We account for it by the supposition that his metaphysical views, carefully excluded from his scientific work, are the results of an earlier and less severe training than that which has secured to us his valuable positive contributions to the theory of Natural Selection.   Mr. Wallace himself is fully aware of this contrast, and anticipates a scornful rejection of his theory by many who in other respects agree with him. The doctrines of the special and prophetic providences and decrees of God, and of the metaphysical isolation of human nature, are based, after all, on barbaric conceptions of dignity, which are restricted in their application by every step forward in the progress of science.  And the sense of security they give us of the most sacred things is more than replaced by the ever-growing sense of the universality of inviolable laws, -- laws that underlie our sentiments and desires, as well as all that these can rationally regard in the outer world.  It is unfortunate that the prepossessions of religious sentiment in favor of metaphysical theories should make the progress of science always seem like an indignity to religion, or a detraction from what is held as most sacred; yet the responsibility for this belongs neither to the progress of science nor to true religious sentiment, but to a false conservatism, an irrational respect for the ideas and motives of a philosophy which finds it more and more difficult with every advance of knowledge to reconcile its assumptions with facts of observation.

Thus, in the abstract theory of the pendulum, the phenomena of force involved are limited simply to the vertical rise and fall of the weight, upon which alone the amounts of its motions depend.   The times of its vibrations are determined by the regulating length of the rod, which in theory adds nothing to, and subtracts nothing from, the efficient mutually convertible forces of motion and gravity.  What is here assumed in theory to be true, we assume to be actually and absolutely true of mental agencies.

which seems to us erroneous, that all causation is reducible to the conversions of equivalent physical energies.  It may be trite (at least we are not prepared to dispute the assumption) that every case of real causation involves such conversions or [p. 122] changes in forms of energy, or that every effect involves changes of position and motion.  Nevertheless, every case of real causation may still involve also another mode of causation. A much simpler conception than our author's theory, and one that seems to us far more probable is that the phenomena of conscious volition involve in themselves no proper efficiencies or forces coming under the law of the conservation of force, but are rather natural types of causes, purely and absolutely regulative, which add nothing to, and subtract nothing from, the quantities of natural forces.   No doubt there is in the actions of the nervous system a much closer resemblance than this to a machine.  No doubt it is automatically regulated, as well as moved, by physical forces; but this is probably just in proportion as its agency -- as in our habits and instincts -- is removed from our conscious control. 

But we do not see why Mr. Wallace is not driven by it to the dilemma of assuming free-wills for all sentient organisms; or else of assuming, with Descartes, that all but men are machines.

We may not be able to understand how such regulation is possible; how sensations and other mental conditions can restrain, excite, and combine the conversions of physical forces in the cycles into which they themselves do not enter; though there is a type of such regulation in the principles of theoretical mechanics, in the actions of forces which do not affect the quantities of the actual or potential energies of a system of moving bodies, but simply the form of the movement, as in the rod of the simple pendulum.  Such regulation in the sensitive organism is more likely to be an ultimate inexplicable fact; but it is clear that even in a machine the amounts of the regulating forces bear no definite relations to the powers they control, and might, so far as these are directly concerned, be reduced to nothing as forces; and in many cases they are reduced to a minimum of the force of friction.  They must,[p. 121 however, be something in amount in a machine, because they are physical, and, like all physical forces, must be derived in quantity from pre-existing forms of force.  To infer from this that the Will must add something to the forces of the organism is, therefore, to assume for it a material  nature. But  Mr. Wallace escapes, or appears to think (as others think who hold this view) that he escapes, from complete materialism by the doctrine of the freedom of the Will.  Though he makes the Will an efficient physical force, he does not allow it to be a physical effect.  In other words, he regards the Will as an absolute source of physical energy, continually adding, though in small amounts, to the store of the forces of nature; a sort of molecular leakage of energy from an absolute source into the nervous system of animals, or, at least, of men.

"However delicately a machine may be constructed, with the most exquisitely[p. 120] contrived detents to release a weight or spring by the exertion of the smallest possible amount of force, some external force will always be required; so in the animal machine, however minute may be the changes required in the cells or fibres of the brain, to set in motion the nerve currents that loosen or excite the pent-up forces of certain muscles, some force must be required. to effect those changes."

We say, and say truly, that a stone has no sensation, since it exhibits none of the signs that indicate the existence of sensations.   It is not only a purely objective existence, like everything else in nature, except our own individual self-consciousness, but its properties indicate to us no other than this purely objective existence, unless it be the existence of God.  To suppose that its properties could possibly result in a sensitive nature, not previously existing or co-existing with them, is to reason entirely beyond the guidance and analogies of experience. It is a purely gratuitous supposition, not only metaphysical or transcendental, but also materialistic; that is, it is not only asking a foolish question,[p. 119] but giving a still more foolish answer to it.  In short, the metaphysical problem may be reduced to an attempt to break down the most fundamental antithesis of all experience, by demanding to know of its terms which of them is the other. To this sort of fatuity belongs, we think, the mystical doctrine which Mr. Wallace is inclined to adopt, "that FORCE is a product of MIND"; which means, so far as it is intelligible, that forces, or the physical antecedents and conditions of motion (apprehended, it is true, along with motion itself through our sensations and volitions), yet bear to our mental natures the still closer relation of resemblance to the prime agency of the Will; or it means that "all force is probably will-force." Not only does this assumed mystical resemblance, expressed by the word "will-force," contradict the fundamental antithesis of subject and object phenomena (as the word "mind-matter" would), but it fails to receive any confirmation from the law of the correlation of the physical forces.

