IV

Biologists are coming more and more to recognize some unknown factor

in evolution, probably some unknowable factor. The four factors of

Osborn--heredity, ontogeny, environment, selection--play upon and

modify endlessly the new form when it is started, but what about the

original start? Whence comes this inborn momentum, this evolutionary

send-off? What or who set the whole grand process going?

Bergson sees an internal psychological principle of development,

hence the name of his book, "Creative Evolution." Osborn uses the

word "directed." Certain characters, he says, are adaptive or suited

to their purpose from the start; they do not have to be fitted to

their place by natural selection. Huxley uses the word

"predestined"--all the life of the globe and all the starry hosts of

heaven are working out in boundless space and in endless time "their

predestined course of evolution." Darwin must have had in mind the

same mysterious something when he said that man had risen to the

very summit of the animal scale, but not through his own exertions.

Not by his own will or exertion, surely, any more than the embryo in

its mother's womb develops into the full-grown child by its own

exertion or than our temperaments and complexions and statures are

matters of our own wills and choice. Something greater than man and

before him, to which he sustains the relation that the unborn child

sustains to its mother, must enter into our thought of his origin

and development.

The great evolutionists have been very cautious about seeking to go

behind evolution and name the Primal Cause. In such an attempt

science would at once be beyond soundings. Darwin and Huxley were

reverent, truth-loving men, but they hesitated as men of science to

put themselves in a position where no step could be taken.

Slowly man emerges out of the abyss of geologic time into the dawn

of history, and science gropes about like a man feeling his way in

the dark or, at most, by the aid now and then of a dim flash of

light, to trace the path he has come. He has surely arrived, and we

are, I believe, safe in saying he has come by the way of the lower

orders; but the precise forms through which he has come, the houses

in which he has tarried by the way, and all the adventures and

vicissitudes that befell him on the journey--can we ever hope to

know these things? In any case, man has his antecedents; life has

its antecedents; every beat of one's heart has its antecedent cause,

which again has its antecedent. We can thus traverse the chain of

causation only to find it is an endless chain; the separate links we

can examine, but the first link or the last we see, by the very

nature of things, and the laws of our own minds, must forever elude

us. Science cannot admit of a break in the chain of causation,

cannot admit that miracles or the supernatural in the old sense, as

external and arbitrary interference with the natural order, can play

or ever have played any part in this universe. Yet science has to

postulate a First Cause when it knows, or metaphysics knows for it,

that with the Infinite there can be no first and no last, no

beginning and no ending, only endless succession.

To science man is not a fallen creature, but a many times risen

creature and all the good of the universe centres in him. The mind

that pervades all nature and is active in plant and animal alike

first comes to know itself and regard itself and achieve

intellectual appreciation in man. While all nature below man is wise

only to its own ends and goes its appointed way as void of

self-consciousness as the stone that falls or the wind that blows,

the mind of man attains to disinterested wisdom and turns upon

itself and upon the universe the power of objective thought; it

alone achieves understanding.

In our studies of life and of the universe as soon as we begin to

bridge chasms by an appeal to the miraculous, or to the

extra-natural powers, we are traitors to the scientific spirit which

we seek to serve. There are many things that science cannot explain.

Perhaps I may say that it cannot give the ultimate explanation of

anything. It can do little more than tell us of the action, the

interaction, and the reaction of things, but of the things

themselves, their origin and ultimate nature, or the source of the

laws that govern them, what does it or what can it know?

Man is the heir of all the geologic ages; he inherits the earth

after countless generations of animals and plants, and the

beneficent forces of wind and rain, air and sky, have in the course

of millions of years prepared it for him. His body has been built

for him through the lives and struggles of the countless beings who

are in the line of his long descent; his mind is equally an

accumulated inheritance of the mental growth of the myriads of

thinking men and unthinking animals that went before him. In the

forms of his humbler forebears he has himself lived and died myriads

of times to make ready the soil that nurses and sustains him to-day.

He is a debtor to Cambrian and Silurian times, to the dragons and

saurians and mastodons that have roamed over the earth. Indeed, what

is there or has there been in the universe that he is not indebted

to? The remotest star that shines has sent a ray that has entered

into his life. All things are under his feet, and the keys of the

heavens are in his hands.

V

One would fain arrive at some concrete belief or image of his line

of descent in geologic time as he does in the historic period. But

how hard it is to do so! Can we form any mental picture of the

actual animal forms that the manward impulse has traveled through?

With all the light that palaeontology throws upon the animal life of

the past, can we see where amid the revel of these bizarre forms our

ancestor hid himself? Can we see him as a reptile in the slime of

the jungle or in the waters of the Mesozoic world? What was he like

or what akin to? What mark or sign was there upon him at that time

of the future that was before him? Can we see him as a fish in the

old Devonian seas or lakes? Was he a big fish or a little fish? The

primitive fishes were mostly of the shark kind. Is there any

connection between that fact and the human sharks of to-day? Much

less can one picture to one's self what his ancestor was like in the

age of the invertebrates, amid the trilobites, etc., of the earlier

Palaeozoic seas. But we must go back even earlier than that, back to

unicellular life and to original protoplasm, and finally back to

fiery nebulous matter. What can we make of it all by way of concrete

conception of what actually took place--of the visible, eating,

warring, breeding animal forms in whose safekeeping our heritage

lay? Nothing. We are not merely at sea, we are in abysmal depths,

and the darkness is so thick we can cut it.

We meet the same difficulty when we try to figure to ourselves the

line of descent of any of the animal forms of to-day. How did they

escape the world-wild catastrophe of earlier geologic times? Or

did the creative impulse bank upon life as a whole and never become

bankrupt, no matter what special lines or forms failed?

The first appearance of the primates is in Eocene times and the

anthropoid apes in the Miocene, probably five millions of years ago.

The form which may have been in our line of descent, the

Dryopithecus, later appears to have become extinct. Did our fate

hang upon the success of any of these forms? The monkeys and

anthropoid apes appeared at the same time in different countries.

Nature seems to have been making preliminary studies of man in these

various forms, but when and where she hit upon the form that she

perfected in man, who knows?

The horse appears to have been evolved in North America, true cattle

in Asia, elephants in Africa. Can we narrow their line of descent

down to a single pair for each? Many forms allied to the horse

appeared in Europe and Asia in Miocene times. We find monkeys in

different parts of the world in the same geologic horizons; did they

all have a common origin?

Life's apprenticeship has been a long one. The earlier forms of

vertebrate life were very large; later they became very small.

Nature seems to have experimented with bulk, as if she thought size

would win in the race. Hence those huge uncouth forms among the

reptiles and early mammals. The scheme did not work well; bulk was

not the thing, after all. Most of the gigantic forms became extinct.

Then she tried smaller and more agile forms with larger brains--less

flesh and more wit. On this line Nature continued to work till she

produced her masterpiece in man--a rather feeble and nearly

weaponless animal, but with an intangible armory of weapons and

tools in his brain that enables him to put all creatures under his

feet.