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Q.E.D.
Or New Light on the Doctrine of Creation
By
GEORGE McCREADY PRICE
_Professor of Chemistry and Physics, Lodi Academy, California
Author of "Outlines of Modern Science and Modern Christianity," "The Fundamentals of Geology," "God's Two Books," "Back to the Bible," "A Text-Book of General Science," etc._
"... and set you square with Genesis again." —Robert Browning.
1917
_To
WILLIAM CLEAVER WILKINSON Scholar, Critic, Poet and Christian Gentleman
This book is dedicated by one who owes to his advice and kindly sympathy more than can be expressed_
Preface
The great world disaster, ushered in with the dawn of that August morning in 1914, has already brought revolutionary changes in many departments of our thinking. But not the least of the surprises awaiting an amazed world, whenever attention can again be directed to such subjects, will be the realization that we have now definitely outgrown many notions in science and philosophy which in the old order of things were supposed to have been eternally settled.
There are but two theories regarding the origin of our world and of the various forms of plants and animals upon it, Creation and Evolution,—the latter assuming many modifications.
The essential idea of the Evolution theory is uniformity; that is, it seeks to show that life in all its various forms and manifestations probably originated by causes similar to or identical with forces and processes now prevailing. It teaches the absolute supremacy and the past continuity of natural law as now observed. It says that the changes now going on in our modern world have always been in action and that these present-day natural changes and processes are as much a part of the origin of things as anything that ever took place in the past. In short, Evolution as a philosophy of nature is an effort to smooth out all distinction between Creation and the ordinary processes of nature that are now under the regime of "natural law."
On the other hand, the essential idea of the doctrine of Creation is that, back at a period called the "beginning," forces and powers were brought into exercise and results were accomplished that have not since been exercised or accomplished. That is, the origin of the first organic forms, indeed of the whole world as we know it, was essentially and radically different from the ways in which these forms are perpetuated and the world sustained to-day. Time is in no way the essential idea in the problem. The question of how much time was occupied in the work of Creation is of no importance, neither is the question of how long ago it took place. The one essential idea is that in its nature Creation is essentially inscrutable; we can never hope to know just how it was accomplished; we cannot expect to know the process or the details, for we have nothing with which to measure it. The one essential thing in the doctrine of Creation is that the origin of our world and of the things upon it came about at some period of time in the past by a direct and unusual manifestation of Divine power; and that since this original Creation other and different forces and powers have prevailed to sustain and perpetuate the forms of life and indeed the entire world as then called into existence.
Accordingly, we might establish the Evolution doctrine by showing that matter can be made de novo, that energy can be created or increased in amount, that life can be made from the not-living, and that new and distinct forms of life can be produced in modern times,—all by natural law as now prevailing.
Or we can practically demonstrate the historical reality of a direct Creation at some time in the past, if we can show that the net results of all modern science tend to prove that the forces and processes now in operation can never account for the origin of things; that matter, and energy, and life, and the various forms of life must all have had an origin essentially different from anything now going on around us.
This indicates the line of argument adopted in the following pages.
The Evolution theory has been widely discussed and accepted in modern times. Indeed it has had a fair chance and an open field for several decades. What is the present situation of the controversy? The friends of the Bible and of old-fashioned Christianity need to know the real facts of the present situation.
Every now and then the news despatches report that the great Professor So-and-so has at last really produced life from the not-living, or has obtained some absolutely new type of life by some wonderful feat of breeding. Or some geologist or archaeologist has discovered in the earth the missing link which connects the higher forms of life with the lower, or which bridges over the gulf between man and the apes. Thus many people who get their "science" through the daily papers really believe that these long-looked-for proofs of Evolution have at last been demonstrated, and hence they receive without question the confident assertions of the camp followers of science published at space rates in the Sunday supplements that all intelligent men of to-day have long ago accepted the Evolution doctrine.
But in spite of the quick dissemination of news and the universal spread of education, it seems but a slow process for the really important discoveries of modern science to filter down through such media as the current periodicals to the rank and file of society. The situation seems to illustrate the old adage that a lie will travel round the world while truth is getting on her shoes. Thus it happens that the common people are still being taught in this second decade of the twentieth century many things that real scientists outgrew nearly a generation ago, and assertions are still being bandied around in the individual sciences which are wholly unwarranted by a general survey of the whole field of modern natural science. Indeed, in almost every one of the separate sciences the arguments upon which the theory of Evolution gained its popularity a generation or so ago are now known by the various specialists to have been blunders, or mistakes, or hasty conclusions of one kind or another. Thus the market value of all the various subsidiary stocks of the Evolution group has been steadily declining in their respective home markets, and now stands away below par; while strange to say the stock of the central holding company itself is still quoted at fictitiously high figures.
This curious—not to say deplorable—situation has developed largely because of the modern system of strict specialization in the various departments of science. Each scientist feels compelled by an unwritten but rigid code of professional ethics to confine himself strictly to the cultivation of the little plot of ground on which he happens to be working, and is forbidden to express an opinion about what he may know has been discovered on another plot of ground on which his neighbor is working, except by express permission. In other words, science teaching has now become strictly a matter of authority, this authority being vested in the various specialists; and nobody is permitted to look at it in a broad way, or to frame a general induction from the sum of all the facts of nature now discovered, under penalty of scientific excommunication. The scientific code of ethics forbids any general view of the woods: each man must confine himself to the observation of the particular tree in front of his own nose.
But these pages have been prepared under the idea that it is high time to take a more general survey of the geography, time to take our eyes off the various individual trees, and to look at the woods. Perhaps in some respects they may be regarded as too technical for ordinary readers. But if this is the case, it is because the writer had to choose between this somewhat technical treatment of the subject and the alternative danger of making loose and inaccurate statements or dealing in glittering generalities too vague to carry conviction. As it is, the writer is here trying to give directly to the general public the results of years of special research in correlating the data from many scattered departments of science,—results that most scientists would feel obliged to reserve for the select few of some learned society, to be published subsequently in the Reports of its "Transactions," and to find their way after years of delay into the main currents of human thought. But these dilatory methods of professional pedantry, miscalled "ethics," shall not longer be allowed to delay the publication of highly important principles which the public are entitled to know at once, and to know at first hand. Then, too, it is more than doubtful if any purely academic body could be found willing to become responsible for giving to the world conclusions so contrary to the vogue of the present day.
That these brief chapters may clear up the doubts of some, and encourage the faith of many, is the object of their publication in this non-professional form.
G. McC. P.
Contents
I. MATTER AND ITS ORIGIN 15 II. THE ORIGIN OF ENERGY 31 III. LIFE ONLY FROM LIFE 43 IV. THE CELL AND THE LESSONS IT TEACHES 57 V. WHAT IS A "SPECIES"? 68 VI. MENDELISM AND THE ORIGIN OF SPECIES 78 VII. GEOLOGY AND ITS LESSONS 99 VIII. CREATION AND THE CREATOR 125
I
MATTER AND ITS ORIGIN
I
When we were told by a prominent scientist just the other day that "electricity is now known to be molecular in structure," it almost took our breath away. And when we were informed that certain well-known chemical elements had been detected in the very act of being changed over into other well-known elements, with the prospect of such a transformation of the elements being quite the normal thing throughout nature, the very earth seemed to be slipping away from under our feet. Some of the closely related discoveries, such as the fact that the X-rays show a spectrum susceptible of examination, were not so disconcerting in themselves; but the marvellous pictures of the structure of the atom elicited by these discoveries made many good people almost question whether our venerable experimenters had not been indulging in pipe dreams amid their laboratory work.
Do we, then, begin to understand the real composition of matter? Does it have component parts, in the materialistic sense; or is what we call matter only a mysterious manifestation of energy? And if the latter be our answer, can we hope to settle the problem objectively and so conclusively that it will stay settled? In short, do we, regarding these border-line subjects between metaphysics and natural science, know anything more than our fathers and our grandfathers?
It will be convenient to consider these problems under two heads: the composition of matter, and the origin of matter.
II
1. It was long ago recognized that matter must be composed of particles which are driven farther apart by heat and are brought closer together by cold, thus laying the foundation for the theory of the molecular composition of matter. But not until the time of Dalton, about a hundred years ago, was it proved that the molecule itself, the unit of physical change, is capable of definite division into atoms, the units of chemical change. This conception of the molecules and atoms as the ultimate units of which matter is composed maintained its place until the discovery of radioactivity and its associated phenomena, about 1896; since which time we have definitely ascertained that even the atoms are separable into still smaller units, and that possibly these units are all alike. On this last possibility, it would surely be a most amazing fact if such multitudinous "properties" of bodies could be produced merely by variations in the arrangements of these ultimate units into atoms, or in some other way which produces vast differences in properties by combinations of units that are nevertheless mere duplicates of one another.
