Facts and Theories of Modern Biology

New Zealand Tablet, 22 September 1921, Page 17

Facts and Theories of Modern Biology

(By U. A. Hauber, in the American Ecclesiastical Review.)

Theoretically science deals with natural phenomena, religion with the supernatural. Science is systematised and organised human knowledge; it has limitations, as all human things have, and is rightly supplemented by revealed truth.

In practice, however, scientists often make excursions beyond their acknowledged sphere of investigation, particularly when they do not believe in revealed religion. This is not surprising, since the human mind is not satisfied with anything short of an ultimate explanation of things. When, therefore, scientists of to-day advance opinions concerning the nature of God or the origin and destiny of man, they are within their rights, provided they do not present such opinions as the findings of science. They are speaking as men interested in facts that lie beyond the scope of science.

The danger is that one cannot separate the scientist from the man; whatever authority and prestige goes with the pronouncements of the scientist speaking ex cathedra clings to him when he steps from his official chair. And yet his researches in the natural world give him no better insight into the metaphysical or supernatural than that possessed by his less privileged brethern ; on the contrary, continued close application to the microscope is distinctly unfavorable to clearness of vision in the world outside.

The object of this paper is to present a bird's-eye view of one province of the domain of science, that of biology to indicate how and for what reasons workers therein so often transgress their legitimate boundaries and enter territory with which they are not familiar; and 'finally to suggest an attitude that Catholics may take toward biology, toward its genuine conclusions as well as toward its questionable theories.

At the University one takes a course of Embryology. Eggs are put in an incubator and taken out at regular intervals of about twelve hours to study their development. By means of microscopes and proper technique— latter itself a marvellous triumph of modern science and skill — one can observe all that goes on inside the egg. At first there are only a few microscopic cells, one just like the other, lying on the yolk. There is nothing particularly remarkable about them. But presently this little speck of living material begins to grow; that is, the original cells divide and multiply until there are hundreds of them. In other words the life in that egg increases in size. But it does no more than that. To begin "with, there is only a single layer of cells. This folds over nicely as a piece of cloth might be folded over by a tailor who intends to make a pair of trousers. Then there are two layers. The upper layer next gets a downward crease in it. This

crease gets deeper, sews itself together, as it were, along the top edge, and then cuts itself off from the main cloth and lo and behold we have a tube which is the primitive spinal cord with the brain at one end of it. While the upper layer has thus been initiating a nervous system, the lowersone folds in a similar manner, sews itself up, is cut off from the main piece of cloth, and our chick has a stomach and an intestine. In the meantime a third layer has been forming in between the other two. One part of this folds over, closes up, and there is a heart which promptly begins to beat. Another part becomes arranged in regular rows and forms the muscles of the back. In like manner the development of every organ and every part of that chick is accurately traced and described. A complete mastery of such intricate and minute details is one of the boasts of modern biological science.

I have taken pains to put in non-technical language this sample of the kind of work the student of biology does, for two reasons : first to help us realise that one has some very definite things to learn before he can claim to know biology, and that in the main these things are facts not hypotheses; secondly I wish to use this illustration to make clear what the theory of evolution means.

In brief, then, the evolutionist believes that just as the chick in the egg underwent a natural development from a very simple, unorganised condition until it arrived at the status of an adult barnyard fowl, so the whole class of animals we call birds descended or developed from a simple ancestor in natural fashion. Put as bluntly as that, it may seem unintelligible, almost ridiculous. It is indeed merely a hypothesis, but a hypothesis with facts to bolster it up. Unhappily the facts are all taken from the field of biology, itself and are with difficulty available to convince the sceptic.

Another task that the biologist has to accomplish before he is acknowledged worthy of the name is this: he must familiarize himself with the structure and functions of every type of living thing from the microscopic bacilli that float in the air and the minute slimy things that crawl in the mud,, to the highest forms of life of which the chick or the human being are representative examples. And when he has done that he has a complete series of living things, which, properly arranged, resemble strikingly the successive stages of a developing chick.

