The Future of Mankind
by Pierre Teilhard de Chardin

Chapter 13: The Human Rebound of Evolution and its Consequences

1. Introduction. The Rebounding of Evolution

A year ago I argued in this journal that, observed in a certain aspect (the truly scientific aspect, in my view), the human social phenomenon affords evidence that the evolution of Life on earth, far from having come to a stop, is on the contrary now entering a new phase.(Cf. chapter x, The Formation of the Noosphere. Revue des Questions Scientifiques, January 1947.)

I maintained that, contrary to the commonly expressed or tacitly accepted view, the era of active evolution did not end with the appearance of the human zoological type: for by virtue of his acquirement of the gift of individual reflection Man displays the extraordinary quality of being able to totalize himself collectively upon himself, thus extending on a planetary scale the fundamental vital process which causes matter, under Certain conditions, to organize itself in elements which are ever more complex physically, and psychologically ever more centrated. Thus (provided always that we accept the organic nature of the social phenomenon) we see being woven around us, beyond any unity hitherto acknowledged or even foreseen by biology, the network and consciousness of a Noosphere(It should be noted here that by its nature as a centrated, ‘reflective’ collectivity, the Noosphere, while occupying the same spatial dimensions as the Biosphere, differs from it profoundly in its structure and quality of vital completion. Whereas the Biosphere in its essence is complexity linked but divergent and diffused, the Noosphere combines in itself the properties of a planetary zone (or sphere) and those of a sort of higher individuality endowed with something in the nature of a super-consciousness.)

Following upon this I argued that biological evolution is not only being extended beneath our gaze through the development of the human social group, but that it gives the impression of rebounding upon itself. Although in the pre-human stages of evolution the gradual growth of consciousness in animals (see Section 2, below) does not appear to have had any appreciable effect on the course or speed of their zoological evolution, from the time of Man the evolutionary mechanism undergoes a radical change. For Man, by the act of ‘noospherically’ concentrating himself upon himself, not only becomes reflectively aware of the ontological current on which he is borne, but also gains control of certain of the springs of energy which dictate this advance: above all, collective springs, in so far as he consciously realizes the value, biological efficiency and creative nature of social organization; but also individual springs m as much as, through the collective work of science, he feels himself to be on the verge of acquiring the power of physicochemical control of the operations of heredity and morphogenesis in the depths of his own being. So we may say that since by a sort of chain-reaction consciousness, itself borne of complexity, finds itself in a position to bring about ‘artificially’ a further increase of complexity in its material dwelling (thus engendering or liberating a further growth of reflective consciousness, and so on . . .) the terrestrial evolution of Life, following its main axis of hominization, is not only completely altering the scale of its creations but is also entering an ‘explosive’ phase of an entirely new kind.

To me this appears the most satisfactory interpretation of the present state of Life on the surface of the earth; despite a regrettable recrudescence of racialism and nationalism which, impressive though it may be, and disastrous in its effect upon our private post-war lives, seems to have no scientific importance in the overall process: for the reason that any human tendency to fragmentation, regardless of its extent and origin, is clearly of an order of magnitude inferior to the planetary forces (geographic, demographic, economic and psychic) whose constantly and naturally growing pressure must sooner or later compel us willy-nilly to unite in some form of human whole organized on the basis of human solidarity.(See below, under ‘Conclusion’, remarks on ‘the critical lines of attraction’ between human particles.)

I shall not here attempt the perilous and fruitless task of prognosticating the stages, or the probable duration, or the terminal modalities of this inevitable unification of the human species. I will only recall that, by virtue of its convergent nature, hominization is scarcely conceivable (seen from the point at which we find ourselves) except as terminating, whatever road it follows, in a point of collective reflection where Mankind, having achieved within and around itself, technically and intellectually, the greatest possible coherence, will find itself raised to a higher critical point -- one of instability, tension, inter-penetration and metamorphosis -- coinciding, it would seem, with what for us are the phenomenal limits of the world.

But I wish, on the other hand, to insist upon certain consequences, of an immediately practical kind, ensuing from what I have called the ‘reflective rebound’ of evolution upon itself; consequences which all converge in a single generalized phenomenon -- namely, an irresistible functional incorporation of the psychic within the physico-chemical which recurs in the process of evolution from the time of the coming of Man.

Let me explain.