As hydrogen is the lightest of the elements, it has been a favorite theory with scientists that the various elements are all composed of combinations of hydrogen atoms. But since many of the elements have atomic weights which cannot be made exact multiples of that of hydrogen, it has been felt that there must be some other smaller unit than the hydrogen atom; or else that these hydrogen atoms themselves change in weight when they combine to form other atoms. But mass seems to be the one unchangeable characteristic of matter; hence it was felt that any change of weight is almost unthinkable, and so a solution was sought in the direction of still further dividing the hydrogen atom, the smallest unit concerned in chemical change, as then understood. But now the facts and principles brought to light in connection with the studies of radioactivity have settled it that we actually do have a much smaller unit than the hydrogen atom, one of only about 1/1760 its mass, in fact; and that this smallest of the small things of nature is none other than a particle of negative electricity, now called an electron.
That the atoms of all the elements must have a common unit of composition, that they behave as if composed of ultimate particles that may be regarded as duplicates of one another, has long been regarded as an inevitable conclusion from the Periodic Law of Mendeleef. This law says that the physical as well as the chemical properties of the various elements depend upon their atomic weights, or as it is stated in the language of mathematics, the properties of an element are functions of its atomic weight. This fact of the variation in the properties of elements in accord with their atomic weights has been even more strikingly illustrated by the behavior of discharges of electricity through rarified gases, as well as by the facts of radioactivity. To quote the words of Sir J.J. Thompson, "The transparency of bodies to Roentgen rays, to cathode rays, to the rays emitted by radioactive substances, the quality of the secondary radiation emitted by the different elements, are all determined by the atomic weight of the element."[1]
[Footnote 1: Encyclopaedia Britannica, Vol. XVII, 891. Cambridge Edition.]
Just recently we have had opened up before us a still more intimate inner-circle view of the composition of matter. H.G.J. Moseley, a young man only twenty-six years of age, at an English university, devised a method of examining the spectra of the various elements by means of the X-rays. He found in this way that the principal lines of these various spectra are connected by a remarkably simple arithmetical relationship; for when the elements are arranged in the order of their atomic weights, they show a graded advance from one to another equal to successive additions of the same electrical unit charge, thus indicating a real gamut of the elements that we can run up by adding or run down by subtracting the same unit of electrical charge. It is pitiable to have to record that next year this scientific genius was killed in the ill-fated Gallipoli expedition against Turkey.
Thus in many fairly independent ways we are brought around to this same idea of a common structure underlying all the many seeming diversities manifested by what we call matter.
The phenomena of radioactivity were discovered accidentally in 1896 by the French chemist Becquerel. Many investigators immediately began working along this promising line, and two years later Madam Curie, in association with others, discovered the new element radium. Soon it was discovered that radium and several other substances are continually giving off radiations at an enormous rate, that no change of chemical combination, no physical change of condition appears to have the slightest effect in slowing or increasing this discharge of emanations, while no scientific apparatus yet devised can detect any change in the substances left behind either in respect to weight or any other properties as the result of these enormous losses of energy. Accordingly some people not unnaturally were ready to draw the conclusion that those most firmly established laws of physics and chemistry, the laws of the conservation of energy and of matter, were overthrown by this astonishing behavior of these newly discovered substances. However, only a few more years of study and investigation were necessary to prove that this last conclusion was wholly unwarranted; and to-day these laws of the conservation of energy and of matter are more firmly established than ever.
The thing that has gone by the board is the old idea of the atoms as the indivisible and irreducible minima of the material universe. For not only do all the radioactive substances give off particles of helium gas positively electrified, but all bodies, no matter what their composition, can by suitable treatment, such as exposing them to ultra-violet light, or raising them to incandescence, be made to give off electrons or negatively charged particles, and these electrons are always the same no matter from what kind of substance they come. In a somewhat similar way, we always get positively electrified particles of the mass of the hydrogen atom, or about 1,760 times the mass of the electron, whenever we send an electric charge through a gas at very low pressure, no matter what the kind of gas. Whether or not these positive units will yet prove susceptible of being split up into smaller particles comparable to the electrons, is merely a subject for conjecture. We have no proof that they will. At the present time what we call matter seems to be composed of these positive units and of the electrons which are about 1/1760 as great; and in the present state of our knowledge these facts suffice to explain all the properties of matter. Thus we can either say that electricity is composed of matter, or say that matter is composed of electricity; and human language at best is such a clumsy vehicle of thought that scientifically and philosophically the one statement is as correct and as reasonable as the other.
And probably we shall never be able to learn any more than this. We have arrived at a sort of box-within-a-box theory of the make-up of matter. By a very elaborate system of unpacking, or by some violent external force that makes the inside burst open, as it were, we seem to be able to make pieces fly off from the atoms, these pieces being then projected into space with enormous force and velocity. There are theories galore of the structure of the atom; but as Prof. E.P. Lewis has said, most of these theories are so impossible as to be absurd, or so speculative that "they suggest no experimental tests for their validity."[2] Just at present Rutherford's theory of the structure of the atom is quite popular. This postulates a nucleus composed of a group of positive units and electrons, with an excess of the positive charges equal to half the atomic weight, with an equal number of electrons circulating about this nucleus in rings. Bohr's theory, which is not very different from this, has perhaps even more friends, and it is supported by the remarkable discoveries of the lamented Moseley. But we must not take such theories too seriously. As Kayser has said, any true theory of the make-up of the atoms must assume an absolutely full and perfect knowledge of all electrical and optical processes, and is therefore beyond our dreams. Or as Professor Planck said in his Columbia lectures, we are not entitled to hope that we shall ever be able to represent truly through any physical formulae the internal structure of the atom.
[Footnote 2: Nature, April 5, 1917.]
III
2. We must now take up the second phase of our subject, the problem of the origin of matter.
Before we knew anything of radioactivity we could have dismissed such a subject briefly by quoting the law of the conservation of matter, which says that matter can neither be created nor destroyed by any means known to science. By our knowledge of radioactivity we can make our answer a little more learned, a little less abrupt, but none the less discouraging to the advocate of the development hypothesis. We can tell how the elements of high atomic weight, such as uranium and thorium, are constantly giving off particles and are thus by loss or decomposition being changed over into other elements, such as radium, niton, polonium and lead. But our new knowledge compels us ultimately to give the same answer as before, namely, that we still do not know how matter ever could have originated, except that "in the beginning" it was called into existence by the fiat of Him whom we Christians worship as our God, the Creator. Thus we reach the conception of the universe as that of a great clock gradually running down, which is certainly the antithesis of that picture so long held before us by the advocates of the development theory.
Uranium is a rather rare element, though known for over a hundred years, and has an atomic weight of 238.5. In decomposing it gives off first a helium atom, weight 4; and after this action has been repeated three times the substance left is radium, atomic weight about 226.4. Thus radium is simply uranium after it has lost three helium atoms. Radium in its disintegration gives off three kinds of particles, namely, helium atoms (positively electrified), [Greek: b]-rays or electrons, and [Greek: g]-rays, the latter being identical with the X-rays, and having penetrating power sufficient to carry them through six inches of lead or a foot of solid iron. The final stage in this process of disintegration is the ordinary element lead, in which condition the atoms seem to have reached relative stability. Whether or not our stock of lead, with our other common elements that are not radioactive, was originally produced by the disintegration of these other elements, is merely a matter of conjecture. We know nothing at all about it.
The length of time it takes for half the atoms of an element to change is called its "life" or period. The periods of most of the radioactive substances have been calculated, that of uranium being very long. The calculated period of radium is 2,500 years, while that of polonium is only 202 days, and that of niton 5.6 days. These unquestioned facts, together with the enormous amount of heat evolved by the disintegration of these substances (that from radium being about 250,000 times the heat evolved by the combustion of carbon), have thrown a great deal of doubt upon the older estimates of the age of the earth.