He must know still more. He must be familiar with the kinds of living beings that existed in past ages and are now extinct. Paleontologists have studied diligently former life on this globe as recorded in the rocks. They know its main features. They are not guessing or surmising. The man who is studying extinct life is studying facts as well attested as any facts can be. His researches have revealed a large number of very distinct periods of geologic history, each characterised by its own fauna and flora. We know the order of succession of these periods, even if we can only guess at the duration in years of each one of them. If we limit our survey to the vertebrate types, we find that the earliest strata yield only aquatic, fish-like forms; higher up, in the coal seams, amphibians, half -water half-land animals appear; still later the reptiles, and lastly in the Tertiary rocks the mammals, the highest forms, come to predominate. Now then, a mammal in its uterine development passes distinctly through the fish and amphibian stages before it takes on mammalian characteristics.

Such considerations suggest the evolutionary doctrine. No one claims that they establish it. But once accepted as a tentative working basis, everything seems to fall in line with the —vestigial organs, embryonic structures, connecting links; the biologist sets about looking for something .that should be there with almost uncanny foresight. The theory proves outpin much the same way as astronomical postulates resulted in the discovery of Neptune, or as new chemical compounds have been discovered after it was shown by theoretical formulas that they should exist. I may refer x to the origin, partial development) and then total absorption and disappearance of certain complex structures in the embryo. Father Wasmann was so impressed by one instance of this kind that he considered it alone indisputable proof of the evolution of the particular insect before him from another insect of an entirely different species. Any other

explanation would involve one in all sorts of absurdities and dilemmas. The biologist therefore is convinced that evolution does explain many things; peculiar facts, for the meaning of which no other theory has ever offered a solution.

So much for the point of view of the biotegist. The average naturalist looks upon evolution not as a theory but as a demonstrated fact. We need not quarrel with him. He has a right to his opinion. But, after all, the average naturalist is an eccentric sort of an individual. His tastes are queer, else he would not be what he is. And the habits formed in the pursuit of his hobby tend to accentuate his perversity. What are we as sane, unbiased men of affairs, whose judgment is kept in balance by continued contact with the real problems of —what are we to think of the fantastic speculations of these secluded denisons of the laboratory or meandering investigators of nature?

To avoid confusion in the use of terms we must distinguish well between the doctrine of evolution and the several attempts that have been made to explain the why and how of it. Darwinism is such an attempt; one of the first in the field and by far the most advertised; the one that brought the theory itself before the public and hence is* in popular apprehension inseparably bound up with evolution. Darwinism is the brand of pseudo-science dished out for us on the editorial page of the Sunday "yellow sheet." It is an unmitigated evil because it insists on a' material explanation of everything and emphasises ad nauseam the brute element in human nature. It is not evolution, it tries to be more thai* that —a philosophy of evolution.

We must realise, in other words, that there is a distinction between evolution in the abstract, and that concrete, living movement, fathered by atheistic scientists, which is the sole vehicle to-day for the dissemination of evolutionary ideas. The theory was born and reared in an irreligious atmosphere. Its present-day dress, its daily associates, do not recommend it. We shall have to divest it of these incidental accessories, if we wish to probe its essential nature. ,-

The first question to be considered then, is, what are we as Catholics, as defenders of the faith of our fathers, to think of the theory of evolution in the abstract, prescinding from its actual philosophical environment and unsavory associations.

We may emphatically insist that such a theory does not affect our idea of the creation of "matter, nor does it discuss the ultimate origin of life. These things are taken for granted, just as physics takes for granted the existence of matter and force. It can have nothing to say concerning the origin and ultimate nature of the principles according to which living things act. Like chemistry, it may discover the existence of certain laws and their mode of operation; it cannot say why these laws are there or how they came to be what they are.

