the Creator's hand has ordained all things with wisdom and understanding,' the empty phrase about the purposive 'plan of structure' of organisms is in this way completely disproved. Stronger arguments can hardly be furnished against the customary teleology, or Doctrine of Design, than the fact that all more highly developed organisms possess such rudimentary organs." (Compare also Vol. II, p. 439: "The rudimentary organs are among the most overwhelming proofs against the prevailing teleological ideas of creation.") According to his opinion (Vol. I. p. 245), comparative anatomy may no longer look for a "pre-arranged plan of construction by the Creator." Besides, he calls it an anthropocentric error to look upon man as a preconceived aim of creation and a true final purpose of terrestrial life; and on page 17, of Vol. II, he supports this judgment by comparing the relative shortness of the existence of mankind with the length of the preceding geological periods: "Since the awakening of the human consciousness, human vanity and human arrogance have delighted in regarding Man as the real main-purpose and end of all earthly life, and as the centre of terrestrial Nature, for whose use and service all the activities of the rest of creation were from the first defined or predestined by a 'wise providence.' How utterly baseless these {163} presumptuous anthropocentric conceptions are, nothing could evince more strikingly than a comparison of the duration of the Anthropozoic or Quaternary Epoch with that of the preceding Epochs." And on page 234, Vol. II: "Hence it is that, in accordance with the received teleological view, it has been customary to admire the so-called 'wisdom of the Creator' and the 'purposive contrivances of His Creation' especially in this matter. But on more mature consideration it will be observed that the Creator, according to this conception, does after all but play the part of an ingenious mechanic or of a skillful watchmaker; just, indeed, as all these cherished teleological conceptions of the Creator and His Creation are based on childish anthropomorphism.... But it is exactly on this point that the history of evolution proves most clearly that this received conception is radically false. The history of evolution convinces us that the highly purposive and admirably constituted sense organs, like all other organs, have developed without premeditated aim."