WHAT IS LIFE?

Evening Post, Volume CVIII, Issue 148, 19 December 1929, Page 30

WHAT IS LIFE?

AN UNSOLVED MYSTERY

WHAT SCIENTISTS KNOW

BIOLOGISTS IN A CRISIS

At the recent meeting of the British Association in South Africa there was a special conference on the most important of all subjects, life. We are unable—at least in the present state o£ our knowledge—to answer the question "What is Jife?" nor did the conference attempt anything so ambitious. The debate—which, is summarised in the periodical "Nature" —was no more, because it could be no more, than a kind of groping in darkness after new approaches to the science of biology. For the old approaches are leading us astray, or at least no farther on. There was a time, not very long ago, when it seemed that life could be explained in terms o£ chemistry and physics. It was even supposed that life could be manufactured in the laboratory, and now and again the press would announce that the "secret of life" had been "discovered" and that some biologist had produced a speck of "living matter" in vis crucible. The living organism, writes a correspondent in the "Manchester Guardiau," was looked upon as a sort of machine. But it is not a machine, nor does it remotely resemble a machine. It is not even in any way analogous to a machine. No machine manufactures itself, repairs itself, and reproduces itself. Machines . can be explained in terms of chemistry and physics, but living organisms have never been, and our growing knowledge makes it seem more and more certain that they never will be, explained in these terms. The failure of "mechanism" to explain consciousness, instinct, emotion, and so on seemed to leave a gap that had to be filled. It was filled by a mystic something-or-other, by the "vital principle" which, so to speak, runs the machine. But both "mechanism" and "vitalism," although ap-. parently oppositeg, are not really so. They are both, founded on the Cartesian belief that the living- organism is a kind of machine, the ffnly difference being that the "mechanist" thinks the machine runs itself, whereas the "vitalist" thinks it is run by a sort of transcendental chauffeur. General Smuts was surely right when in his address to the members of the British Association he said that both "mechanism" and "vitalism" should be abandoned. They are approaches that have come to lead astray or nowhere, and new approaches must be found. But how? LIMITS OF OUR KNOWLEDGE. Life is a phenomenon we know of only in organised," individualised entities that are always renewing their own form and structure. They are -more than the sum total of their chemico-physical properties, and the problem of life is more than one of chemistry and physics; it is also a problem of form and structure. It is the problem of the organism in its totality, for without this totality there is—so we are being compelled to believe—no life. That is to say, therf is no such thing as "a living substance," a particular kind of matter that has the property of "being alive." That is why, although living things can be resolved into their constituents, these constituents cannot be remade into living things. We have no knowledge of how life began. We only know of life arising out of life. Nor do we know how it operates. We can, through a good microscope, follow the beautiful, complicated, and yet regular process of cell division. A star appears in the cell, it becomes two stars, they wander to opposite poles of the cell, they stretch out arms towards one another, so that they are interlocked by a kind of spindle. On this spindle portentous things happen, although within dimensions unimaginably small. And then across the spindle's waist a wall is formed, and the cell becomes not two half but two whole cells. There is nothing in the mechanical, physical, or chemical world in the least like this one fundamental process, which is common to elephants, primroses, fantail pigeons, Virginia creepers, and human beings. But although we can see and label certain factors and stages in this process we really know nothing about it. Nor do we know how living creatures, with this fundamental process in common, have acquired their immense diversity. Evolution is a postulate we are bound to accept, for without it. this diversity' would be a chaos—and a chaos it certainly is 'not, for amongst the different kinds of creatures^ that make up this diversity there is kinship, and where there is kinship there is common descent. Descent and change make evolution. But that is about all we know. We do not know what causes evolution. Why should living organisms "evolve" at all, when they are all, the "lowest" with the "highest," equally well^ adapted each kind to its o.ii environment? ' There is as yet no satisfactory answer to this question. BIOLOGISTS HAMPERED. We know a prodigious number of facts about plants and animals. But without theory there can be no true /knowledge. .Perhaps the greatest need of biology is a theoretical approach. "Nature" has just brought to the notice of English readers a marvellous study and exposition of this need by the German biologist Yon Uexkull. Biology has no Newton, no Maxwell nc; Planck, no Einstein. It has no laws, although it has all kinds of fancies, some useful assumptions, and at best some rules (Mendel's "law" is such a rule, and, in its simplicity and precision, perhaps the" biggest single contribution yet made to biological science). The laws of physics are the common theoretical foundation of everprogressing, co-ordinated thought and inquiry. Biology has no such foundation. That is why physical science is team work and biology a hullabaloo. Physicists march from triumph to triumph, while biologists are in a crisis from which as yet no way out is visible. Perhaps the reason is that biology has suffered too much from the domination of chemistry and physics. If life is inexplicable in chemico-physical terms, the attempt must be made to explain it in other terms. Perhaps biology must become something more than another kind of chemistry and physics. Perhaps it has also suffered too much from human selfcentredness. Animals live lives of their own in worlds of their own that are quite different from our lives and our world. We are prone to colour-our contemplation of the animal world by our own prevalent ideas, particularly the idea of progress. But progress is a purely subjective, not an objective reality. Biology sometimes seems to be no science at all—at least compared with physics—but a strange, contradictory mixture of subjective and objective assumption of fancies, and of ill-co-brdinated data. But perhaps the realisation that the living organism is living only in so far as it is a totality and that this totality has its own secrets and its own laws that are quite different from the laws of chemistry and physics, that the! living -world is a world of its own, will give, biology the independence it so much needs, will save it from its present crisis, and will give it a status and an authority equal to. that of chemistry arid physics. "It will then, perhaps, be possible to begin attempting a theoretical answer to the question "What is life?"