The discussion of the details of these theories would be unprofitable. But through the mists of all these conflicting theories and probabilities two facts of tremendous importance for our modern world emerge in clear relief, namely, that the grand law of the conservation of matter still holds true, and hence that the matter of our world must have had an origin at some time in the past wholly different in degree and different in kind from any process going on around us that we call a natural process. These elements of high atomic weight that break down into others of lower atomic weight may be so rare because they have been about all used up in this process. At any rate, so far from revealing the origin of matter as a process now going on, these phenomena are an objective demonstration that all matter is more or less unstable and liable under some unknown but ever-acting force to lose some portion of that fund of energy with which it seems to have been primarily endowed. Not the evolution of matter but the degeneration of matter is the plain and unescapable lesson to be drawn from these facts. The varieties of matter may change greatly, and one variety or one chemical element may be transformed into another. But this transformation is by loss and not by gain. It is degeneration and not upward evolution that is now opened up before our astonished eyes by this peep into the ultimate laboratories of nature; and he is surely a blind observer who cannot read in these facts the grand truth that all this substance called matter with which science deals in her manifold studies must at some time in the past, I care not when, have been called into existence in some manner no longer operative. The past eternity of matter, as well as its progressive development from the simple to the complex, seems manifestly out of consideration in view of the facts as we now know them. There is no ambiguity in the evidence. So far as modern science can throw light on the question, there must have been a real Creation of the materials of which our world is composed, a Creation wholly different both in kind and in degree from any process now going on.
IV
A supposed objection has been raised to this view, based on the vastness of the universe as we now know it. Whether or not the universe is really infinite in extent, it is certainly of an extent that is practically infinite, so far as our powers of observation or of reasoning are concerned. But this practically infinite universe is not a bit harder to account for than would be a definitely limited universe, say of the size of our solar system. If the spectroscope shows that the far distant parts of the universe contain many of the same elements as are found in our solar system, we need not be surprised, since all are alike the work of the same Creator. Nor would this fact that the universe seems to be composed of similar materials throughout tend in any way to prove that all these parts of the universe were brought into existence at the same time, nor yet that our solar system was refashioned out of some of the common stock of the universe already on hand, as the nebular hypothesis supposes. For all that we can tell to the contrary, it would seem probable that the materials of our solar system were called into existence expressly for the position they are now occupying; and this seems to be the plain import of the record in Genesis. Of one thing, however, we can be certain,—these materials must at some time have been called into existence by methods or ways that are no longer in operation around us. "In the beginning God created the heaven and the earth."
V
Some remarks are necessary here regarding the homogeneousness of matter, or the idea that the various elements are composed of primordial units which are themselves alike, mere duplicates of each other. If this should prove to be really the case, as seems to be quite likely in the light of the facts given above, would it not be a veritable triumph for materialism? By no means. On the contrary, I think I can show in a very few words not only that this homogeneousness of matter is the only rational view of the composition of the material universe, but also that it is the only view consistent with Christian Theism and with the doctrine of Creation.
The theory of the atoms with their inherent and unchangeable properties, which prevailed during the greater part of the nineteenth century, naturally led us to look upon these properties as inherent in the things themselves. This was indeed materialism. This view, however, constantly impelled us to find out the essential differences between the various kinds of atoms, so as to "account for" their varying behaviors. And no matter how far we push such inquiries, this materialistic attitude of mind will control us so long as we think we are dealing with substances which are intrinsically different. If the differences are innate or inherent in the things themselves, we must naturally endeavor to find out why and how they are different; and no matter how far we go along this road we are always headed in the direction of stark materialism. On the other hand, to say that the "properties" of the atoms are not inherent in themselves, but are imposed on them by an external ceaselessly acting power, the will of the Creator, would be in full accord with Biblical theism; and then we might naturally say that the ultimate particles of which matter is composed may well be regarded as alike and mere duplicates of one another. And this, as we have seen, is just what modern discoveries in radioactivity are teaching us regarding the make-up of the substances that we call matter.
But an objection at once arises. How can these primordial units of which matter is composed behave so differently, if they are really alike, mere duplicates of one another?
We may not as yet be able to tell just why and how; but we have in the cells of which all plants and animals are composed an analogy which is almost perfect, if not quite.
These component units of organic matter, the individual cells, as will be explained later, seem physically and even chemically mere duplicates of one another. They may not all be of the same size; but they are all composed of protoplasm, and the protoplasm of plants cannot be distinguished from that of animals by any physical or chemical tests known to modern science. The protoplasm in the brain of a bird is the same as that in its toes; and no metaphysical subtilties about heredity have ever explained why the one does a different work from the other. The plain fact is that different cells, composed of identical protoplasm and structurally alike, act very differently; and there is no scientific reason based on innate properties that gives us even a glimmer of a reason why. We have searched a long time along this road; but there is no prospect of finding an explanation; we are merely running up a cul-de-sac with no view beyond. From the materialistic point of view, nobody knows why protoplasm acts as it does, least of all, why some masses of protoplasm act one way, and exact duplicates act differently. But if, on the other hand, we look beyond the facts and methods of physics and chemistry, and even beyond the most plausible theories of genetics, we can readily explain this remarkable action of the cells as the result of the will of an ever acting, omniscient, almighty God. Certainly nothing else is adequate to explain the behavior of living cells.
In a very similar way we must reason regarding the ultimate units of matter, call them what we will, electrons, corpuscles, or units of electricity. If these are mere duplicates of each other, as science now teaches, they not only indicate by this identity that they are "manufactured articles," as was long ago pointed out of the atoms and molecules, but they also indicate with all the force of a demonstration that nothing but an ever present omniscient Intelligence could keep these duplicates from always acting the same under similar external forces. If gold and carbon, iron and oxygen are at bottom composed of particles that are mere duplicates of each other, as seems to be the case, how can these elements and the six dozen or more others maintain their individuality throughout nature as we know they do, even in the far distant stars, except by the sleepless care of an Intelligence whose Word is as effective in one part of the universe as in another, and to whose Word these particles of matter can show no inertia and no disobedience, because they have no powers or properties except what He has imparted? This doctrine of the homogeneousness of matter is the antithesis of materialism. It is consistent only with the doctrine of an almighty and ever present God, and like many other facts which have been developed by modern scientific discoveries, it confirms the other primal doctrine of a literal Creation "in the beginning."
VI
The conclusion which our minds are forced to draw from the facts presented in this chapter is not doubtful, nor is it difficult to state. Matter is not now being brought into existence by any means that we call "natural." And yet the facts of radioactivity very positively forbid the past eternity of matter. Hence, the conclusion is syllogistic: matter must have originated at some time in the past by methods or means which are equivalent to a real Creation.
Thus far, at least, the record of Genesis is confirmed: "In the beginning God created."
II
THE ORIGIN OF ENERGY
I
What has been regarded by many as the greatest scientific triumph of modern times was worked out about the middle of the last century by James Prescott Joule and others, in determining that a certain amount of mechanical energy is exactly equivalent to a definite amount of heat. With this mechanical equivalent of heat all the various other forms of energy have also been correlated; until now we have the general law of the Conservation of Energy, which says that energy can be neither manufactured nor destroyed, but merely transformed and directed. And this magnificent law, like that of the conservation of matter, is strong evidence that there must have been a real Creation at some time in the long ago, different not merely in degree but in kind from anything known to modern science.
Joule worked out the mechanical equivalent of heat by means of his now famous experiment of churning water. He reasoned that if the heat produced by friction, etc., is really energy in another form, then the same amount of heat must always be generated by the expenditure of a given amount of motion or mechanical work. And this must be true, no matter whether this work is expended in overcoming the friction between wood on wood, iron on iron, or in any other conceivable way. Accordingly, he devised an experiment in which paddle wheels were made to rotate in a vessel of water by means of falling weights somewhat like the weights of a clock. The amount of work represented by the falling of the weights was easily calculated, and so was the amount of rise in temperature of the water caused by the friction of the water with the rotating paddle wheels. In various other ways he measured the amount of heat generated by a measured amount of work; and as the result of all his experiments (with very slight corrections made since by means of more exact apparatus), we now know that 778 foot pounds of work produce heat enough to raise one pound of water one degree Fahrenheit; or stated in the metric system, 427 kilogram meters of work will produce a calorie of heat.
Since these record-making experiments by Joule, the matter has been verified over and over again in all sorts of ways; and almost every kind of display of energy has been measured with more or less exactness. Even the amount of food oxidized in the human body is now known to be capable of correlation with the other forms of energy, though necessarily very minute exactness of measurement is scarcely attainable in this case. But no scientist of to-day doubts that all the physiological processes of animals or of plants conform exactly to the law of the conservation of energy that energy is neither created nor destroyed by any means known to science. In other words, the amount of energy in our world, if science can at all determine such a matter, seems to be a fixed quantity, gradually being dissipated into space, it is true, but momently replenished from the sun at exactly the same rate now as hundreds or thousands of years ago. And while this energy is in our world it is always capable of exact correlation in all of its multitudinous forms, and is transformable back and forth without increase and without loss.
