SCIENTIFIC faith is no more smooth sailing than is theological faith. One involves about as many mysteries, as many unthinkable truths, as the other. It is unthinkable that a particle of matter can be so small that it cannot be made smaller, yet the atomic theory of matter involves this contradiction. The luminiferous ether, the most dense and at the same time the most attenuated body in the universe, which science has invented to account for the action of bodies upon other bodies at a distance, is unthinkable; but with all the contradictions which it involves, we are compelled to assume its reality in order to account for things as we know them.

How many things may be affirmed of the visible, ponderable bodies on the earth's surface which are just the opposite of what is true of the invisible, imponderable bodies of the interior world of matter, and which also do not hold among the bodies of celestial space! Thus all inanimate bodies on the earth's surface are at rest until some force exterior to themselves acts upon them. In the world of molecular physics the molecules and atoms and electrons are self-moved, and are in perpetual motion. If the Brunonian movement extended to visible ponderable bodies, the earth would be uninhabitable; we should behold a sight such as we have never yet beheld. Spontaneous motion never takes place among inanimate bodies, while it is the rule among the atoms of which they are composed. Gravity and friction bind the bodies on the surface of the earth, but these laws are inoperative in the world of atoms and electrons. On the other hand, when we reach the astronomic world, or the sidereal universe, we find the same condition that prevails in the world of the infinitely little: perpetual motion goes on, friction is abolished, and nothing is at rest; there are collisions and disruptions just as there are in the world of atoms. Height and depth, upper and under, east and west, north and south, weight and inertia, as we experience them, have vanished. There are no boundaries, no ending and no beginning, no centre and no circumference; the infinite cannot have any of these. Rest and motion are relative terms. The sun is at rest with reference to the earth, but in motion with reference to some larger system, which is again at rest when tried by the sun. Motion implies something which is not in motion. The bodies we know have weight with reference to the earth, as the earth has with reference to some larger body, and this again with reference to some other still larger, and so on; but the universe as a whole can have no weight. A body at the centre of the earth can have no weight. If unsupported, would it move up or down? The infinitely little and infinitely vast alike baffle the understanding, developed as it is by our concrete finite life. Creation is typified by the sphere. A circle is a straight line that at every point ceases to be a straight line, and the earth's surface is a plane that every moment ceases to be a plane. Following the surface of the earth does not carry us to the under side, because there is no more an under side than there is an upper side – there is only a boundless surface. But if it were possible for us to build a globe upon the earth of any conceivable dimensions would it not have an upper and an under side?

The mysteries of religion are of a different order from those of science; they are parts of an arbitrary system of man's own creation; they contradict our reason and our experience, while the mysteries of science are revealed by our reason, and transcend our experience. One implies the supernatural, while the other implies inscrutable processes or forces in the natural. That man is of animal origin is a deduction of reason, but the fact so far transcends our experience that it puts a great strain upon our scientific faith.

The miracles of our theology do violence to our understanding, but it is a part of our faith to accept them. The miracle of the loaves and the fishes, and of the turning of water into wine, have their parallels in chemical reactions, as in the conversion of starch into sugar, or of sugar into an acid; the mystery is that of chemical transformations, and occurs in the everyday processes of nature, while the biblical miracles are exceptional occurrences, and are never repeated.

The miracles of religion are to be discredited, not because we cannot conceive of them, but because they run counter to all the rest of our knowledge; while the mysteries of science, such as chemical affinity, the conservation of energy, the indivisibility of the atom, the change of the non-living into the living, and the like, extend the boundaries of our knowledge, though the modus operandi of these changes remains hidden.

We do not know how the food we eat is transformed into the thoughts we think; in other words, the connection of the physical with the mental baffles us; but our familiarity with the phenomena causes us to look upon them as a matter of course. In fact, while most of the mysteries and marvels of the prescientific ages only served to measure the depth of the mental darkness of those ages, the mysteries and the marvels of modern science serve to measure the depths to which we have penetrated into the hidden processes of natural law.

The scientific faith which triumphs over all obstacles is not common. The late Alfred Russel Wallace was an eminent scientist and naturalist, co-laborer with Darwin in sustaining the theory of the origin of species by natural selection; but he could not accept the whole of Darwinism. The break in his scientific faith is seen in his failure to accept completely the animal origin of man; he looked upon man's spiritual nature as a miraculous addition to his animal inheritance. Natural science owes a great debt to Agassiz, but he, too, faltered before the problem of the origin of species through natural descent. He belonged to an age that had not fully emancipated itself from the dogmas of the church. He saw an incarnated thought of the Creator in every species of animal and plant. The great majority of mankind still see a dualist world – half natural and half supernatural. But the strict scientist knows only the natural. Even the origin of life is to him only a problem of the inherent potency of matter.