2. Emergence of the Finality

From the early beginnings of biological evolutionary theory, in the nineteenth century, two trends of thought have prevailed in scientific circles, developing side by side without mingling to any appreciable extent. No one doubts any longer that the world of living forms is the outcome of increasingly complex associations between the material corpuscles of which the universe is composed.(cf. Les Ètudes, May 1946 ) But how are we to envisage the generative mechanism of this ‘complexification’? It is very certain that matter on Earth is involved in a process which causes it to arrange itself starting with relatively simple elements, in ever larger and more complex units. But how are we to account for the origin and growth of this process of arrangement? Does it proceed from within, being conceived and ensued by psychic forces analogous to our human power of invention? Or does it simply come from outside, through the automatic selection of the more stable (or progressive) groupings among the immense number of combinations fortuitously and incessantly produced in Nature? It is curious to note how since the time of Lamarck and Darwin these two theories, while deepening in their respective ways, have become more sharply opposed. And with varying fortunes. Neo-Darwinism at present holds the ascendancy in the eyes of biologists, partly owing to a clearer and more statistically substantiated definition of ‘the fittest’, but principally because of the immense part, now recognized by modern genetics, played by the ‘action of large numbers’ in the formation of species.

It is to this conflict of opinion -- so apparently unyielding that one is inclined to wonder if it has not escaped from the realm of fact to become a simple clash of metaphysical or temperamental preferences -- that the hypothesis of a human rebounding of Evolution does, I believe, if Science will accept it, bring a solution and a satisfactory issue. And in the following manner.

That Man displays powers of invention in the creative use of his reflective faculties, that is to say, acts in accordance with an inner sense of purpose, is so apparent that no one has ever thought of denying it. But this fact remained suspended in a void, and without precise significance, while Man and his activities appeared to be isolated and as it were unattached in the bosom of Nature. The whole situation changes if, for reasons solidly bound up with the general structure of the Universe, we regard the process of hominization, with all its accoutrement of social and ‘artificial’ arrangements, as a prolongation and organic continuance of the grand cosmic phenomenon of the vitalization of matter. It then appears that if the neo-Darwinians are right (as they possibly and indeed probably are) in claiming that in the pre-human zones of Life there is nothing but the play of chance selection to be detected in the advance of the organized world, from the time of Man, on the contrary, it is the neo-Lamarckians who have the better of the argument, since at this level the forces of internal arrangement begin to be clearly manifest in the process of evolution. Which amounts to saying that biological purposiveness (as with so many other physical parameters of the universe) is not everywhere apparent in the living world, but that it only shows itself above a certain level -- its appearance coinciding, not with any particular stage between the Immense and the Infinitesimal but (as in the case of Life itself) with the attainment of a certain value in the ‘axis of complexities’. Below this critical point everything happens (perhaps?) as though the rise of Life were automatic. But above it the forces of free choice and inner direction come to light, and from this moment it is they that tend to take charge.

The point I wish to make is this. In the present state of hominization, as we see it in progress today, the statistical influence of chance and the part played by natural selection continue to be enormous. Compared with this immense passive field (the Darwinian) it may seem that the (Lamarckian) ground gained by our inventive efforts amounts to very little. But let us make no mistake about it. However slight the growth may be, however small the seed, it is precisely here that the power of renewal and rebounding of the living world is concentrated. Born under the appearance and the sign of Chance, it is only though reflective purposiveness, slowly acquired, that Life can henceforth hope to raise itself yet higher, by auto-evolution, in the twofold direction of greater complexity and fuller consciousness. Indeed, from now on all the hopes and future of the Universe are dependent on the propitious and stubborn working of this scarcely-born power of internal ‘self-arrangement.’

And this means, if we are not to regard the world as having become suddenly meaningless and contradictory, that we are entitled to attribute the value of experimental and physical reality to everything, within us and around us, which shows itself to be a necessary condition for the preservation and heightening in Man of his powers of invention and purposive thinking.

