the air is extracted from an alveolus, a cone of attraction is seen to fonn, like those about the ceutrosomes which result in the division of the nucleus.* Even the external motions of a imicellular organism — of an amoeba, at any rate — are sometimes explained mechanically. The dis- placements of an amoeba in a drop of water would be comparable to the motion to and fro of a gram of dust in a draughty room. Its mass is all the time absorbing certain soluble mattere contained in the surrounding water, and giving back to it certain others; these con- tinual exchanges, like those between two vessels separated by a porous partition, would create an everchanging vortex around the little organism. As for the temporary prolongations or pseudopodia which the amoeba seems to make, they would be not so much given out by it as attracted from it by a kind of inhalation or suction of the surrounding medium.' In the same way we may perhaps come to explain the more complex movements which the Infusorian makes with its vibratory cilia, which, more- over, are probably only fixed pseudopodia.
But scientists are far from agreed on the value of ex- planations and schemas of this sort. Chemists have pointed out that even in the organic^not to go so far as the organized — science has reconstructed hitherto nothing but waste products of vital activity; the peculiarly active plastic substances obstinately defy synthesis. One of the most notable naturalists of our titne has insisted on the opposition of two orders of phenomena observed in living tissues, anagenesis and katagenesis. The role of the anagenetic energies is to raise the inferior energies
' Rhumbler, Vtrruch einer mechanischen Erkliimng dtr indvtkUn Zell- und Kemiextung (Roux'a Archiv, 1896).
'Berlhold, StwOen Hber Protoplasmameckanik, LoipKJg, 1886, p. 102. Cf. the explanation proposed by Le Dantec, Thtorie nouveUe de la vi*, Paris, 1896, p. 60.
K.I Biology, Physics and Chemistry 35
^Pto their own level by assimilating inorganic substances. They construct the tissues. On the other hand, the actual functioning of life (excepting, of course, assimilation, growth, and reproduction) is of the katagenetic order, exhibiting the fall, not the rise, of energy. It is only with these facts of katagenetic order that phystco-chemistry deals — that is, in short, with the dead and not with the living.' The other kind of facts certainly seem to defy phj-sico-chemical analysis, even if they are not anagenetic in the proper sense of the word. As for the artificial nitation of the outward appearance of protoplasm, should I real theoretic importance be attached to this when the B^question of the physical framework of protoplasm is not Eyet settled? We are still further from compounding pro- ■-toplasra chemically. Finally, a physico-chemical ex- | Iplanation of the motions of the amoeba, and a fortiori of ' Ithe behavior of the Infusoria, seems impossible to many f of those who have closely observed these rudimentary organisms. Even in these humblest manifestations of life they discover traces of an effective psychological activ- ity.* But instructive above all is the fact that the ten- dency to explain everj-thing by physics and chemistry is discouraged rather than strengthened by deep study of histological phenomena. Such is the conclusion of the truly admirable book which the histologist E. B. Wilson
' Oope, The Primary Fadora of Organic Evolviion, Chicago, 1896, pp. 475-484.
■M&upos. "Etude des infusoirea cUi^a*' (Arch, de toohgie erpiri- mentalt, 1S83, pp. 47, 491, 518, 649. in particular). P. Vignon, Re- dtiBrches de eytologie gintrale aur la fpUhiliitmt, PariB, 1902, p. 655. A piotound study of the motioDB of the Infusoria and a very penetrating ctitidnn of the idea of tropiam have been mode recently by Jennings (/ContribiUiont to the Study of Ihe Behavior of Lower Organisms, Wash- ington, 1904). The "type of behavior*' of theae tower organisnis, aa Jennings defines it (pp. 237-252), ia unquestionably of (be psychological order.
36^ ' Creative Evolution
has devoted to the development of the cell: "ITie study of the cell has, on the whole, seemed to widen rather than to narrow the enormous gap that separates even the lowest forms of life from the inorganic world.'"
To sum up, those who are concerned only with the functional activity of the living being are inclined to be- lieve that physics and chemistry will give us the key to biological processes." They have chiefly to do, as a fact, with phenomena that are repeated continually in the living being, as in a chemical retort. This explains, in some measure, the mechanistic tendencies of physiology. On the contrary, those whose attention is concentrated on the minute structure of living tissues, on their genesis and evolution, histologists and embryogenists on the one hand, naturalists on the other, are interested in the retort itself, not merely in its contents. They find that this retort creates its own form through a unique series of acta that really constitute a history. Thus, histologists, em- bryogenists, and naturalists believe far less readily than physiologists in the physico-chemical chaxacter of vital actions.
The fact is, neither one nor the other of these two theories, ndther that which affirms nor that which denies the possi- bihty of chemically producing an elementary organism, can claim the authority of experiment. They are both unverifiable, the former because science has not yet ad- vanced a step toward the chemical synthesis of a living Hubstance, the second because there is no conceivable way of proving expeil mentally the impossibility of a fact. But we have set forth the theoretical reasons which prevent us from likening the living being, a system closed off by nature, to the systems which our science isolates. These
E. B. Wilson, The Celt in Devehpmenl and InkerHanee, 1
18«7, p. 330.