On the discovery of the radioactive substances in 1896, some persons hastily concluded that the law of the conservation of energy was contradicted by the astonishing way in which these substances acted. But further and more accurate experiments have set this matter at rest, as indeed might have been expected; for the law of gravitation itself is not more immovably established in the make-up of the universe than this magnificent law that energy cannot be created by any means which we call natural.
In all ages there have been men who have spent their lives in the vain effort to invent a machine out of which work could constantly be obtained without the expenditure upon it of an equal amount of work. But the United States patent office has got so tired of receiving applications for patents based on this idea of perpetual motion that they have long since refused to issue any such patent where this principle is the manifest object; and I suppose the governments of other countries have taken a similar stand. And why? Because they know that energy cannot now be created by any device, no matter how ingenious; and they refuse to become a party to any scheme that seems to imply that this modern creation of energy is within the bounds of possibility.
Yet what is all this but a confirmation of the declaration long ago made that "the works were finished from the foundation of the world" (Heb. 4:3)? True, the energy we are constantly employing seems to come to us from the sun; but we must remember that the sun and its family of the solar system, including the earth, were all made at the same time, that they are bound together as parts of an indissoluble whole. Accordingly, no one can say that the total amount of energy called into existence at the creation of our solar system is being added to at the present time. At any rate, so far as modern science can judge of the matter, the total amount of energy available for our world is a fixed quantity; and its amount and the terms on which it was to be available for our use were fixed or finished "from the foundation of the world." While it is a very significant fact in this connection that with all the multiform speculations which have been made as to the physical source of the sun's heat, no explanation wholly satisfactory has yet been made as to how this energy coming to us from the sun is constantly replenished or maintained.
II
The desire to find a material cause for all phenomena is instinctive in the human mind, and has proved the chief impetus in a thousand discoveries. And yet, unless we are on our guard, it is liable to be a source of real error whenever we are dealing with the deeper problems of thought. For when we have pushed our way into the inner sanctuary of any department of nature, we almost invariably come upon a deep chasm that we can pass over only by building a bridge of words. Some of these verbal bridges have been decorated with very dignified names, such as "the luminiferous ether," "gravity," "chemical affinity"; and when we have shifted from the one side of the chasm to the other we impose upon the credulity of the public (and even ourselves) by giving out the impression that these words represent the real objective bridge on which we crossed.
In how many ways do we by our theories dodge the crucial problem of how energy is really transmitted, that is, how matter can act on distant matter across seemingly vacant space. Gravity, and indeed all the forms of the attractive forces, come under this head. True, we observe certain regularities in the way in which these phenomena occur, and the phenomenon at one place seems to be somehow dependent on some exercise of force at another place. And so we invent an ingenious theory, and fortify it all around with ponderous algebraic artillery for defense against all attack. And by persistent use of such theories we hypnotize ourselves into the belief that we are truly scientific in method, and are dealing with objective realities, and that these learned theories are something more than pretentious masks to hide our ignorance of real nature; when in reality these theories seem to be only a material screen to shield us from an embarrassing near view of the immediate action of God in all the various phenomena of the world; for not many find it a comfortable thought thus to live continuously beneath the great Taskmaster's eye.
The theory of the luminiferous ether as the medium of the transmission of light is one of these pretentious bridges of words. Our advancing knowledge of electro-magnetic phenomena may some day drive us back to a modified form of the corpuscular theory of light, and then we can throw this of the ether to the winds. In that case we would at least have a real material cause for the phenomena with which we deal. While the current theory of the ether has so many inconsistencies, and attempts to bridge over so many real chasms in our thinking that it seems truly astonishing to see it taught so long. By the theory of the ether the problems are not solved, they are merely postponed or evaded; for while solving one difficulty it creates a multitude of its own. How then are we better off than before without any such theory?
Being at liberty to invent any sort of qualities for their ether, scientists have tried to imagine such a substance as they think they need. The ether must be a kind of matter; but unlike any matter that we know of it cannot have weight, or else it would gravitate together here and there, thus becoming more abundant in some places than in others; whereas the need is for a material absolutely uniform throughout space, even throughout the interiors of solid bodies, such as the earth and the bodies upon the earth.
Another reason for supposing the ether to be a plenum, filling absolutely all space, is that it must be perfectly frictionless; and for this reason it cannot be composed of particles with spaces between them. It must be frictionless, for otherwise the planets would be retarded in their motions through space. The earth, for instance, is moving along its orbit at the rate of eighteen miles a second; and yet the ether does not pile up in front of it, nor is it made rarer in the wake of the earth. Moreover, during the thousands of years during which astronomers have been making observations absolutely no retardation has been detected in the motions of the earth or of any of the heavenly bodies, even to the smallest fraction of a second.
It is necessary to make the ether absolutely elastic and absolutely rigid. We are acquainted with many materials that are elastic, and with some that are comparatively rigid. But the elastic substances that we are acquainted with are not rigid, and the rigid substances are not elastic; and to assume such contradictory qualities in the ether transports us far beyond the bounds of experimental science.
These are but a few of the difficulties raised by the assumption of the ether as a real entity; but as there is no means of demonstrating its existence, except by arguing the necessity of having such a medium to transmit radiant energy, it follows that no multiplication of objections to the theory is likely to refute it in the minds of those who feel this necessity. Those who refuse to admit the possibility of "action at a distance," who insist on inventing a connecting material medium between every observed effect and some material object with which it seems to be in causal connection, will, I suppose, have to be allowed to exercise their ingenuity in any way to satisfy their minds, even though they may have to revise their theory with every fresh discovery in optics or radioactivity.
There are many other ingenious mental devices, like this of the ether, which seem to me only materialistic efforts to postpone or to dodge the real vital lessons to be read from natural phenomena,—efforts to push the real Cause back one step farther into the shadow,—a last desperate effort, in the face of the constantly accumulating evidence of modern knowledge that the great First Cause is far more intimately connected with life and motion than many are willing to believe. We have already mentioned gravity and the other attractive forces, such as cohesion and adhesion; but seemingly very few people have ever paused to consider how utterly inexplicable they still remain in any physical or materialistic sense.
It is easy to explain any form of a push in a physical way; but gravity is not a push but a pull. And how are we to explain the method by which a body can act where it is not, how explain in detail the way by which it can reach out and pull in toward itself another separated body, and exert this pull across the immeasurably wide fields of space? The law of inverse squares may tell us very accurately the manner in which the results are accomplished, for our Creator is a God of order. But there is no materialistic theory of the why of gravitation that is worth employing the time of sensible, truth-loving people. And we can rest assured that there never will be any such real "explanation," save that this is the way which the great Jehovah has ordained. Since such theories only explain the known in terms of the unknown, they can serve only as a sort of mental buffer or shield between us and the conception of the direct working of a personal God, whose word must always be as effective throughout the remotest corners of His universe as near at hand, for the very simple reason that matter has no "properties" which He has not imparted to it, and accordingly it can have no innate inertia or reluctance to act which God's word would need to overcome in order to induce it to act, even when this word operates across the wide fields of space. On this explanation these phenomena of "action at a distance" are at least intelligible; while to me, and I speak now as a scientist, they are intelligible in no other way.
III
There is another line of thought which has to do with living organisms, but which I shall beg leave to anticipate and bring in here at the close of this chapter, since it follows as a direct corollary from the law of the Conservation of Energy. Indeed, we might even term it the biological aspect of that law.
As we have seen, we can neither create energy nor destroy it; though we can lose it,—so far as this earth is concerned. The vast fund of energy that daily comes streaming to us from the sun is transmuted back and forth in a thousand ways, though little by little it is dissipated off into space, and we are dependent upon a fresh supply from the ever replenished fountain.