The theory simply states that the organic world arrived at its present status through a natural process analogous to the development of the chick in the egg or of the oak from the acorn. It makes no attempt to account for the first forms of life. It does not deny that God created the world in its present form any more than the farmer denies that his corn was created by God in its full stature just because he, the farmer, saw it develop. - It does not affect our idea of God and the universe in the least; or, if it does, it is to emphasise His power and to give us a better conception of His manner of dealing with creatures. Looked at in this light, the matter is primarily of no concern at all to the priest, any more than is the subject of electricity or chemical affinity; it is exclusively a topic for the scientist. Those who are fearful lest such a doctrine is incompatible with Scripture and Revelation will do well to read carefully the first chapter of Genesis and to consult the reflections of St. Augustine and St. Gregory of Nyssa. St. Augustine clearly believed that God created living things inkpotent that is, put the germ of life into matter and then permitted it to develop of itself. The Scriptural ac- - count of the order of creation harmonizes with the idea strikingly that the evolutionist may actually quote it, in his favor. . Nevertheless, it is unquestionably dangerous to flirt

in so conciliatory a manner with a pure abstraction. The thing as it really exists to-day in the world xf modern thought is a philosophy of life, and a very reprehensible one. Let us examine it. Before beginning, it may be well to realise that for a priest a peculiar difficulty presents itself when he tries to evaluate intelligently this new school of thought. He has been trained in a school of his own which looks upon Revelation as the central fact of life. For him Christ is the dominant figure of history. The Incarnation gives unity and meaning to his philosophy. The decalogue is his guide, eternal happiness his goal. He is positive in his faith. He is not groping in the. dark. And modern thought is largely the negation of all this. -

And yet it is more than a mere negation; it is not pure chaos and destruction. The modern mind is building up a system of thought, a system of philosophy, that is really a unified whole, as clear-cut and well-defined in many respects as was the Scholastic system of the Middle Ages, and I may add far more dogmatic. Of course the central idea of this new edifice is not the Incarnation; its ultimate goal is not future happiness. It is a system of naturalism with man in the centre and evolution as its alpha and omega. Its conception of life is materialistic or pantheistic. Its pioneers and its present sponsors are in the main agnostics or avowed atheists. It claims not only - to be an.explanation of the proximate conditions in the organic world, but it proposes an ultimate philosophy that needs no God, that knows nothing of a free will, that demands a revision of the moral code, that has no patience with the doctrine of immortality.

And it is all this because its principal exponents were from the beginning hostile to the Church and they thought to have found in the new ideas a splendid weapon against her; a weapon that could be used with equal force to discredit the theologian and to arouse the imagination of the ignorant. It compelled the abandonment of age-long convictions hitherto considered inseparably bound up with our most cherished religious truths. If there is any truth in evolution, then God did not make the world as we see it to-day. It simply grew. Likewise, the world is more than six thousand years old. Man was not formed from the slime of the earth by the hand of God: he developed from it according to natural laws. Language was not given to man and miraculously confused at the tower of Babel: it developed in natural fashion from simple beginnings to the varied forms existing to-day. Religion was not given us from above: it was a natural by-product of mans developing mental life.

There is the whole.process in a nutshell. One or two of these propositions must indeed be accepted if we assent to the evolutionary idea. But by a trick familiar to politicians in a modern legislature, all the other propositions are attached to the main one as "riders," and the bewildered onlooker is told that there is no choice —take all or leave all.

The common mass of mankind does not follow the trend of argument by which such a philosophical system is built up; but the almost hypnotic influence that the spectacular achievements of modern science has gained over the mind of men, induces them to accept blindly whatever is proposed in the name of science. Moreover in our public schools, from the grades to the university, every text book from history and geography to literature, psychology, economics, linguistics, anthropology, ethics, and all the rest, begins with and is developed around the principle of evolution. There it finds unity of plan and purpose in what seems to the uninitiated a hopeless tangle of ideas and theories. The ordinary man or woman of our times, it is true, knows little of modern thought and its underlying philosophy. However, for us the practical importance of a knowledge of this kind is not so much in dealing with ordinary people as in being able to stand up before the leaders of modern thought, who through teachers and text books give the ordinary mortal unconsciously if you will, his world views, that is to say his creed and his ethics. This ordinary mortal fails to assimilate the real significance of the new thought. It is enough for him to know that he has authority for discarding the old order and , living according to the. new

moral code. In this way then the modern scientific viewpoint is producing a, tremendous. change in the life of the masses. It is one of the principal forces at work shaping

and moulding the modern type of man, Christian as well as' agnostic and atheist. It determines his mode of thinking, and thought is followed by action. Human events are merely the outward expression direct or indirect, of what is going on in the minds of men.