> D8«U«, LaVitetla mort, p. 43.
isolates. These | mlanee. New Yoi^
I.I
Radical Mechamsm
reasons have less force, we acknowledge, in the case of a rudimentary oi^anism like the amoeba, which hardly evolves at all. But they acquire more when we consider a complex organism which goes through a regular cycle of transformations. The more duration marks the living being with its imprint, the more obviously the organism differs from a mere mechanism, over which duration glides without penetrating. And the demonstration has most force when it applies to the evolution of life as a whole, from its humblest origins to its highest forms, inasmuch as this evolution constitutes, through the unity and con- tinuity of the animated matter which supports it, a single indivisible history. Thus viewed, the evolutionist hypothe- sis does not seem so closely akin to the mechanistic con- ception of life as it is generally supposed to be. Of this mechanistic conception we do not claim, of course, to furnish a mathematical and final refutation. But the refutation which we draw from the consideration of real time, and which is, in our opinion, the only refutation possible, becomes the more rigorous and cogent the more frankly the evolutionist hypothesis is assumed. We must dwell a good deal more on this point. But let us first show more clearly the notion of life to which we are leading up.
The mechanistic explanations, we said, hold good for 1 the systems that our thought artificially detaches from the I whole. But of the whole itself and of the systems which, within this whole, seem to take after it, we cannot admit a priori that they are mechanically explicable, for then time would be useless, and even unreal. The essence of mechanical explanation, in fact, is to regard the future and the past as calculable functions of the present, and thus to claim that all is given. On this hypothesis, past, present and future would be open at a glance to a super- human intellect capable of making the calculation. Indeed,
the scientists who have believed in the universality and perfect objectivity of mechanical explanations have, consciously or unconsciously, acted on a hypothesis of this kind. Laplace formulated it with the greatest pre- cision: "An intellect which at a given instant knew all the forces with which nature is animated, and the respective situations of the beings that compose nature — ^supposing the said intellect were vast enough to subject these data to analysis — would embrace in the same formula the motions of the greatest bodies in the universe and those of the slightest atom: nothing would be uncertain for it, and the future, like the past, would be present to its eyes."' And Du Bois-Reymond : "We can imagine the knowledge of nature arrived at a point where the universal process of the world might be represented by a single mathematical fonnula, by one immense system of simultaneous differ- ential equations, from which could be deduced, for each moment, the position, direction, and velocity of every atom of the world. "' Huxley has expressed the same idea in a more concrete fomi: "If the fundamental proposition of evolution is true, that the entire world, living and not living, is the result of the mutual interaction, according to definite laws, of the forces possessed by the molecules of which the primitive nebulosity of the universe was composed, it is no less certain that the existing world lay, potentially, in the cosmic vapor, and that a sufficient intellect could, from a knowledge of the properties of the molecules of that vapor, have predicted, say the state of the Fauna of Great Britain in 1869, with as much cer- tainty as one can say what will happen to the vapor of the breath in a cold winter's day." In such a doctrine,
Laplace, Inirodaction h la ih4orie ajialytiqtie des probabiiiUa ((Euvm compRUa, vol. vii., Paris, 1886, p, vj.).
Du Bois-Rej'mond, Vber die Grenten des Naturerkenntna, I,«ipzig,
time is still spoken of: one pronounces the word, but one does not think of the thing. For time is here deprived of efficacy, and if it does nothing, it is nothing. Radical mechanism implies a metaphysic in which the totality , of the real is postulated complete in eternity, and in which ' the apparent duration of things expresses merely the in- firmity of a mind that cannot know everything at once. But duration is something very different from this for our consciousness, that is to say, for that which is most indisputable in our experience. We perceive duration B8 a stream against which we cannot go. It is the foundar tion of our being, and, as we feet, the very substance of the world in which we live. It is of no use to hold up before our eyes the dazzling prospect of a universal mathe- matic; we cannot sacrifice experience to the requirementa of a system. That is why we reject radical mechanism. -
But radical finalism is quite as unacceptable, and for the same reason. The doctrine of teleology, in its extreme form, as we find it in Leibniz for example, implies that things and beings merely realize a programme previously, uranged. But if there is nothing unforeseen, no invention j or creation in the universe, time is useless again. As in the-' mechanistic hypothesis, here again it is supposed that o// is ffiven. Finalism thus understood is only inverted mechanism. It springs from the same postulate, with this sole difference, that in the movement of our finite intellects along successive things, whose successiveness is reduced to a mere appearance, it holds in front of us the light with which it claims to guide us, instead of putting it behind. It substitutes the attraction of the future for tthe impulsion of the past. But succession remains none le less a mere appearance, as indeed does movement In the doctrine of Leibniz, time is reduced to a
[Oh^^^
40 Creative Evolution
confused perception, relative to the human standpoint,
a perception which would vanish, hke a rising mist, for a
mind seated at the centre of things.
Yet finalism is not, liiie mechanism, a doctrine with fixed rigid outhnes. It admits of as many inflectiona as we like. The mechanistic philosophy is to be taken or left: it must be left if the least grain of dust, by straying from the path foreseea by mechanics, should show the slightest trace of spontaneity. The doctrine of final causes, on the contrary, will never be definitively refuted. If one form of it be put aside, it will take another. Its principle, which is essentially psychological, is very fiexible. It is so extensible, and thereby ao comprehensive, that one accepts something of it as soon as one rejects pure mech- anism. The theory we shall put forward in this book will therefore necessarily partake of finalism to a certain ex- tent. For that reason it is important to intimate exactly what we are going to take of it, and what we mean to leave.