[4] Whetham. _The Foundations of Science_, p. 50.
[5] H. L. Sulman, at the Sir John Ca.s.s Inst.i.tute, November 29th, 1911.
[6] Presidential Address to British a.s.sociation, 1904.
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CHAPTER VIII
LATER SCIENCE (_continued_)
We have spoken of what science has recently been doing in the investigation of the const.i.tution of matter; we have now to talk of its researches into the nature of Life.
The discovery that all plant and animal life is developed from living cells was made, as we have already stated, more than seventy years ago.
Since then our knowledge of the formation and history of these cells has been continually growing. The size of cells varies, but as a rule they are very minute. They consist of what is termed protoplasm. At one time it was supposed that protoplasm was structureless. Now it is known that the protoplasmic cell contains a nucleus and a surrounding body. Moreover, the nucleus, or small spot in the centre, has within it a spiral structure of a very complicated kind. Every cell is derived from a pre-existing cell by a process of division, the two resulting cells being apparently identical with the parent cell. {77} The cells possess the power of a.s.similating other cells or fragments of cells. As they grow they move and go in search of food and light and air and moisture. They exhibit feeling, and shrink as if in pain.
Spots specially sensitive to vibrations become eyes and ears; and thus the various organs and faculties are evolved under the stimulating influence of environment. The progress, so far as it is physical, can be traced from the lowest blue-green algae right up to man. And all throughout, in so far as their chemical composition is concerned, the const.i.tuent elements of the living structure are the same. It is said to be practically impossible to distinguish between the cells of a toadstool and those of a human being.
But when all this has been explained, we have still left one great question unanswered. How is the protoplasm made? Is there any connexion of development to be traced whereby life can be shewn to have arisen from inorganic matter? Protoplasm, under a.n.a.lysis, is found to consist of some of the commonest elements on the earth"s surface, such as carbon, hydrogen, oxygen, nitrogen, and phosphorus. Apart from its very complicated structure, its contents are not hard to provide. And we know that there was a time when it must of necessity have been formed out of that which was not living, {78} for there was a time when our globe was in a state of incandescent heat in which no life that we know could possibly have existed. More than this we cannot say. Sir William Thomson, as President of the British a.s.sociation in 1871, suggested that a germ of life might have been wafted to our world on a meteorite; but to say that is obviously only to banish the problem to a greater distance.[1]
Huxley had, in 1868, invented the name "Bathybius" to describe the deep-sea slime which he held to be the progenitor of life on the planet. But later on he frankly confessed that his suggestion was fruitless, acknowledging that the present state of our knowledge furnishes us with no link between the living and the not-living.
And so the problem remains. Sir Edward Schafer, indeed, has laid it down that "we are compelled to believe that living matter must have owed its origin to causes similar in character to those which have been instrumental in producing all other forms of matter in the universe; in other words, to {79} a process of gradual evolution,"[2] but he can throw no further light on the process and its stages.
Sir Oliver Lodge is but speaking the admitted truth when he says that "Science, in chagrin, has to confess that hitherto in this direction it has failed. It has not yet witnessed the origin of the smallest trace of life from dead matter."[3]
No doubt there are many who are hopeful that it may yet be possible to discover a way by which a cell, discharging all the essential functions of life, can be constructed out of inorganic material; or, at least, that it may be possible to frame an intelligible hypothesis as to how this might have been done under conditions which long ago may have been more favourable than our own. But, on the other hand, there are not a few who have quite deliberately abandoned any expectation of the kind.
This was made plain by some of the expressions of adverse opinion which were elicited by Sir Edward Schafer"s address. Of these the following may be given as specimens: "The more they saw of the lower forms of life, the more remote seemed to become the possibility of conceiving how life arose."[4]
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"He could not imagine anything happening in the laboratory, according to our present knowledge, which would bring us any nearer to life."[5]
"Living protoplasm has never been chemically produced. The a.s.sertion that life is due to chemical and mechanical processes alone is quite unjustified. Neither the probability of such an origin, nor even its possibility, has been supported by anything which can be termed scientific fact or logical reasoning."[6]
"The phenomena of life are of a character wholly different from those which are presented by matter viewed under any other aspect, mechanical, electrical, chemical, or what not. It is beside the question to point to the fact that in Nature "new elements are making their appearance and old elements disappearing," for though we may speculate as to the manner of formation of uranium and thorium, and though the production of radio-active matters in Nature at the present time and always seems to be a well-established fact, such phenomena have not even an a.n.a.logy with those of a living being, however humble."[7]
It cannot be surprising that those who believe {81} the door to be shut, so to speak, in the direction of any theory of development through mechanical and chemical agencies alone, should look elsewhere for the solution of a problem which science is bound to do its very utmost to solve. This is what, as a matter of fact, is happening; and it is of the very deepest interest to observe the nature of the suggested explanation. It is no other than a revived form of the ancient doctrine of a "vital force," which we had imagined to have been finally discarded. There is this difference, however, and it is all-important. The force is not, as formerly supposed, some unique kind of energy; is not, indeed, energy at all. But we shall do best to state the new doctrine in the words of its leading exponents.
Professor Anton Kerner, one of the most distinguished German writers on Botany, in his _Natural History of Plants_, speaking of the chemical explanation, says: "It does not explain the purposeful sequence of different operations in the same protoplasm without any change in the external stimuli; the thorough use made of external advantages; the resistance to injurious influences; the avoidance or encompa.s.sing of insuperable obstacles; the punctuality with which all the functions are performed; the periodicity which occurs with the greatest regularity under constant conditions of environment; {82} nor, above all, the fact that the power of discharging all the operations requisite for growth, nutrition, renovation and multiplication is liable to be lost."