The " origin of consciousness," or of sensation and thought, is relegated similarly by Mr. Wallace to the immediate agency or interposition of a metaphysical cause, as being beyond the province of secondary causes, which could act to produce it under the principle of Natural Selection.  And it is doubtless true, nay, unquestionable, that sensation as a simple nature, with the most elementary laws of its activity, does really belong to the primordial facts in that constitution of nature, which is presupposed by the principle of utility as the ground or condition of the fitnesses through which the principle acts.  In like manner the elements of organization, or the capacities of living matter in general, must be posited as antecedent to the mode of action which has produced in it, and through its elementary laws, such marvelous results.  But if we mean by "consciousness" what the word is often and more properly used to express,-that total and complex structure of sensibilities, thoughts, and emotions in an animal mind, which is so closely related to the animal's complex physical organization, -- so far is this from  being beyond the province of Natural Selection, that it affords one of the most promising fields for its future investigations.[4]  Whatever the results of such investigations, [p. 116] we may rest assured that they will not solve; will never even propound the problem peculiar to metaphysics (if it can properly [p. 117] be called a problem), the origin of sensation or simple consciousness, the problem par excellence of pedantic garrulity or philosophical childishness. 

The existence of feelings of approval and disapproval, or of likings and aversions to certain classes of actions, and a sense of obligation, are eminently useful in the government of human society, even among savages. These feelings may be associated with the really useful and the really harmful classes of actions, or they may not be.  Such associations are not determined simply by utility, any oftener than beliefs are by proper evidence.  But utility tends to produce the proper associations; and in this, along with the increase of these feelings themselves, consists the moral progress of the race.  Why should not a fine sense of honor and an uncompromising veracity be found, then, among savage tribes, as in certain instances cited by Mr. Wallace; since moral feelings, or the motives to the observance of rules of conduct, lie at the foundation of even the simplest human society, and rest directly on the utility of man's political nature; and since veracity and honor are not merely useful, but indispensable in many relations, even in savage lives?   Besides, veracity being one of the earliest developed instincts of childhood, can hardly with propriety be regarded as an original moral instinct, since it matures much earlier than the sense of obligation, or any feeling of the sanctity of truth.  It belongs rather to that social and intellectual part of human nature from which language itself arises.  The desire of communication, and the desire of communicating the truth, are originally identical in the ingenuous social nature.  Is not this the source of the "mystical sense of wrong," attached to untruthfulness, which is, after all, regarded by mankind at large as so venial a fault ?  It needs but little early moral discipline to convert into a strong moral sentiment so natural an instinct.  Deceitfulness is rather the acquired quality, so far as utility acts directly on the development of the individual, and for his advantage; but the native instinct of veracity is founded on the more primitive utilities of society and human intercourse. 

Natural Selection cannot, it is true, be credited with such relations in development.  But neither can they be attributed to a special providence in any intelligible sense.  They belong rather to that constitution of nature, or general providence, which Natural Selection presupposes.

The fact that it does not require Natural Selection, but only the education of the individual savage, to develop in him these results, is to us a proof, not that the savage is specially provided with faculties beyond his seeds

If they imply faculties which are useless to the savage, we have still the natural alternative left us, which Mr. Wallace does not consider, that savages, or all the races of [p. 112] savages now living, are degenerate men, and not the proper representatives of the philosopher's ancestors.  But this alternative, though the natural one, does not appear to us as necessary; for we are not convinced that "the power of conceiving eternity and infinity, and all those purely abstract notions of form, number, and harmony, which play so large a part in the life of civilized races," are really so "entirely outside of the world of thought of the savage" as our author thinks. 

the powers of imagination in animals, we should have a fundamentally new order of mental actions; which, with the requisite motives to them, such as the social nature of man would afford, might go far towards defining the relations, both mental and physical, of human races to the higher brute animals.  Among these the most sagacious and social, though they may understand language, or follow its significations, and  even by indirection acquire some of its uses, yet have no direct power of using, and no power of inventing it.[p. 111]

In his obvious anxiety to establish for the worth of human nature the additional dignity of metaphysical isolation, Mr. Wallace maintains the extraordinary thesis that "the brain of [p. 109] the savage is larger than he needs it to be"; from which he would conclude that there is in the size of the savage's brain a special anticipation or prophecy of the civilized man, or even of the philosopher, though the inference would be far more natural, and entirely consistent with Natural Selection, that the savage has degenerated from a more advanced condition.  The proofs of our author's position consist in showing that there is a very slight difference between the average size of the savage's brain and that of the European, and that even in prehistoric man the capacity of the skull approaches very near to that of the modern man, as compared to the largest capacity of anthropoid skulls.  Again, the size of the brain is a measure of intellectual power, as proved by the small size of idiotic brains, and the more than average size of the brains of great men, or "those who combine acute perception with great reflective powers, strong passions, and general energy of character."  By these considerations "the idea is suggested of a surplusage of power, of an instrument beyond the needs of its possessor."