3. The Control and Preservation of Purposive Thinking

After a short period of untroubled proprietorship every new source of energy, as we know by experience, gives rise to two related problems, that of the limitations to be imposed on it and that of its preservation. The new force must not be allowed to get out of hand or to exhaust itself. The same applies (although we have thought less about it) to the source of energy abruptly released by Nature through Man which I have called the ‘force of purposive thinking.’ In its early forms human inventive power, as we still see in children, may be likened to a game. In those first manifestations of the power of reflective arrangement, everything appears simple, harmless and even beneficent, giving no hint of a moment to come when we can no longer go on playing. But as the phenomenon spreads and develops within a Mankind in process of becoming adult, what once looked like a game is suddenly found to be deadly earnest. The ‘sorcerer’s apprentice’ by dint of fumbling has laid hands on forces of such power that he begins to be afraid of causing some disaster in Nature. And on the other hand, finding that by his discoveries he has acquired certain keys to the mastery of the world, he begins to realize that if he is to be equal to the situation he is bound, in his role of ‘quasi-demiurge’, to establish principles and a faith regarding the future and the value of the task that is henceforth imposed upon him.

Two roads, as I shall seek to show, by which certain energies and certain radiations, moral and mystical in their nature, inevitably make their appearance at the heart of the biological flux of evolution.

a The Moral Ordering of Invention. By ‘invention’ I mean to designate, in the widest sense of the word, everything in human activity which in one way or another contributes to the organico-social construction of the Noosphere and the development within it of new powers for the arrangement of Matter. From the ‘materialist’ point of view the progress of invention in this sense will be entirely governed by the pressure of external necessities, primarily economic. But it has become plain (in particular since the last war) that however urgent may be the planetary pressures driving us to unite, they cannot operate effectively in the long run except under certain psychic conditions, some of which arise out of the human neo-mystique to be discussed in the next paragraph, but the rest of which merely recall and re-express, with a precise biological foundation, the broad lines of the empirical and traditional Ethics which has been evolved in some ten millennia of civilization. It is enough for me to cite the twofold respect for things and for personality in the individual. Clearly whatever we may seek to build will crumble and turn to dust if the workmen are without conscience and professional integrity.(In this connection it is interesting to note the extent to which the lie (a relatively minor evil in more restricted groups) is fast becoming an inhibiting major vice in large social organisms, so that one might say that [like hatred -- and the taedium vitae] it tends to constitute a major obstacle to the formation of a Noosphere.) And it is even more abundantly clear that the greater our power of manipulating inert and living matter, the greater proportionately must be our anxiety not to falsify or outrage any part of the reflective conscience that surrounds us. Within a short space of time, owing to the acceleration of social and scientific developments, this twofold necessity has become so clearly urgent that to refer to it is to utter a commonplace. In recent years voices of alarm have been raised in many quarters pointing to the fast-growing gulf between technical and moral progress in the world today. The perils of the situation are plain to everyone. But do we yet fully recognize its deep significance?

Many people, I am convinced, still regard the higher morality which they look for and advocate as no more than a sort of compensation or external counter-balance, to be adroitly applied to the human machine from outside in order to off-set the overflow of Matter within it. But to me the phenomenon seems to go far deeper and to have far wider implications. The ethical principles which hitherto we have regarded as an appendage, superimposed more or less by our own free will upon the laws of biology, are now showing themselves -- not metaphorically but literally -- to be a condition of survival for the human race. In other words Evolution, in rebounding reflectively upon itself, acquires morality for the purpose of its further advance. In yet other terms, and whatever anyone may say, above a certain level, technical progress necessarily and functionally adds moral progress to itself. All this is surely proof that the two events are interdependent. In fact, the pursuit of human knowledge cannot be carried in concrete terms beyond a certain stage without this power of reflective arrangement becoming automatically charged with internal obligations which curb and direct it; while at the same time, as we shall see, it engenders around itself an entirely new atmosphere of spiritual needs.

b The Spiritual Nourishment of Human Endeavor. It is surprising to note, among the increasingly numerous theorists who, under the pressure of events, are beginning to speculate on the future of the human phenomenon, a sort of tacit agreement whereby vital energy is treated as though it were a constant, both in quality and quantity, like solar radiation or the force of gravity. This postulate of invariability seems at first sight to be admissible in the ‘Darwinian’ zones of Life, where the instinct of self-preservation predominates (this seeming by its nature to be more or less constant among organized beings), but it certainly loses all value in the ‘Lamarckian’ or human zone, where biological evolution, from being passive, becomes active in the pursuit of its purpose. As we know very well in ourselves, and as every leader of men has discovered, human creative energy, according to the degree of temperature generated within it (on a scale, that is to say, between enthusiasm and revulsion) can in a matter of instants leap ‘any distance short of infinity.’