Just so, though in a somewhat idealistic sense, is it with what we may term vital energy. Cells, organisms, even whole races, are subject to degeneration and decay. They cannot acquire higher powers, though they may gradually lose what they already have; as Bateson has recently told us that whatever evolution there is must be by loss and not by gain. Water very easily runs down hill; but cannot go up hill in and of itself. Just so with the types of organic life. It was not merely an idle sneer of the witty Frenchman, that science has not yet explained how an ancestor can transmit what he has not got himself. He cannot always transmit all that he himself actually possesses of nature's gifts. Vitality becomes lowered, and the type degenerates. Weismann has emphasized this idea in his doctrine of "panmixia," or the withdrawal of selection, which always results in degeneration. Selection, artificial or natural, may serve to counteract this universal tendency of organic life, but only approximately. As Sir William Dawson says, "All things left to themselves tend to degenerate." Little by little the endowment of vitality bestowed upon our world at the beginning has, like radiant energy, been returned to God who gave it; but, unlike the case of radiant energy, the Creator has not established any regular source of vital supply from without, no elixir of life for organic nature in general. There is no longer within easy reach a tree of life from which we may pluck and eat and live forever. And as the individual grows old and dies, so do species and even whole tribes degenerate and become extinct.
"From scarped cliff and quarried stone She cries, 'A thousand types are gone.'"
The glorious flood of vitality, so prodigally lavished upon our world in the beginning, has been ebbing lower and lower; and the theory of organic nature steadily advancing from the lower to the higher is manifestly just as puerile as the old hope of creating energy by a perpetual-motion machine,—and a mistake of precisely the same nature. Both are contradicted by the magnificent law of the Conservation of Energy, which, as we have said, is only the scientific expression of the Scriptural statement that Creation is completed, so far as our world is concerned; though, as the "wages of sin," death has been decreed upon the individual, and degeneration more or less marked upon every organic type. The fossils of the past, as well as our own experience within the historic period, confirm the view already arrived at on other grounds that Creation is a completed work and is not now going on; and the universal testimony from organic nature is that degeneration and decay have marked the history of every living form. Just as the individual grows old and dies, so do species degenerate and become extinct.
III
LIFE ONLY FROM LIFE
"No biological generalization rests on a wider series of observations, or has been subjected to a more critical scrutiny, than that every living organism has come into existence from a living portion or portions of a pre-existing organism."[3]
"Was there anything so absurd as to believe that a number of atoms, by falling together of their own accord, could make a sprig of moss, a microbe, a living animal? ... It is utterly absurd.... Here scientific thought is compelled to accept the idea of creative power. Forty years ago I asked Liebig ... if he believed that the grass and flowers, which we saw around us, grew by mere mechanical force. He answered, 'No more than I could believe that a book of botany describing them could grow by mere chemical force.'"[4]
"Let them not imagine that any hocus-pocus of electricity or viscous fluids would make a living cell.... Nothing approaching to a cell of living creature has ever yet been made.... No artificial process whatever could make living matter out of dead."[5]
[Footnote 3: P.C. Mitchell, in Encyclopaedia Britannica, Vol. III, p. 952.]
[Footnote 4: Lord Kelvin in the London Times, May 4, 1903.]
[Footnote 5: Lord Kelvin, to a class of Medical Students, October 28, 1904.]
I
Ever since Rene Descartes, in his Holland laboratory, dissected the heads of great numbers of animals in order to discover the processes of imagination and memory, men have been seeking a physical or materialistic answer to such questions as, What is life? What is it to be alive? How shall we distinguish the living from the not-living?
No one of to-day, in the light of the correlation of vital processes with the general law of the conservation of energy, believes that life in plants and animals is a separate entity which may exist outside of and apart from matter. In a scientific sense, we only know life by its association with living matter, which in its simplest form is known as protoplasm. The latter has been termed the physical basis of life, and so far as we know every material living thing is composed wholly of protoplasm and of the structures which it has built up.
This grayish, viscid, slimy, semi-transparent, semi-fluid substance, similar to the white of an egg, is the most puzzling, the most wonderful material with which science has to deal. Chemically it is composed of various proteids, fats, carbohydrates, etc., and these in turn of but very few elements, all of which are common, and none of which are peculiar to protoplasm itself. And yet its essential properties, its mechanical as well as its chemical make-up, have baffled the resources of our wisest men with all their retorts and microscopes and other instruments of precision.
Protoplasm is essentially uniform and similar in appearance and properties wherever found, whether in the tissues of the human body, in a blade of grass, or in the green slime of a stagnant pool. And yet probably no two samples of protoplasm are ever exactly similar in all respects, though we may never be able to detect their precise differences. These differences are due to the fact that the stuff is alive, and within it are constantly going on those changes accompanying metabolism, or the building up and tearing down processes that always accompany life. All separate masses of protoplasm, such as the one-celled amoeba or the individual cells of our own bodies, are constantly taking in food and as constantly throwing off wastes. Hence, in the very nature of things, it is impossible to find any mass of protoplasm absolutely pure. And a further and impassable barrier to chemical analysis, or indeed to any adequate scientific examination, lies in the fact that we can never deal with protoplasm exactly as it is, since no analysis can be performed upon it without destroying its life. And yet even dead protoplasm, and especially its most characteristic constituent, proteid, has been found the most difficult material in the world to analyze, and nobody as yet pretends to know its exact chemical make-up.
The constant effort of natural science to press back the boundaries of the unknown is very liable to obscure some of the things most essential to any system of clear thinking regarding these matters. We are so prone to think that if only our microscopes were a little stronger, if only we could devise more effective methods of staining or of chemical analysis or chemical synthesis, we might really find out what life is, or what matter itself is; in short, that we might be able to solve in a scientific way the old, old riddle of existence. But already we have about reached the limits of the powers of the microscope; and even if we could devise a way of seeing the ultimate structures of which protoplasm is composed, how would we be any better off? Would we not have to attribute to each constituent of this living substance the properties which we now attribute to the whole?—that is, the properties which we attribute to masses of protoplasmic units, such as plants, or birds, or human beings?
We look at ourselves and we feel sure that we have a separate and real existence, that we are rationally conscious and are endowed with choice and free will. We can say almost as much for an intelligent bird or dog. But we hesitate to say how many of these powers or characteristics of free and independent personality can be assigned to the unicellular organisms, such as the amoeba or the corpuscles of our blood. These one-celled creatures are also alive, are just as truly alive as are those composed of many cells. Even the corpuscles of which our bodies are composed move, and eat, and grow, and seem really endowed with intelligence like the higher forms of life. Suppose we could go further than is now possible and could lay bare the ultimate make-up of the chromatin of these one-celled creatures, would we even then be able to prove that life with all its properties is inherent in these material components of the cells? In other words, would we really solve anything after all? Or would we not rather be compelled to acknowledge that the simplest, the most truly rational view of the question is that in living matter we have merely a special manifestation of the presence and the direct action of the God of nature which we cannot so readily recognize in not-living matter? This, it seems to me, is all that we really know, and all that we are likely ever to know.
When we examine carefully the differences between the living and the not-living, we see that the chief difference between them is in their origin. The matter of growth is not a real distinction; for crystals grow on the outside, while inorganic liquids grow by intussusception, as when a soluble substance is added to them, in very much the same way as an animal grows by the ingestion of food. Even movement is hardly an absolute distinction between the living and the not-living; for no movement can be detected in quiescent seeds, which may lie dormant for thousands of years; and on the other hand inorganic foams when brought into contact with liquids of different composition display movements that very closely simulate those of the living matter. Lastly, irritability, though so notably characteristic of living matter, is scarcely peculiar to it, for many inorganic substances seem almost as definitely responsive to external stimulation. But in the matter of their origin there is a real and a most fundamental difference. All living substance arises only from other substance already living. It cannot arise from the not-living; or at least it never has done so since the beginning of scientific observation, though on this point have been concentrated the learning and the laboratory technique of thousands of chemists and microscopists.
It may not be out of place to quote here from one of the classics dealing with this subject,—words that are just as true to-day as when first written nearly half a century ago:
"Let us place vividly in our imagination the picture of the two great kingdoms of nature,—the inorganic and the organic,—as these now stand in the light of the Law of Biogenesis. What essentially is involved in saying that there is no spontaneous generation of life? It is meant that the passage from the mineral world to the plant or animal world is hermetically sealed on the mineral side. This inorganic world is staked off from the living world by barriers that have never yet been crossed from within. No change of substance, no modification of environment, no chemistry, no electricity, nor any form of energy, nor any evolution, can endow a single atom of the mineral world with the attribute of life. Only by the bending down into this dead world of some living form can these dead atoms be gifted with the properties of vitality; without this preliminary contact with life they remain fixed in the inorganic sphere forever.