Man is distinguished from all soft and delicate skinned terrestrial mammals in having no hairy covering to protect his body.  In other mammals the hair is a protection against rain, as is proved by the manner in which it is disposed, -- a kind of argument, by the way, especially prized by Cuvier, which has acquired great validity since Harvey's reasonings on the valves of the veins.[2]  The backs of these animals are more especially protected in this way, But it is front the back more especially that the hairy covering is missed in the whole human race; and it is so effectually abolished as a character of the species, that it never occurs even by such reversions to ancestral types as are often exhibited in animal races.  How could this covering have ever been [p. 106] injurious, or other than useful to men?  Or, if at any time in the past history of the race it was for any unknown reason injurious; why should not the race, or at least some part of it, have recovered from the loss and acquired anew so important a protection ?  Mr. Wallace is not unmindful of Mr. Darwin's doctrine of Correlated Variation, and the explanation it affords of useless and even injurious characters in animals; but he limits his consideration of it to the supposition that the loss of hair by the race might have been a physiological consequence of correlation with some past unknown hurtful qualities.  From such a loss, however, he argues, the race ought to have recovered.  But he omits to consider the possible correlation of the absence of hair with qualities not necessarily injurious, but useful, which remain and equally distinguish the race.   Many correlated variations are quite inexplicable.  "Some are quite whimsical: thus cats, which are entirely white and have blue eyes, are generally deaf," and very few instances could be anticipated from known physiological laws, such as homological relations.  There is, however, a case in point, cited by Mr. Darwin, the correlation of imperfect teeth with the nakedness of the hairless Turkish dog.  If the intermediate varieties between men and the man-apes had been preserved, and a regular connection between the sizes of their brains, or developments of the nervous system, and the amount of hair on their backs were observed, this would be as good evidence of correlation between these two characters as that which exists in most cases of correlation. But how in the absence of any evidence to test this or any other hypothesis, can Mr. Wallace presume to say that the law of Natural Selection cannot explain such a peculiarity?  It may be that no valid proof is possible of ally such explanation, but how is he warranted in assuming on that account some exceptional and wholly occult cause for it?  There is a kind of correlation between the presence of brains and the absence of hair which is not of so obscure a nature, and may serve to explain in part, at least, why Natural Selection has not restored tile protection of a hairy coat, however it may have been lost.  Mr. Wallace himself [p. 107] signalizes this correlation in the preceding essay.  It is that through which art supplies to man in a thousand ways the deficiencies of nature, and supersedes the action of Natural Selection.   Every savage protects his back by artificial coverings. Mr. Wallace cites this fact as a proof that the loss of hair is a defect which Natural Selection ought to remedy

We may generalize from this and from Mr. Darwin's observation on the comparatively extreme variability of plants, that in the scale of life there Is a gradual decline in physical variability, as the organism has gathered into itself resources for meeting the exigencies of changing external conditions; and that while in the mindless and motionless plant these resources are at a minimum, their maximum is reached in the mind of man,

Does not a like foreseeing power, ordaining and governing the whole of nature, anticipate and specially provide for some of its adaptations?  This appears to be the distinctive position in which Natural Theology now stands.

doctrine of Final Causes is deprived of the feature most obnoxious to its opponents, that abuse of the doctrine "which makes the cause to be engendered by the effect." But it is still competent to the devout mind to take a broader view of the organic world, to regard, not its single phases only, but the whole system from its first beginnings as presupposing all that it exhibits, or has exhibited, or could exhibit, of the contrivances and adaptations which may thus in one sense be said to be foreordained.  In this view, however, the organical sciences lose their traditional and peculiar value to the arguments of Natural Theology, and become only a part of the universal order of nature, like the physical sciences generally, in the principles of which philosophers have professed to find no sign of a divinity.  But may they not, while professing to exclude the idea of God from their systems, have really included him unwittingly, as immanent in the very thought that denies, in the very systems that ignore him?

bound together by the bond of what must still be regarded as an hypothesis, -- an hypothesis, however, which has no rival with any student of nature in whose mind reverence does not, in some measure, neutralize the aversion of the intellect to what is arbitrary.

Mr. Wallace and Mr. Darwin arrived at the same convictions in regard to the derivation of species, in entire independence of each other,

and it seems likely that we shall witness the unparalleled spectacle of an all but universal reception by the scientific world of a revolutionary doctrine in the lifetime of its author