If, therefore, we accept the idea of a reflective rebounding of evolution, it is not enough to reckon the future of the world in terms of reserves of mechanical energy and food supplies, or the probable longevity of the earth. As I said long ago,’ the evolutionary vigor of Mankind can wither away although it be surrounded by mountains of coal, oceans of petroleum and limitless stocks of corn; it can do so as surely as in a desert of ice, if Man should lose his impulse, or worse, develop a distaste for ever-increased growth ‘in complexity and consciousness’. With all respect to the materialist school, which still refuses to examine human biology, it is undeniable that in Man the external drive of Life tends to be transformed and turn inward to become an ardor for Life. Try to get productive work out of a workman, an engineer or a scientist who is ‘browned off’! So in the first place, if Evolution is to continue, it is this impetus which must be maintained in the heart of Man and encouraged to grow at all costs. Failing that upward current, almost nothing will move; whereas with it, everything will happen almost of its own accord in the higher zones, those that are truly progressive, of invention and discovery. But how are we to tap this deep, primordial well?

If the problem of sustaining this human impetus does not trouble the theorists I have referred to, it is, I suppose, because they assume that cases of revulsion will be as exceptional in the future as they have been in the past -- that a sufficient degree of physical health or euphoria will maintain vital pressure at a positive level, moderate but adequate, within the human mass. But is not this to beg the whole question? Not only have powers of reflection and invention been added to Life through hominization, but so has the formidable endowment of criticism. However exuberant our vitality, however rich and sanguine our temperament, it is already becoming impossible, and must inevitably become more so, for us to give ourselves wholly to any creative undertaking if we cannot justify it in rational terms. That is why if Man at this moment finds himself faced with the burden not merely of submitting to the evolutionary process but of consciously furthering it, we may be sure that he will seek, and rightly, to avoid the responsibility and pangs which this entails if the objective does not seem to be worth the effort. Which amounts to saying that the Universe, of psychic or psychological necessity (here they come to the same thing) must possess properties fulfilling the functional needs of reflective action. Otherwise apathy and even disgust will pervade the human mass, neutralizing or reversing every vigorous impulse at the heart of Life.

What and how many are these basic properties, these sine qua non conditions, which we are bound to postulate and presume to be incorporated in the structure of the surrounding world if Evolution, henceforth hominized, is to continue?

In our present state (or more exactly, stage) of psychic awareness it seems to me that they can be brought down to two, very closely related.

The first, as I have argued at length in my chapter on the Noosphere, is that in one way or another Consciousness, the flowering of Complexity, must survive the ultimate dissolution from which nothing can save the corporeal and planetary stem which bears it. From the moment when Evolution begins to think itself it can no longer live with or further itself except by knowing itself to be irreversible -- that is to say, immortal. For what point can there be in living with eyes fixed constantly and laboriously upon the future, if this future, even though it take the form of a Noosphere, must finally become a zero? Better surely to give up and die at once. In terms of this Absolute it is sacrifice, not egotism, that becomes odious and absurd. Irreversibility, then, is the first condition.

The second condition, no more than an amplification of the first, is that the irreversibility, thus revealed and accepted, must apply not to any one part, but to all that is deepest, most precious and most incommunicable in our consciousness. So that the process of vitalization in which we are engaged may be defined at its upper limit (whether we envisage the system as a whole or the destiny of each separate element within it) in terms of ‘ultra-personalization’. The necessity of this must be stressed, since the degree of personalization (or ‘centration’, which comes to the same thing) of a cosmic element being finally the sole parameter by which we can measure its absolute biological value, a world presumed to be heading towards the Impersonal (the word being interpreted in its normal sense of ‘infra-personal’) becomes both unthinkable and unlivable.

An irreversible rise towards the personal: unless it satisfies some Whole comprising these two conjoined attributes, the Universe (psycho-analytically dosed, if I may put it that way) can only become stifling for all reflective activity, that is to say, radically unsuited to any rebound of Evolution. But we are agreed that such a rebound is preparing and indeed has already begun. So we must conclude, unless we favor the idea of a world destined to miscarry through a fault in its construction, that evolutionary irreversibility and personalization (despite their implied anticipation of the future) are realities not of a metaphysical but of a physical order, in the sense that, like the dimensions of Time and Space, they represent general conditions to which the totality of our proceedings must conform.