All this indicates at least one good reason why we should try to be informed concerning the trend of modern evolutionary philosophy; because it is a practical force in the social, economic, industrial, and religious life of our people.

The fact that we are not doing more than merely acquainting ourselves with these problems, is exceedingly to be regretted. At present the Catholic biologist is a rare individual. We should have dozens of them in the country, authorities in their field, doing original work. Then perhaps the rather questionable policy of indiscriminate condemnation might give way to constructive efforts; then we might succeed in having twentieth - centiiry philosophy transformed into a new structure, erected on the - solid foundations of Christianity rather than on the shifting sands of human weakness; and instead of permitting it to become the symbol of error and ungodliness, we could dedicate it to the spiritual service of mankind and to the honor and glory of God.

This paper would be very incomplete without some reference to man's place in the evolutionary scheme. Briefly stated, it comes to this: science knows nothing about the origin of man, his soul or his body. There is absolutely no data to reason from. The half dozen bones found in Java or near Heidelberg are of such indefinite character that even some of the most enthusiastic evolutionists do not accept them as of any value. Prehistoric man as far as known was essentially what he is to-day.

Why then does an overwhelming majority of modern biologists take the evolution of man as an established fact? Because he is, from the scientist's point of view. an animal; his body is certainly subject to the laws of animal life in its functions and in its development from egg to adult. The student takes for granted the uniformity of nature; if the whole animal world is subject to the laws of evolution, one cannot except man without doing violenco to nature.

The Catholic, in the presence of such arguments, need but keep the following points in mind. The human soul, intellect and will, are evidently excluded from any reasoning process that applies to the animal world. They belong to a different category. As to his body, Scripture tells us that it was made of the slime of the earth, and it seems, in the opinion'of some, to encourage the interpretation that the body was completed before the soul was breathed into it. St. Thomas clearly emphasised the opposite nature of the material and spiritual elements that together constitute the single creature called a man.

At any rate the Church has not condemned the proposition that man's body is the result of an evolutionary process initiated and guided by divine providence; that in fashioning man's body to become a fit habitation for the soul, God made use of natural laws, just as to-day He makes use of natural laws in the creation of each individual body. The idea may not appeal to our imagination. We do not like the idea of brute ancestors. Of course not. Did you ever see a two-month old human embryo? Did it appeal to your sense of propriety that you were once such a creature? That those mysterious forces of nature that gradually fashioned my body may have also entered into the formation of the first man, is not an essentially repugnant conception.

I am aware of the fact £hat while the above proposition is not condemned by the Church, the best one 'can say of it is that it is barely tolerated. ,The Church has a higher and more important mission than the teaching of science. Whether or not evolution is true has nothing to do with the salvation of souls. And if the Church finds that the transition from the old ideas to the new is accompanied by extreme danger to men's spiritual welfare, she raises a warning hand. She is conservative in this matter because she loves the soul more than the body. In natural science as well as in the supernatural order we cannot put new wine into old bottles without danger to the bottles. The theory of evolution received a great impetus during the last century precisely because its acceptance too often meant the rejection

of revealed religion. The Church is not blind to this very significant fact, and therefore bids Catholics go slow. Prudence must temper our zeal. The ground must be t prepared before such novel ideas can be sowed broadcast. Before that ground is prepared, we shall need a twentiethcentury St. Thomas; one who can so combine sacred and profane learning that both will draw benefit therefrom; one, perhaps, who can make Darwin and Huxley become to modern Catholic thought what Aristotle and Avicenna were to the Scholastics.