"It is a very mysterious law which guards in this way the portals of the living world. And if there is one thing in nature more worth pondering for its strangeness, it is the spectacle of this vast helpless world of the dead cut off from the living by the Law of Biogenesis, and denied forever the possibility of resurrection within itself. The physical laws may explain the inorganic world; the biological laws may account for the development of the organic. But of the point where they meet,—of that strange border-land between the dead and the living,—science is silent. It is as if God had placed everything in earth and heaven in the hands of nature, but had reserved a point at the genesis of life for His direct appearing."[6]
[Footnote 6: Henry Drummond, "Natural Law in the Spiritual World," Chapter I.]
It would be superfluous to emphasize further this great outstanding fact that the not-living cannot become the living by any of the processes which we call natural; and it would be presumptuous to attempt to emulate these eloquent words by seeking to emphasize the completeness with which this great Law of Biogenesis confirms the truth of a real Creation; for the supreme grandeur and importance of this law could be only obscured by so doing.
II
Perhaps some of the most impressive lessons on this subject will be found in connection with the history of the discovery of this great Law of Biogenesis, which says that life can come only from life. For by studying the history of the way in which this great Law has been established, we cannot fail to be impressed with the thought that back of all the complex array of living forms in our modern world which go on perpetuating themselves in orderly ways according to natural law, they could have originated only by a direct and real Creation, essentially and radically different from any processes now going on.
The wisest of the ancients in Greece and Rome knew nothing of this great law as we now know it. Aristotle, the embodiment of all that the ancient world knew of natural science, expressly taught that the lower forms of animals, such as fleas and worms, even mice and frogs, sprang up spontaneously from the moist earth. "All dry bodies," he declared, "which become damp, and all damp bodies which are dried, engender animal life." According to Vergil, bees are produced from the putrifying entrails of a young bull. Such were the teachings of all the Greeks and Romans, even of the scientists of the post-Reformation period, some of whom had accumulated a very considerable stock of knowledge concerning plants and animals.
And similar absurdities continued to be taught until comparatively modern times. Van Helmont, a celebrated alchemist physician who flourished during the brilliant reign of Louis XIV, wrote: "The smells which arise from the bottom of morasses produce frogs, slugs, leeches, grasses, and other things." As a recipe for producing a pot of mice offhand, he says that the only thing necessary is partly to fill a vessel with corn and plug up the mouth of the vessel with an old dirty shirt. In about twenty-one days, the ferment arising from the dirty shirt reacting with the odor from the corn will effect the transmutation of the wheat into mice. The doctor solemnly assures us that he himself had witnessed this wonderful fact, and continues, "The mice are born full-grown; there are both males and females. To reproduce the species it suffices to pair them."
"Scoop out a hole in a brick," he says further, "put into it some sweet basil, crushed, lay a second brick upon the first so that the hole may be completely covered. Expose the two bricks to the sun, and at the end of a few days the smell of the sweet basil, acting as a ferment, will change the herb into real scorpions."[7]
[Footnote 7: "Louis Pasteur, His Life and Labors," p. 89.]
Sir Thomas Browne, the famous author of "Religio Medici," had expressed a doubt as to whether mice may be bred by putrifaction; but another scientist, Alexander Ross, disposed of this suggestion by the following line of argument which was supposed to be conclusive as a reductio ad absurdum:
"So may he (Sir Thomas Browne) doubt whether in cheese and timber worms are generated; or if beetles and wasps in cows' dung; or if butterflies, locusts, grasshoppers, shell-fish, snails, eels, and such like, be procreated of putrid matter, which is apt to receive the form of that creature to which it is by formative power disposed. To question this is to question reason, sense and experience. If he doubts this let him go to Egypt, and there he will find the fields swarming with mice, begot of the mud of Nylus, to the great calamity of the in-habitants."[8]
[Footnote 8: Encyclopaedia Britannica, Vol. I, p. 64.]
When we remember that such nonsense constituted the wisdom of the scientific world only about two centuries ago, we begin to realize the fact that the doctrine of Biogenesis is indeed a very modern doctrine. But it may be well to ask in passing, How could the people of former ages understand or appreciate the great truth of Creation as we moderns are able to do?
The first important step toward the refutation of this old pagan doctrine of spontaneous generation was made by the Italian, Redi, in 1668. He noticed that flies are always present around decomposing meat before the appearance of maggots, and he devised an experiment to keep the flies away from actual contact with the meat. The meat putrified as usual, but did not breed maggots; while the same kind of meat exposed in open jars swarmed with them. He next placed some meat in a jar with some wire gauze over the top. The flies were attracted by the smell of the meat as usual, but could not reach the meat. Instead they laid their eggs upon the gauze, where they hatched in due time, while no maggots were generated in the meat. Thus from this time onward it became gradually understood that, at least in the case of all the larger and higher forms of life, Harvey's dictum, as announced some years previously, was true, and that life comes only from life.
But the invention of the microscope opened the way for a renewal of the controversy regarding the origin of life. Bacteria were discovered in 1683; and it was soon observed that no precautions with screens or other stoppers could prevent bacteria and other low organisms from breeding in myriads in every kind of organic matter. Here apparently was an entirely new foundation for the doctrine of spontaneous generation. It was freely admitted that all the higher forms of life arise only by process of natural generation from others of their own kind; but did not these microscopic organisms prove that there was "a perpetual abiogenetic fount by which the first steps in the evolution of living organisms continued to arise, under suitable conditions, from inorganic matter"?[9]
[Footnote 9: Encyclopaedia Britannica, Vol. I, p. 64.]
The famous "barnacle-geese" ought not to be omitted from any sketch of the vicissitudes of this doctrine of Biogenesis. An elaborate illustrated account covering their alleged natural history was printed in one of the early volumes of the Royal Society of London. Buds of a particular tree growing near the sea were described as producing barnacles, and these falling into the water were alleged to be transmuted into geese. Nor should we omit mention of Huxley's Bathybius Haeckelii, a slimy substance supposed to exist in great masses in the depths of the ocean and to consist of undifferentiated protoplasm, the exhaustless fountain from which all other forms of life had been derived. Not long after Huxley had given it a formal scientific name in 1868, it was discovered to be merely a precipitate of gypsum thrown down from sea water by alcohol, and thus a product of clumsy manipulation in the laboratory, instead of a natural product of the deep sea. The disappointment of those opposing biogenesis was severe; but the lesson is still of value to the world to-day.
The masterly work of Tyndall and Louis Pasteur in doing for the bacteria and protozoa what Redi had done for the larger organisms, is too much a matter of modern contemporary history to need recital here. Upon this great truth of life only from life is based all the recent advances in the treatment and prevention of germ diseases and all the triumphs of modern surgery. The housewife puts up canned fruit with the utmost confidence because she believes in this great Law of Biogenesis. It is because we all believe in it that we use antiseptics and fumigators and fly screens.
III
But what are the lessons to be learned from this great fact, and what bearing has this fact on the old Bible doctrine of a literal Creation?
Life comes now only from preexisting life. But at some time there was no life on the globe. It does not take any great exercise of "philosophic faith," as Huxley suggested, "to look beyond the abyss of geologically recorded time" and recognize that at this beginning of things there must have taken place a most wonderful event, essentially and radically different from anything now going on, namely, the beginning of organic life. But would not this be a real Creation in the old-fashioned sense of this term? We cannot avoid this conclusion; nor is there anything in either science or philosophy to indicate that this creation of the living from the not-living was confined to one mere speck of protoplasm. It is absolutely certain that it required a real Creation to produce life from the not-living at all; and it is just as reasonable that this exercise of creative power may have taken place in all parts of the earth at the same general time, as the Bible teaches. For if a Being saw fit to create life at all, why should He stop with one or two bits of protoplasmic units? An architect who can make his own bricks and other building material, can surely build what he desires out of these materials. Common sense tells us that, if the Creator really created life in the beginning, He did not stop with a few specks of protoplasm here and there over the earth. The ability to create life from the not-living implies the ability to make full-grown trees or birds or beasts in twenty-four hours, instead of waiting for months or years, as is usual at the present time.
As we have already found regarding matter and energy, so of life. The record in Genesis is confirmed, for modern science compels us to believe in Creation as the only possible origin of life,—a Creation entirely different from anything now going on, and one that can never be made to fit into any scheme of uniformitarian evolution.
IV
THE CELL AND THE LESSONS IT TEACHES
I
With his usual vigor and expressiveness Henry Drummond has given us a picture of the remarkable fact that the cells of all plants and animals are strikingly alike, especially the single cells from which all originate. It is easy for any one to distinguish between an oak, a palm tree, and a lichen, while a botanist will have elaborate scientific distinctions which he can discern between them. "But if the first young germs of these three plants are placed before him," says Drummond, and the botanist is called upon to define the difference, "he finds it impossible. He cannot even say which is which. Examined under the highest powers of the microscope, they yield no clue. Analyzed by the chemist, with all the appliances of his laboratory, they keep their secret.
