Part II. On the Possible Bases of a Universal Human Creed
Chapter 6: Life and the Planets
I. Living Planets in the Universe
2. In terms of Complexity; or the Planets as vital centers of the Universe
return us to primal matter. We strut for a tiny moment upon a tiny stage, well knowing that all our aspirations are doomed to ultimate failure and that everything we have achieved will perish with our race, leaving the
another, for the purpose of classifying the objects around us?
I will cite two advantages, although it means somewhat anticipating the latter parts of this lecture.
First, in the multitude of things comprising the world, an examination of their degree of complexity enables us to distinguish and separate those which may be called ‘true natural units’, the ones that really matter, from the accidental pseudo-units, which are unimportant. The atom, the molecule, the cell and the living being are real units because they are both formed and centrated, whereas a drop of water, a heap of sand, the Earth, the Sun, the stars in general, whatever the multiplicity or
elaborateness of their structure, seem to possess no organization, no
‘centricity’. However imposing their extent they are false units, aggregates arranged more or less in order of density.
Secondly, the coefficient of complexity further enables us to establish, among the natural units which it has helped us to ‘identify’ and isolate, a system of classification that is no less natural and universal. Let us try to depict this classification in schematic form, as it might be drawn on a blackboard.
At the very bottom of the board we have the 92 simple chemical elements (from hydrogen to uranium) formed by groups of atomic nuclei together with their electrons.
Above these come the molecules composed of groups of atoms. These molecules, in the case of the carbon compounds, may become
enormous. In the albuminoids (or proteins) there may be thousands of associated atoms: the molecular weight of hemoglobin is 68,000.
Above these again come the mysterious viruses, strange bodies
producing a variety of maladies in animals and plants, concerning which we do not yet know if they are monstrous chemical molecules or living infra-bacteria. Their molecular weight runs into millions.
Higher still we come to the lowest cells. I do not know if any attempt has yet been made to ascertain the atomic content of these (it must amount to billions) but they are undoubtedly groups of proteins.
And finally we reach the world of higher living forms, each composed
of groups of cells. To take a very simple instance, that of the plant duckweed; its content is estimated to be 4 X 1020 atoms.
For the present we will disregard an even higher category which may conceivably have its place at the head of the list -- that formed by the grouping, not merely of cells, but of metazoa synthetically associated in such a manner as to comprise, when taken together, a single, living super-organism. We shall come back to this.
This scheme of classification, based essentially on the intimate structure of objects, is undeniably natural in principle. But it can also be seen to possess a double and extreme significance.
It is significant, in the first place, because for the scientist it bridges the long-standing, troublesome and seemingly irreducible gap between biology and physics. The wide distinction which for philosophical reasons we have thought it necessary to draw between life and matter ceases to be valid as a law of recurrence comes to light, in the
phenomenal field, for practical purposes linking these two orders of phenomena. Beyond the millionth atom everything happens as though the material corpuscles stirred and were vitalized; the Universe
organizes itself in a single, grand progression, somewhat untidy no doubt, but on the whole clear in its orientation, ascending from the most rudimentary atom to the highest form of living things.
Secondly it is significant because, arranged according to our scale of complexity, the elements succeed one another in the historical order of their birth. The place in the scale occupied by each corpuscle situates the element chronologically in the genesis of the Universe, that is to say, in Time. It dates it.
Thus the rising scale conforms both to the ascending movement towards higher consciousness and to the unfolding of evolutionary time. Does not this suggest that, by using the degree of complexity as a guide, we may advance very much more surely than by following any other lead as we seek to penetrate to the truth of the world and to assess, in terms of absolute values, the relative importance, the place, of all things?
With this in mind let us look again at the vast sidereal units (galaxies and suns) and this time try to assess their importance not in terms of their immensity or even complexity (since, as I have said, nebulae and stars are no more than aggregates) but in terms of the complexity of the
elements which compose them.
We now see a very different picture; a complete reversal of values and perspective.
Let us look first at what is largest, the galaxies. In their least condensed parts (that is to say, in what they still contain of the vestiges of
primordial chaos), the matter composing them is extremely tenuous;
probably hydrogen, the most primitive substance known to us in the field of distinguishable matter. One nucleus and one electron: the simplest combination imaginable.
Now come down a stage in the scale of the immensities and look at the stars. Here the chemism is more elaborate. Whether in the red giants, the medium yellows or the white dwarfs, we may surmise at the presence in the center of heavy and extremely unstable elements possessing a greater atomic weight than uranium (unless these are simply ‘ordinary matter’ reduced to a physical state of extraordinary compression). At the same time, in the lighter surface-zone enveloping these depths the spectroscope can discern the entire range of our simple elements. In the stars, therefore, if we compare them with the original galaxies, the degree of complexity rises rapidly; but, and this is of major importance, it cannot go beyond a certain stage; that is to say (if we except a number of simple groups perceptible in the incandescent atmosphere of certain stars) it cannot reach the level of the composite bodies, i.e., the large molecules. The fact is that even on the periphery of these prodigious centers of energy the temperature is far too great for any higher combination to possess stability. The stars are essentially laboratories in which Nature, starting with primordial hydrogen,
manufactures atoms. For the operation to go beyond this point we have to imagine two astonishing things:
First, that by a sort of ‘skimming’ process a portion of the stellar substance separates from the rest, deriving entirely from the surface- zone of lighter atoms which are not constantly threatened with radio- active disintegration. The larger molecules can only be constructed of elements possessing almost unlimited stability.
Secondly, that this light and stable ‘cream’ of any given star, having escaped beyond the reach of the tempest of energy blazing at the heart of the parent-body, may yet remain sufficiently close to it to derive a moderate benefit from its radiations: for the large molecules need
energy for their synthesis.
But are not these two providential occurrences (the selection of a suitable ‘dough’ and its treatment in a suitable ‘oven’) precisely what that mysterious body, our father-star, effected in a single operation when, passing close to our Sun, it detached from its surface and scattered over a wide distance the ribbon of matter that became the planets?
You will now see where my argument is tending, or more exactly, where the guide which we have elected to follow, the scale of complexity, is irresistibly leading us. Despite their vastness and
splendor the stars cannot carry the evolution of matter much beyond the atomic series: it is only on the very humble planets, on them alone, that the mysterious ascent of the world into the sphere of high complexity has a chance to take place. However inconsiderable they may be in the history of sidereal bodies, however accidental their coming into
existence, the planets are finally nothing less than the key-points of the Universe. It is through them that the axis of Life now passes; it is upon them that the energies of an Evolution principally concerned with the building of large molecules is now concentrated.
We may well be dismayed by the rarity and improbability of heavenly bodies such as our own. But does not everyday experience teach us that in every order of Nature, and at every level, nothing succeeds except at the cost of prodigious waste and fantastic hazards? A monstrously fragile conjunction of chances normally dictates the birth of the most precious and essential beings. We can only bow before this universal law whereby, so strangely to our minds, the play of large numbers is mingled and confounded with a final purpose. Without being overawed by the Improbable, let us now concentrate our attention on the planet we call Earth. Enveloped in the blue mist of oxygen which its life breathes, it floats at exactly the right distance from the sun to enable the higher chemisms to take place on its surface. We do well to look at it with emotion. Tiny and isolated though it is, it bears clinging to its flanks the destiny and future of the Universe.
II. Man on the Planet Earth: The Most Complex of Molecules