Darwin's scientific faith was not quite able to stand alone; it had to lean upon teleological props. He could not accept the whole proposition of the natural origin of man and of other forms of life; his theory of descent had to start with a few forms, animal and vegetable, three or four, miraculously brought into the world by the creative power of an omnipotent being; these few original forms, through the action of natural selection, working upon chance variation, gave rise to all the infinite diversity of forms that now people the earth. Darwin's scientific faith was strong where that of Wallace was weak, inasmuch as he had no more difficulty in accounting for the mind of man by the theory of descent, than he had in accounting for the body of man. Both were an evolution of lower forms. His was a type of mind much more steady and consistent than was the mind of Wallace. Darwin's mind was of the planetary order, while Wallace's was more cometary. The later works of Wallace are a curious mixture of scientific data and theological moonshine.

Darwin's conviction of the origin of species through descent was so deep and whole-hearted that one wonders why it did not carry him back into the problem of the very beginning of life upon the globe. If natural law is adequate to account for the wonderful diversity of vegetable and animal forms, including the body and the soul of man, why should it not be adequate to account for the origin of the first primordial forms? If we are to believe that the mentality and spirituality of man as we know him to-day could arise from the blind, unreasoning lower orders, should we have any trouble in believing that living matter could arise or be evolved from the nonliving? The change is no greater in the latter case than in the former.

Are we to look upon the universe as half natural and half supernatural? Must it not be entirely one or the other to be a universe? Is it any easier to believe that God planted the germs of evolution in a few forms, created out of hand, so to speak, than it is to believe that He kindled the evolutionary impulse in matter itself? If we believe that one species was brought into being by a special act of creative energy, are we not bound to believe that all species were? It is the old story of our fathers: that the Creator is active in nature at certain times and places, and is passive at others. The processes of creation being miraculously started, they then continue under the guidance of natural law.

This break in Darwin's scientific faith does not at all detract from the immense value of his work. I only point to it as showing how difficult it was for even his mind to commit itself unreservedly to the full guidance of natural science. Tyndall, whose scientific faith was more consistent, saw the "promise and the potency" of all terrestrial life in matter itself, but he wrote matter with a big M, and declared that at bottom it was essentially mysterious and transcendental; and Bruno, in declaring that matter was the mother of us all, brought the Creator near us in the same way. Such views simply show the creative energy as always immanent in the universe. They free our minds of the notion that creation is a miracle at one end, and ordinary development at the other; that a primary cause sets the machine going, then turns it over to secondary causes. How is it possible to conceive of so-called secondary causes, except as phases of the First Cause? When we use the phrase, the idea of delegated power, drawn from our civic experience, seems to be in our minds. But I doubt if the universe is run on this plan, though our ecclesiasticism has made much of this idea. Our idea of cause, anyhow, is drawn entirely from our experience with material bodies and forces. In living nature, and in the brain of man, cause and effect meet and become one. There is no up and no down, no east and no west, no north and no south, in the depths of sidereal space; neither do any other of our mundane notions of primary and secondary causes apply to the universe as a whole.

The rain causes the grass to grow, and the sun causes the snow to melt, but we cannot apply the idea of cause, in this sense, to nature as a whole, but only to parts of nature. Gravitation caused Newton's apple to fall, but what causes the earth to fall forever and ever, and never to fall upon the body that is said to attract it?

Huxley's scientific faith was more radical and uncompromising than Darwin's. It never went into partnership with the old teleological notions of creation. Huxley not only accepted the development theory, with all that it implies, but, so far as I can make out, he accepted the theory of the physicochemical origin of life itself. He found no more place for miracle at the beginning than at the end of evolution, yet he repudiated materialism as emphatically as he rejected what he calls spiritualism, – declaring that the latter was only the former turned bottom-side up. While recognizing that "the logical methods of physical science are of universal applicability," he saw clearly enough that many subjects of thought and emotion – doubtless he would say, many forms of truth – lie entirely outside the province of physical science. He recognized three forms of reality in the universe, – matter, energy, and consciousness, – and that the last-named was no conceivable modification of either of the others. Whether he assigned to consciousness the same cosmic rank as to matter and energy, does not appear. It is quite certain that matter and energy existed before consciousness appeared, and will continue to exist after it disappears. But, in making this statement, are we projecting our consciousness into the past, and into the future?