"The same experiment can be tried with the embryos of animals. Take the ovule of the worm, the eagle, the elephant, and of man himself. Let the most skilled observer apply the most searching tests to distinguish the one from the other, and he will fail.
"But there is something more surprising still. Compare next the two sets of germs, the vegetable and the animal, and there is no shade of difference. Oak and palm, worm and man, all start in life together. No matter into what strangely different forms they may afterwards develop, no matter whether they are to live on sea or land, creep or fly, swim or walk, think or vegetate,—in the embryo, as it first meets the eye of science, they are indistinguishable. The apple which fell in Newton's garden, Newton's dog Diamond, and Newton himself, began life at the same point."[10]
In these remarks, of course, Drummond is dealing with the unicellular primal form, "as it first meets the eye of science"; and while certain slight peculiarities (such as the constant number of chromosomes) have been detected as characteristic of the cells of certain forms, yet for all practical purposes these words of Drummond are just as true to-day as when first written. Possibly it is because of a failure in our technique or from a lack of power in our microscopes that these wonderful protoplasmic units from which all living things originate seem identical. But it is equally possible that they are really identical in structure and in chemical composition, and that only the ever present watchcare of the great Author of nature directs the one to develop in a certain manner, "after its kind," and another in still another manner, "after its kind." At any rate, the protoplasm of which they are all alike composed is identical wherever found, so far as any scientific tests have yet been able to determine.
[Footnote 10: "Natural Law," Chapter X.]
II
There are many varieties of single cells known to science which maintain an independent individual existence. Among the unicellular plants are the bacteria, while the unicellular animals are known as the protozoa. And although perhaps I ought to apologize to the reader for seeming to anticipate here a part of the discussion of the problem of "species," yet it seems necessary to say a few words here regarding the "persistence" of these unicellular forms.
Among the diseases which have been proved to be due to protozoa are malaria, amoebic dysentery, and syphilis; while among the much larger number which are due to bacteria, bacilli, or other vegetable parasites, are cholera, typhoid fever, the plague, pneumonia, diphtheria, tuberculosis, and leprosy.
One of the difficulties attending the study of "species" among the higher forms of plants and animals has always been the length of time required to obtain any large number of generations on which to make observations. In the case of such plants as peas, wheat, corn, or indeed almost any form of plant life, it is only with difficulty that more than one generation a year can be obtained; and when two or more generations a year are produced, they are produced under more or less unnatural conditions. So that it takes almost a lifetime carefully to test and record in a thoroughly scientific way the results of any extensive experiments regarding variation and heredity.
In the case of mice or rats or rabbits or guinea pigs, many more generations can be obtained in a few years; but in the case of the larger kinds of animals the time taken for development to maturity and for gestation is often much prolonged; and scientific observation of an exact character has been in vogue for so short a time that there has always been the chance for advocates of evolution to take refuge under the plea that, if we only had longer and more carefully conducted observations, we could really see species in the making, one form becoming transformed into a distinct form, or perhaps giving rise to another and distinct form as an offshoot.
But in the case of the bacteria and protozoa, we can have a new generation every hour or so, sometimes every half hour. True, these forms of minute life have been under observation for only a few years; but their effects have in many cases been observed for almost the entire length of human history. No physician would tolerate the suggestion that the bacillus of cholera can produce the symptoms of diphtheria, or the tubercle bacillus produce the symptoms of leprosy. Nor will any scientist deny that such diseases as the plague, tuberculosis, or diphtheria are identical with diseases which ravaged Rome or Greece or Egypt thousands of years ago. And as the symptoms of these modern diseases are similar to those recorded by acute observers in Greece or Egypt two thousand years or more ago, we must conclude that the organisms causing these symptoms are doubtless identical. Similar remarks might be made regarding fermentation and other forms of decay.
In the case of a form of bacteria which reaches maturity and redivides in half an hour, the number of individual forms existing at the end of two days would need about twenty-eight figures to represent it. Doubtless these forms never multiply at this rate uninterruptedly for any great length of time, or else they would occupy the whole world to the exclusion of every other form of life. And doubtless instances arise where the period of growth to maturity and division is prolonged to several times the half-hour period mentioned above. But in any case, as we contemplate the length of time during which such well marked diseases as diphtheria, leprosy, or the plague have been known, we must acknowledge that these unicellular forms seem to breed true during a most astonishingly long period. How can we deny that this "persistence" of these unicellular forms constitutes a very strong argument in favor of the "fixity" of these forms?
III
But we must proceed to examine the behavior of the various kinds of cells of which the various multicellular organisms are composed.
Plants were known to be composed of cells, and their cells were studied and described some years before it was understood that animals also are composed of cells as units. Even then, however, the first propounders of the cell theory (Schleiden and Schwann) had no clear or accurate idea of the origin of cells, or of their essential characters and structure. As to origin, they supposed that cells arose by a sort of crystallization from a mother liquor; and as to structure, they looked upon the cell-wall as the really important part, the fluid contents being quite subordinate. Hugo von Mohl (1846) applied to the fluid contents of the cell the term "protoplasm," and Max Schultze (1861) showed that this protoplasm is really identical in all organisms, plants and animals, also that the cell-wall is frequently absent in many animal tissues and in many unicellular forms, indicating that the protoplasm is the really important substance. By this time also it had become known that cells never arise de novo, as had been supposed by the earlier investigators, but that cells arise only by division of preexisting cells; or as Rudolf Virchow (1858) expressed it, "omnis cellula e cellulā."
It was, however, many years before the details of the growth and reproduction of the cells (cell-division) became well understood. Not until the last quarter of the nineteenth century was it settled that the nucleus of the cell is also a supremely important part; but finally in 1882 Flemming was able to extend Virchow's aphorism to the nucleus also: omnis nucleus e nucleo.
Since these discoveries our knowledge of the methods of cell-division has much increased; and in the light of our modern knowledge of these matters there is nothing in all nature more marvellous than the regular orderly way in which cells reproduce themselves according to fixed laws. Certain cells in the developing embryo, for example, are early set apart for a particular function or for building certain structures, and thereafter are never diverted from this duty so as to do a different work or produce a different kind of structure. In the young embryo certain structures arise at certain predestined times in particular places, and only there and out of these cells alone. As to why it should be so, we cannot tell, save as the result of deliberate design and as an expression of the order-loving mind of the God of nature. In the words of one of the greatest of modern authorities, "We still do not know why a certain cell becomes a gland-cell, another a gangleon-cell; why one cell gives rise to smooth muscle-fiber, while a neighbor forms voluntary muscle.... It is daily becoming more apparent that epigenesis with the three layers of the germ furnishes no explanation of developmental phenomena."[11]
[Footnote 11: Nature, May 23, 1901.]
In accordance with the general principle of a division of labor, certain cells become early set apart to particular functions, and in accordance with the varying demands of these functions the developing cells may become greatly changed in form and in vital characteristics. That is, one cell specializes, let us say, in secretion, another in contractility, another in receiving and carrying stimuli, etc. In this way we will have the gland-cell, the muscle-cell, and the nerve-cell, each cell destined to produce one of these organs developing others "after its kind," the result being that it is soon surrounded with numerous companions doing a similar work, making up in this way a particular tissue or organ—gland, muscle, or nerve—which in the aggregate has for its function the work of the particular cells composing it.
But the important thing for us to remember in this connection is that when cells once become thus differentiated off and dedicated to any particular function, they can never grow or develop into any distinctly different type of cell with other and different functions. It is true that through pathologic degeneration the form and even the function of cells may become greatly changed; but never does it amount to a complete metamorphosis or complete transformation into another distinctly different type.
This is a very important principle, and it contains so many lessons for us bearing on the philosophy of life in general that it may be allowable to establish this fact by several somewhat lengthy quotations from standard authorities.