Failing these conditions, as I have said, everything at the level of Man will cease to move. On the other hand it seems to me that, provided they are fulfilled, nothing can seriously interfere with our natural taste, our impulse, that is to say, towards invention and research. The world will have become habitable for Thought. But is it enough for the world as we are now picturing it to be simply livable, capable, all things considered, of fostering some degree of taste for life? Must it not rather be wholly delectable, if it is to be wholly consistent with itself?

Strange though it may seem, we are here confronted, if we seek to define our Universe in relation to other imaginable kinds of universe, with the necessity and importance of determining what may be called its ‘coefficient of activation’, that is to say, the degree in which it possesses the quality of stimulating the centers of reflective activity contained within it. Theoretically, in virtue of what I have said, a whole series of activations (provided they are positive) is conceivable, each in itself sufficing to create a livable world. But in practice -- does not some sixth sense warn us of this ? -- one value alone is admissible in the experienced reality of action, one alone can truly satisfy us: namely, the greatest of all, in relation to what we are. I do not propose to embark upon any analysis or defense of the very particular kind of optimism which does not for a moment claim that we are living in the best of all possible worlds, but only (a quite different matter!) the most ‘activating’. Let me simply observe that here perhaps we have a basis for prognosticating, in the broadest outline, the religious evolution of the world of tomorrow. From the strictly ‘noodynamic’(‘Noodynamic’: the dynamic of spiritual energy, dynamic of the Spirit. I have ventured to use this neologism because it is clear, expressive and convenient; also because it affirms the necessity for incorporating human psychism, Thought, in a true ‘physics’ of the World.) viewpoint which I have adopted, it may be said that the historic rivalry of mysticisms and creeds, each striving to conquer the earth, represents nothing but a prolonged groping of the human soul m search of a conception of the world in which it will feel itself to be more sensitized, more free and active. This surely means that the faith which finally triumphs must be the one which shows itself to be more capable than any other of inspiring Man to action. And it is here, irrespective of all philosophical or theological considerations, that Christianity decisively takes the lead with its extraordinary power of immortalizing and personalizing in Christ, to the extent of making it lovable, the time-space totality of Evolution.

4. Conclusion. Something New under the Sun

In short, as I said at the beginning, the terrestrial evolution of Life, if it is really to continue as hominization extended to the scale of the Noosphere, cannot rebound in a new spring forward without acquiring a morality, and, to the extent that it needs a ‘faith’, without becoming ‘mysticised’. Which amounts to saying that the complexification of Matter, at the point it has now reached in the human social organism, is physically incapable of advancing further if the Mind does not play a part, not only with its capacity for technical organization, but with its purposive and affective powers of arrangement and inner tension. Which again amounts to saying that from the time of Man (above all, modern Man) the factor consciousness, which for a long time perhaps represented no more than a secondary and accessory effect in Nature, a simple superstructure of the factor complexity, is finally becoming individualized in the form of an autonomous spiritual principle. For its reflective and inventive forward spring it is in some sort necessary that Life, duplicating its evolutionary motive center, should henceforth be sustained by two centers of action, separate and conjoined, one of consciousness and the other of complexity. And herein, if I am right, we may find a bridge of an experimental kind flung across a gap which has hitherto been held to be scientifically unbridgeable. In hominized evolution the Physical and the Psychic, the Without and the Within, Matter and Consciousness, are all found to be functionally linked in one tangible process. Setting aside all metaphysics, the two terms in each of these pairs are articulated in a quasi- measurable fashion one with the other; with the twofold result not only of at last affording us a unified concept of the Universe, but also of breaking down the two barriers behind which Man was coming to believe himself to be for ever imprisoned -- the magic circle of phenomenalism and the infernal circle of egocentrism.