I note one weakness in Huxley's faith: it seems to have balked at accepting the reality of things it could not conceive of. While looking upon the theory of the atomic constitution of matter as a valuable working hypothesis, it balked at the objective existence of the atom, – a point of matter which occupied space and had form and weight, and yet was indivisible. This was beyond his power of conception, as it is beyond the power of conception of the best of us. Yet we have to accept the atom on the demonstrations of experimental science. The helium atom has been proved to be an objective entity as truly as is the sun in heaven. The apparent contradiction of an indivisible body is involved in our habits of thought formed by our dealings with ponderable bodies; we are introduced to the world of chemical reactions. We cannot conceive or picture to ourselves just what takes place when two gases unite chemically, as when hydrogen and oxygen unite to form water. Our only resource is to apply to the process mechanical images; our experience affords us no other.

We fancy that the difference between two compounds with the same chemical formula, but with widely different properties, – say alcohol and ether, – consists in the different arrangement of the particles. Arranged in one order, they produce one compound; arranged in a different order, they result in a compound with different properties. Yet every particle of these gases is supposed to be exactly like every other particle. How hard, then, to conceive of any mere spatial arrangement of them as resulting in such widely different products. One has to think of each atom or electron as a little world in itself, containing different stores of energy or vibrating at a different rate of speed, in order to see substances of such different properties arising out of the different orders in which the atoms are arranged in the molecule, and the molecules in the mass. If the atoms of carbon or oxygen or hydrogen are each as unique and individual as men and women are, one can see that the order in which they join hands or select their partners may be fraught with important consequences. Or if the atoms are vibrating each with a different degree of energy, or carry different charges of electricity, then one can see that the different orders in which they stand to each other would be significant. But no mechanical image, nor the action and interaction of ponderable bodies in time and space, afford us a key to chemical combination.

How can we figure to ourselves any sort of spatial disposition of the ultimate particles of the invisible gases of oxygen and hydrogen that shall result in a product so unlike either as water? How impossible it all is in the light of our experience with visible bodies! Each atom or electron seems to get inside the other. But how can an indivisible particle of matter have either an inside or an outside, or place, or weight, or any other property that we ascribe to the bodies that we see and feel? What a world of the imagination it all is! It introduces us to some of the unthinkable truths of science – truths beyond our power to grasp, yet which experimental science verifies. It is unthinkable that matter and motion can exist without friction; that two bodies can occupy the same space at the same time; that a particle can be so small that it might not be smaller, or so large that it might not be larger; that space is without limits, creation without beginning; that at the centre of the earth there is no up and no down, on its surface no under and no over. Two waves of sound may interfere with each other and produce a silence, and two waves of light produce a darkness,

Molecular physics has made great strides since Huxley's time. With all the phenomena of electricity before him, he could not conceive of electricity as a positive entity; he seems to have regarded it as only a mode of motion, like heat. How shall we think of dematerialized substance, of disembodied energy, of a fluid as elusive and ubiquitous as thought itself, or of the transformation of one form of energy into another, as of electrical energy into mechanical? Electricity disappears in matter beyond the reach of any analysis to reveal; it is summoned again from matter as by the wave of a wand. In a thunderstorm we see it rend the heavens and disappear again into its impossible lair as quick as thought – energy which is not energy. Yet we know the reality of all these things, and the atomic theory of electricity is securely established. This gross matter with which life struggles, and which we conceive of as at enmity with spirit, is far more wonderful stuff than we have ever dreamed of, and the step from the clod to the brain of man is not so impossible as it seems. There is deep beneath deep all around us. Gross matter has its interior in the molecule; the molecule has its interior in the atom; the atom has its interior in the electron; and the electron is matter in its fourth or its ethereal estate. We easily conceive of matter in the three states, – the solid, the liquid, the gaseous, – because experience is our guide; but how are we to figure to ourselves matter in the ethereal estate? In other words, how are we to grasp the electric constitution of matter?

In Sir Oliver Lodge we have an example of a thoroughly trained and equipped scientific mind which yet, to account for things as we find them in this world, has to postulate another world of a different order – the world of spiritual reality – interpenetrating and interacting with the visible and tangible world about us. In doing this, Sir Oliver takes an extra-scientific step and lays himself open to the same criticism that has been visited upon Alfred Russel Wallace.