The first will be from one of the highest authorities on embryology, Charles Sedgwick Minot, of Harvard:
"In accordance with this law [of differentiation] we encounter no instances, either in normal or pathological development, of the transformation of a cell of one kind of tissue into a cell of another kind of tissue; and further we encounter no instances of a differentiated cell being transformed back into an undifferentiated cell of the embryonic type with varied potentialities."[12]
Again, we have the following from one of the foremost pathologists, as to the strict and rather narrow limits of even pathologic change:
"Epithelium and gland cells ... never become converted into bone or cartilage, or vice versa; while, again, it may be laid down that among epiblastic and hypoblastic tissues, on the one hand, and mesoblastic tissues on the other, there is no new development or metaplasia of the most highly specialized tissues from less specialized tissues; a simple epithelium cannot in the vertebrate give rise to more complex glandular tissue, or to nerve cells; in regeneration of epithelium there is no new formation of hair roots or cutaneous glands. The cells of white fibrous connective tissue have not been seen to form striated or even non-striated muscle."[13]
[Footnote 12: Science, March 29, 1901, p. 490.]
[Footnote 13: J.G. Adami, "Principles of Pathology," pp. 641-642.]
As implied by these quotations, a constant and progressive differentiation of cells prevails in the developing embryo; and when complete, certain groups of cells act as specialists in doing only certain kinds of work for the body. These cells maintain their specific characters in a very remarkable degree under normal conditions. Under various abnormal conditions, however, these cells may become modified as to functions, so that cells or tissues of one type may assume more or less completely the characters of another type. "But," as a very high authority declares, "the limitations in this change in type are strictly drawn, so that one type can assume only the characters of another which is closely related to it. This change of one form of closely related tissue into another is called metaplasia....
"When differentiation has advanced so that such distinct types of tissue have been formed as connective tissue, epithelium, muscle, nerve, these do not again merge through metaplasia. There is no evidence that mesoblastic tissues can be converted into those of the epiblastic or hypoblastic type, or vice versa."[14]
[Footnote 14: Delafield and Prudden, "Text-Book of Pathology," pp. 62, 63.]
This modification of function among the cells which sometimes goes on in the developing embryo, or under pathologic conditions, is very closely analogous to the variation which goes on among species of animals and plants. But, as we shall see later, there is a well marked limit to this variation among species, just as we see there is in the variations among the cells. Practically the same general laws hold good in each case.
If cells did not maintain their ancestral characters in a very remarkable way, what would be the use of grafting a good kind of fruit onto a stock of poorer quality? The very permanency of the grafts thus produced is proof of the persistency with which cells reproduce only "after their kind."
IV
How can we fail to see the bearings of these facts on the doctrine of the transformation of species among ordinary plants and animals, which are merely isolated and self-contained groups of cells? Do not these facts constitute strong presumptive evidence that among animals and plants, though there may be variation in plenty within certain limits, perhaps within even much wider limits than used to be thought possible, yet among these distinct organisms, little and big, new forms develop only after their ancestral type, in full accord with the record given in the first chapter of the Bible?
But we are now prepared to examine in more detail the facts as now known to modern science regarding "species" of plants and animals.
V
WHAT IS A "SPECIES"?
I
We have seen that there is no way to account for the origin of matter, of energy, or of life, except by postulating a real Creation.
We have seen that cells continue to maintain their identity, and reproduce only "after their kind."
We must now deal with the higher forms of cell aggregates, which we call plants and animals. It has long been held that these at least are mutable, that one kind of plant or of animal may in the course of ages be transformed into a distinctly different type; and of late years there has accumulated a very voluminous literature dealing with the various intricacies of this problem of the origin of species. How can we deal with such a large subject in a brief way? It seems best to confine our attention in this chapter to an attempt to answer the question, What is a species? and are "species" natural groups clearly delimited by nature?
II
The term "species" was at first used very loosely by scientific writers. It meant very little more than our vague word kind does at the present time. Not until the time of Linnaeus (1707-1778) did the term acquire a definite and precise meaning. The aphorism of the great botanist, "species tot sunt diversae quot diversae formae ab initio sunt creatae"—"just so many species are to be reckoned as there were forms created in the beginning,"—was at least an attempt to use the term in a well-defined sense. Of course, this definition assumed the "fixity" of species; but with the wide prevalence of the views of Darwin and his followers the term "species" has fallen into disrepute, and is now regarded by many as only an artificial rank in classification corresponding to no objective reality in the natural world. Some writers, as Lankester, have found so much fault with the term as to urge its complete abandonment in scientific literature. This is logical enough from the standpoint of Darwinism; for if the latter be true there ought indeed to be such a swamping of every incipient "species" as to make one kind blend with others all around it in the classification series.
But since the term has by no means been discarded, we must endeavor to determine the sense in which it continues to be used in good scientific literature.
"A species," says Huxley, "is the smallest group to which distinct and invariable characters can be assigned." The Standard Dictionary says that the term is used for "a classificatory group of animals or plants subordinate to a genus, and having members that differ among themselves only in minor details of proportion and color, and are capable of fertile interbreeding indefinitely."
The latter authority also adds:
"In the kingdoms of organic nature species is founded on identity of form and structure, and specifically characterized by the power of the individuals to produce beings like themselves, who are in turn productive."
To put the matter still more definitely before the reader, we quote the following from a well-known scientist whose writings on the subject of evolution have had a wide circulation:
"There are two bases on which species may be founded. Species may be based on form, morphological species; or they may be based on reproductive functions, physiological species. By the one method a certain amount of difference of form, structure, and habit, constitutes species; according to the other, if the two kinds breed freely with each other and the offspring is indefinitely fertile, the kinds are called varieties, but if they do not they are called species."[15]
This author adds that this physiological test, as to whether or not the kinds are cross fertile, "is regarded as a most important test of true species, as contrasted with varieties or races."
[Footnote 15: Joseph Le Conte, "Evolution and Religious Thought," p. 233.]
III
When we look at the matter in this light, it is very evident that there are multitudes of long recognized specific distinctions that ought to be discarded. For instance, there are some twenty odd "species" of wild pigs scattered over the Old World, which Flower and Lydekker assure us would probably "breed freely together."[16] The yak and the zebu of India, and the bison of America, would on this basis have to be surrendered, for it is well known that they will all breed freely with the common domestic cattle, as well as with one another. Perhaps all or nearly all of the dozen or more "species" of the genus Bos would thus be included together. All of the dogs, wolves, and others of the Canidae might thus be considered as fundamentally a unit. The cats (Felidae) are well known to breed freely together, Karl Hagenbeck of Hamburg having crossed lions and tigers as well as others of the family. Practically all of the bears have been crossed repeatedly, and the progeny of these and other crosses are quite familiar sights at the London Zooelogical Gardens. Among the lower forms of life even more surprising results have been attained by Thomas Hunt Morgan and others.
[Footnote 16: "Mammals Living and Extinct," pp. 284-285.]
It would, however, be a very hasty conclusion to say on the basis of these facts that there are no natural limitations to groups of animals and plants. But we are entirely warranted in concluding from these facts that in very many cases, perhaps in most, our system of taxonomic classification of animals and plants has gone altogether too far, and that scientists have erected specific distinctions which are wholly uncalled for and which confuse and obscure the main issues of the species problem. Among the workers in botany and in every department of zooelogy there have always been the "splitters" and the "lumpers," as they are familiarly called; the former insisting on the most minute distinctions between their "species," thus multiplying them; the latter being more liberal and tending to diminish the number of species in any given group. For a generation or more in the recent past the "splitters" had things pretty much their own way; but of late there is a growing tendency to frown down the mania for creating new names. Even yet it is with the utmost reluctance that long established specific distinctions are surrendered, as is illustrated in the case of the mammoth, which is acknowledged by some of the very best authorities to be really indistinguishable from the modern Asiatic elephant. Several fossil bears were long listed in scientific books; but they are all acknowledged now to be identical with the modern grizzly, and as we have already intimated all the modern ones ought to be put together. These modern rationalizing methods have made but a slight impression on the vast complex of the fossil plants and animals, affecting the names of only a few of the larger and better known forms. In the realm of invertebrate palaeontology, however, the "splitters" are still holding high carnival, in spite of the efforts of some very prominent scientists in the opposite direction. For palaeontologists still follow the irrational course of inventing a new name, specific or even generic, for a form that happens to be found in a kind of rock widely separated as to "age" from the other beds where similar forms are accustomed to be found. As Angelo Heilprin expresses it, "It is practically certain that numerous forms of life, exhibiting no distinctive characters of their own, are constituted into distinct species for no other reason than that they occur in formations widely separated from those holding their nearest kin."[17]
As a result of these methods this same author declares: "It is by no means improbable that many of the older genera, now recognized as distinct by reason of our imperfect knowledge concerning their true relationships, have in reality representatives living in the modern seas."[18] |
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