“What we do not know today we shall know tomorrow.” This simple statement underlies the conclusion of a scientific paper on the Origin of Life written by the Russian biologist Aleksandr Ivanovich Oparin in 1924. It was the first time that a modern appreciation of the subject had been undertaken, and opened up a new chapter in the understanding of life. It was no accident that as a materialist and dialectician, Oparin approached this subject from an original perspective. This was a bold beginning, at the very dawn of biochemistry and molecular biology, and was backed up independently by the contribution of British biologist JBS Haldane – again a materialist – in 1929. This work produced the Oparin-Haldane hypothesis, on which the subsequent understanding of the origin of life is based was described by Asimov:

In it, the problems of life’s origin for the first time was dealt with in detail from a completely materialistic point of view. Since the Soviet Union is not inhibited by the religious scruples to which the Western nations feel bound, this, perhaps, is not surprising.[6]

Oparin always acknowledged his debt to Engels, and made no secret of his philosophical position:

“This problem [of life’s origins] has however always been the focus of a bitter conflict of ideas between two irreconcilable schools of philosophy – the conflict between idealism and materialism.”

“A completely different prospect opens out before us if we try to approach a solution of the problem dialectically rather than metaphysically, on the basis of a study of the successive changes in matter which preceded the appearance of life and led to its emergence. Matter never remains at rest, it is constantly moving and developing and in this development it changes over from one form of motion to another and yet another, each more complicated and harmonious than the last. Life thus appears as a particular very complicated form of the motion of matter, arising as a new property at a definite stage in the general development of matter.

“As early as the end of the last century Frederick Engels indicated that a study of the history of the development of matter is by far the most hopeful line of approach to a solution of the problem of the origin of life. These ideas of Engels were not, however, reflected to a sufficient extent in the scientific thought of his time.”

Engels was essentially correct when he described life as the mode of motion of proteins. However, today we can add that life is the function of the mutual reactions of nucleic acids and of proteins. As Oparin explained:

“F. Engels, in common with biologists of his time, often used the terms ‘protoplasm’ and ‘albuminous bodies’. The ‘proteins’ of Engels must therefore not be identified with the chemically distinct substances which we have now gradually succeeded in isolating from living things, nor with purified protein preparations composed of mixtures of pure proteins. Nevertheless Engels was considerably in advance of the ideas of his time when, in speaking of proteins, he specially stressed the chemical aspects of the matter and emphasised the significance of proteins in metabolism, that form of the motion of matter which is characteristic of life.”

“It is only now that we have begun to be able to appreciate the value of the remarkable scientific perspicacity of Engels. The advances in protein chemistry now going on enabled us to characterise proteins as individual chemical compounds, as polymers of amino acids having extremely specific structures.”[7]

JD Bernal offers an alternative to Engels’s definition of life as “a partial, continuous, progressive, multiform and conditionally interactive, self-realisation of the potentialities of atomic electron states.”[8]

Although the Oparin-Haldane hypothesis laid the basis for a study of life origins, as a branch of science it is more correct to ascribe it to the revolution in biology in the mid-20th century. Theories concerning the origin of life are largely speculative. There are no traces in the fossil record. We are dealing here with the simplest and most basic life-forms imaginable, transitional forms which were quite unlike the idea of living things we have today, but which nevertheless represented the decisive leap from inorganic to organic matter. Perhaps, as Bernal comments, it is more correct to say the origin not of life, but the origin of the processes of life. Engels explains that the Darwinian revolution

“reduced the gulf between inorganic and organic nature to a minimum but removed one of the most essential difficulties that had previously stood in the way of the theory of descent of organisms. The new conception of nature was complete in its main features; all rigidity was dissolved, all fixity dissipated, all particularity that had been regarded as eternal became transient, the whole of nature shown as moving in eternal flux and cyclical course.”[9]

The scientific discoveries since this was written have served to strengthen this revolutionary doctrine. Oparin drew the conclusion that the original atmosphere of the earth was radically different from that of today. He suggested that instead of oxygen, the character of the atmosphere was reducing rather than oxidising. Oparin proposed that the organic chemicals on which life depends formed spontaneously in such an atmosphere under the influence of ultraviolet radiation from the sun. Similar conclusions were arrived at independently by JBS Haldane:

The Sun was perhaps slightly brighter than now and as there was no oxygen in the atmosphere the chemically active ultraviolet rays from the Sun were not, as they now are, mainly stopped by ozone (a modified form of oxygen) in the upper atmosphere, and oxygen itself lower down. They penetrated to the surface of the land and sea, or at least to the clouds. Now, when ultraviolet acts on a mixture of water, carbon dioxide, and ammonia, a vast variety of organic substances are made, including sugars and apparently some of the materials from which proteins are built up.[10]

In a more generalised form Engels pointed in the right direction fifty years previously: “If, finally, the temperature becomes so far equalised that over a considerable portion of the surface at least it does not exceed the limits within which protein is capable of life, then, if other chemical conditions are favourable, living protoplasm is formed.” He continued,

Thousands of years may have passed before the conditions arose in which the next advance could take place and this formless protein produce the first cell by formation of nucleus and cell membrane. But this first cell also provided the foundation for the morphological development of the whole organic world; the first to develop, as it is permissible to assume from the whole analogy of the palaeontological record, were innumerable species of non-cellular and cellular protista…[11]

Although this process took place over a far longer time-span, this is a generally correct prognosis. Just as Engels’ ideas were ignored at the time by the scientific community, so were those of Oparin and Haldane. Only recently are these theories getting the recognition they deserve. Richard Dickerson writes:

Haldane’s ideas appeared in The Rationalist Annual in 1929, but they elicited almost no reaction. Five years earlier Oparin had published a small monograph proposing rather similar ideas about the origin of life, to equally little effect. Orthodox biochemists were too convinced that Louis Pasteur had disproved spontaneous generation once and for all to consider the origin of life a legitimate scientific question. They failed to appreciate that Haldane and Oparin were proposing something very special: not that life evolves from non-living matter today (the classical theory of spontaneous generation, which was untenable after Pasteur) but rather that life once evolved from non-living matter under the conditions prevailing on the primitive earth and in the absence of competition from other living organisms.[12]

  1. Asimov, I. op. cit., p. 592.

  2. Oparin, A. The Origin of Life on Earth, pp. xii and 230-1.

  3. Bernal, J. The Origin of Life, p. xv.

  4. Engels, F. Dialectics of Nature, p. 13.

  5. Haldane, J. The Rationalist Annual, 1929.

  6. Engels, F. The Dialectics of Nature, p. 16.

  7. Scientific American, 239 [1978].