And then he gives his opinion thus: "I do not hesitate again to designate as vital force this natural agency, not to be identified with any other, whose immediate instrument is the protoplasm, and whose peculiar effects we call life."
Sir Oliver Lodge is, perhaps, the most uncompromising advocate of the newer vitalism in England. The following striking quotations will set forth his views:
Life, he maintains, is no more a function of matter "than the wind is a function of the leaves which dance under its influence."[8]
"If it were true that vital energy turned into, or was anyhow convertible into, inorganic energy, if it were true that a dead body had more inorganic energy than a live one, if it were true that "these inorganic energies" always, or ever, "reappear on the dissolution of life," then, undoubtedly, _cadit quaestio_, life would immediately be proved to be a form of energy, and would enter into the scheme of physics. But, inasmuch as all this is untrue--the direct contrary of the truth--I maintain that life is not a form of {83} energy, that it is not included in our present physical categories, that its explanation is still to seek."
"It appears to me to belong to a separate order of existence, which interacts with this material frame of things, and, while there, exerts guidance and control on the energy which already exists."[9]
"Life does not add to the stock of any human form of energy, nor does death affect the sum of energy in any known way."[10]
"Life can generate no trace of energy, it can only guide its trans.m.u.tations."[11]
"My contention then is--and in this contention I am practically speaking for my brother physicists--that whereas life or mind can neither generate energy nor directly exert force, yet it can cause matter to exercise force on matter, and so can exercise guidance and control; it can so prepare any scene of activity, by arranging the position of existing material, and timing the liberation of existing energy, as to produce results concordant with an idea or scheme or intention; it can, in short, "aim" and "fire.""[12]
"It is impossible to explain all this fully by the laws of mechanics alone."[13]
"On a stagnant and inactive world life would be {84} powerless: it could only make dry bones stir in such a world if it were itself a form of energy. It is only potent where inorganic energy is mechanically "available"--to use Lord Kelvin"s term--that is to say, is either potentially or actually in process of transfer and transformation. In other words, life can generate no trace of energy, it can only guide its transformation."[14]
"Life possesses the power of vitalising the complex material aggregates which exist on this planet, and of utilising their energies for a time to display itself amid terrestrial surroundings; and then it seems to disappear or evaporate whence it came."[15]
To these voices from Germany or England we can add that of M. Bergson from France. In many respects, as he says, he is at one with Sir Oliver Lodge. If he goes beyond him, it is mainly in these ways. He emphasises the element of Freedom, the power of choice as shewn by every living thing. It appears, he says, "from the top to the bottom of the animal scale," "although the lower we go, the more vaguely it is seen." "In very truth, I believe no living organism is absolutely without the faculty of performing actions and moving spontaneously; for we see that even in the vegetable world, where {85} the organism is for the most part fixed to the ground, the faculty of motion is asleep rather than absent altogether. Sometimes it wakes up, just when it is likely to be useful."
And this is not all. What is specially characteristic of M. Bergson is the insistence that this power of choice is an evidence of Consciousness. "Life," he declares, "is nothing but consciousness using matter for its purposes." "There is behind life an impulse, an immense impulse to climb higher and higher, to run greater and greater risks in order to arrive at greater and greater efficiency."
"Obviously there is a vital impulse."[16]
"Life appears in its entirety as an immense wave which, starting from a centre, speeds outwards, and which on almost the whole of its circ.u.mference is stopped"--that is, as he explains, by matter--"and converted into oscillation; at one point the obstacle has been forced, the impulsion has poured freely. It is this freedom that the human form registers. Everywhere but in man consciousness has had to come to a stand; in man alone it has kept on its way. Man continues the vital movement indefinitely, although he does not draw along with him all that life carries in itself. On other {86} lines of evolution there have travelled other tendencies which life implied"--the reference is more especially to powers of instinct as distinguished from those of intelligence--"and of which, since everything interpenetrates, man has doubtless kept something, but of which he has kept only a little."[17]
Perhaps the most astonishing thing about M. Bergson"s philosophy is his unreadiness to allow that the consciousness, which he says is everywhere at work, has any deliberate purpose in its working. Mr.
Balfour has called attention to the unsatisfactoriness of what he described as "too hesitating and uncertain a treatment."[18]
But, in spite of so serious an omission, we may be glad to believe, with our acute statesman-critic, that "there is permanent value in his theories." If they indicate at all the direction in which scientific thinking is to move, we shall soon have travelled a very long distance from the days in which it was imagined that all vital phenomena might be accounted for on merely materialistic and mechanical lines.
[1] "To this "meteorite" theory the apparently fatal objection was raised that it would take some sixty million years for a meteorite to travel from the nearest stellar system to our earth, and it is inconceivable that any kind of life could be maintained during such a period."--Schafer.
[2] Presidential Address to British a.s.sociation, at Edinburgh (1912).
[3] _Man and the Universe_, p. 24.
[4] Prof. Wager.
[5] Dr. J. S. Haldane.
[6] Dr. A. R. Wallace. Article in _Everyman_, October 18th, 1912.
[7] Sir William Tilden. Letter to _The Times_, September 9th,1912.
[8] _Life and Matter_, p. 106.
[9] Pp. 132, f.
[10] P. 158.