Gone, first of all, the magic circle of phenomenalism, which, we have been assured, must inexorably restrict our gaze to a limited horizon beyond which lies not merely the unknown but the absolutely unknowable. How much has been said even recently(‘It is perhaps inevitable that, having reached the limit beyond which the sure basis of experience fails us, the human spirit, in its impotence, can do no more than revolve in the magic circle of traditional interpretations.’ (Betti, Director of the Chemical Institute of Bologna.) ‘When it comes to those questions on the border-line of the unknowable, all the accumulated knowledge of twenty -- five centuries has done no more than feed the argument, without advancing us a single step towards the solution.’ (Tannery. Pour la Science Hellène; quoted by J. Benda in La Tradition de l’Existentialisme.) about our powerlessness to penetrate in this sense beyond the primitive vision shared by the earliest human minds; that is to say, the impossibility of our advancing a step towards the direct or indirect perception of all that is hidden behind the veil of tangible experience! But it is just this supposedly impenetrable envelope of pure ‘phenomenon’ which the rebounding thrust of human evolution pierces, at least at one point, since by its nature it is irreversible. This does not mean that we can see what lies beyond and behind that trans-phenomenal zone of which we now have an inkling, any more than, having discerned the shape of the earth, we can foresee the landscape lying beyond the horizon. But at least we know that something exists beyond the circle which restricts our view, something into which we shall eventually emerge. It is enough to ensure that we no longer feel imprisoned.

Gone, too, (at least virtually and in aspiration), is the infernal circle of egocentrism, meaning the isolation, in some sort ontological, which prohibits our escape from self to share the point of view even of those we love best: as though the Universe were composed of as many fragmentary universes, repelling each other, as the sum total of the centers of consciousness which it embraces. Who can measure the long chain of harmful, closely interlinked effects which this elemental separatism automatically creates and fosters, by an effect of mass and resonance, within the process of totalization now taking place in Mankind? The iron laws binding economic factors, the irrepressible recurrence of nationalisms, the apparent inevitability of war, the insoluble Hegelian conflicts ‘of master and slave’; what are these supposedly unalterable necessities of the human condition, except, finally, the diverse expression and outcome of exteriority and a mutual antagonism between the individual seeds of thought which we are? . . . Here again let us throw back our heads and breathe freely! For if it be true that the tide of evolutionary totalization sweeping us along requires, for its viability, not only that we must progress towards some form of irreversible unity, but also that this progress must be in the personal sphere, is not this a positive reason for believing that sooner or later something must happen in the world whereby certain basic conditions of the human phenomenon will undergo modification? If our ‘person’ is not to be lost in the vast plurality of Mankind within which it is gradually, and of inescapable physical necessity, becoming integrated; if totalization is to set us free instead of simply mechanizing us; then we must look for and allow for a change of regime. We must assume that under the rapidly mounting pressures forcing them upon one another the human molecules will ultimately succeed in finding their way through the critical barrier of mutual repulsion to enter the inner zone of attraction(This is an old idea which I advanced nearly twenty years ago in an unpublished essay entitled, The Spirit of Earth.)

From that point on we shall be entering a new world of relationships where the hitherto impossible may become simple, being enacted in other dimensions and another environment.

If such a vista still seems to us fantastic, it is simply that we lack imagination. But scientific reason is there to sustain and guide us. Some hundreds of thousands of years ago, upon the first emergence of reflective consciousness, the Universe was surely and beyond question transformed in the very laws of its internal development. Why, then, should we suppose that nothing new will appear under the sun of tomorrow, when the rebounding of Evolution is in full flood?

To sum up.

If social totalization and scientific technology are regarded as they should be, as constituting a direct prolongation, in a human context, of the grand process of the vitalization of Matter, it follows that, from the coming of Man, biological evolution not only rebounds (on a new scale and with new resources) but that it rebounds reflectively upon itself The Darwinian era of survival by Natural Selection (the vital thrust) is thus succeeded by a Lamarckian era of Super-Life brought about by calculated invention (the vital impulse). In Man evolution is interiorized and made purposeful; and at the same time, in the degree in which the strivings of human inventiveness need to be controlled in their operation and sustained in their energies, it imposes upon itself a moral order and ‘mysticizes’ itself. In abstracto or in individuo, technical achievement and moral virtue, science and faith (faith in the future) may seem to be things that are not only separate but even opposed to one another. But in the concrete reality of Total Evolution, and beyond a certain degree of complexity of Consciousness, each of necessity requires the other, because Matter, once hominized, can positively not continue the super-arrangement of itself upon itself except in a specific psychic atmosphere.

Thus a precise functional interlocking of physical and spiritual energy may be discerned. And thus is revealed the necessity for the Universe to present itself to our experience as an irreversible medium of personalization, if the human rebounding of Evolution is not to be stifled at birth.

Saint-Germain-en-Laye, 23 September, 1947. Revue des Questions Scientifiques. 20 April i948.