Our Professor Loeb would account for all our gods through physical and chemical changes in matter, and would probably look as much askance upon Huxley's "consciousness" as belonging to the trinity of cosmic realities, as upon Sir Oliver Lodge's hierarchy of spirits. Huxley's coat of mail is his agnosticism: he does not know, and sees no way of knowing, the truth of many things about which some of his fellows are so certain.

Haeckel's faith is so robust that he has no trouble in seeing life arise from lifeless matter by easy natural processes. But it is extraordinary matter that he starts with – unorganized matter charged with such potency that it goes forward from step to step up the ladder, from compound to compound, each step a nearer approach to life, till what he names the monera, an organism without organs, is reached, then organized protoplasm, then the cell, then the functioning organism. The first bit of unicellular life is charged with such possibilities of development that the whole world of living things lies folded in it: man and all that lies below him, all the orders and suborders and species of the animal and vegetable kingdoms, are latent in the first bit of life-stuff that Haeckel invokes by the magic of words from inert matter.

For his start Haeckel goes back to the first hardening of the earth's crust, the formation of water in a fluid condition, and great changes in the carbonic-laden atmosphere. Under these conditions a series of complicated nitrogenous carbon compounds was formed, and these first produced albumen or protein. The molecules of albumen arranged themselves in a certain way, according to their unstable chemical attractions, in larger groups of molecules; and these combined to form still larger aggregates, and thus produced homogeneous plasma-granules. As these grew they divided, to form still larger plasma-granules of a homogeneous character, and the result is what he calls the monera, – the first bit of living unorganized matter, a cell without nuclei.

Out of this monera, by surface strain and chemical differentiation and other obscure processes, that wonder, the nuclear cell, arose – the architect of all living things on the globe. Our bodies, and the bodies of all other living beings, are simply multiplications of cells, all fundamentally the same, – the work of a complex microscopic mechanism that seems to know from the start the part it is to play in the world, and proceeds to build all the diversities of living forms that we know; but why, in the one case, it builds a flea, or a cat, or a monkey, or a man, and in another a flower, or a pine, or an oak, Haeckel's exposition does not help us to understand.

Do we know of anything in the laws of matter and force, as we see them in the non-living world, that would lead us to expect such novel results? Why the cell should build anything, since the colony of living cells that Dr. Carrel has kept going for a year or more builds nothing, but only multiplies its units, is a question which Haeckel's chemistry and physics will never be able to answer.

"The organs of a living body," he says, "perform their functions chiefly by virtue of their chemical composition." Undoubtedly, but what made it a living body and gave it organs? Of course the functioning of any bodily organ involves chemical processes, but do the processes determine the function? Do they assign one function to the liver, another to the kidneys, another to the heart? In other words, is the organizing effort that awakens in matter the result of chemistry and physics?

Do we not need to go outside of the material constituents of a living body to account for its purposive organization? Can we deduce an eye or an ear or a brain from any of the known chemical properties or their material elements? Does any living thing necessarily follow from its known chemical composition? Do the material constituents of the different parts of a machine determine the purpose and function of that machine? The function of an organ and the organ itself are the result of some unknown but intelligent power in the body as a whole.

I have no purpose to discredit Haeckel's science or his philosophy, but only to show how great is his scientific faith, – how much it presupposes, and what a burden it throws upon chemistry and physics. Like all the later philosophical biologists, he reaches a point in his argument when chemistry and physics become creative, while he fails to see that they differ at all in their activities from the chemistry and physics of inorganic matter. To be consistent he is forced to believe in the possibility of the artificial production of life. He helps himself out by endowing all matter with sensation and purpose, and thus its passage from one condition to another higher in the scale is easily accomplished.

Haeckel's manipulation of matter to get life will to many persons seem like a sleight-of-hand trick. One thing disappears, and at a word another entirely different takes its place. Now we see the solid lifeless crust of the earth, then we see water and carbon dioxide, then nitrogenous carbon compounds, then, presto! we have albumen or protoplasm, the physical basis of life. Out of protoplasm by a deft use of words comes the monera; another flourish of his pen and there is that marvel, the living cell, with its nucleus, its chromosome, its centrosome, and all its complicated, intelligent, and self -directed activities. This may be the road the creative energy traveled, since we have to have creative energy whether in matter or apart from it; but our scientific faith hesitates until these steps can be repeated in the laboratory and life appear at the behest of chemical reactions.

The scientific faith of mankind – faith in the universality of natural causation – is greatly on the increase; it is waxing in proportion as theological faith is waning; and if love of truth is to be our form of love of God, and if the conservation of human life and the amelioration of its conditions are to be our form of brotherly love, then the religion of a scientific age certainly has some redeeming features.