For we shall be chary of bestowing the name “proof” except on what is a proof indeed, of course according to our critical conviction. Vitalistic views in biology have arisen in rather numerous forms during the last fifteen years, especially in Germany—though in very strong contrast to the so-called official German biology—but I can only admit that one of all the arguments of “neo-vitalism” has proved its statements. I refer to the theory of “morphaesthesia” as developed by Noll, which we shall study briefly in the next lecture. I cannot concede that Reinke or Schneider or Pauly have really proved what they believe, and I cannot even allow to the most original thinker in this field, Gustav Wolff, that he has given a real demonstration of his views. He states that the existence of so-called “primary purposefulness,” that is, the existence of adaptive processes, which cannot be imagined to have arisen on Darwinian principles, is able to prove vitalism; but I say that it only proves teleology, which is a broader concept than vitalism.
The possibility of a machine at the root of the phenomena in question always has to be excluded in order that vitalism may be proved, and I cannot grant that the necessity of such an exclusion has been actually shown by any of my fellow-combatants against so-called mechanism, except Noll.[66]
The Logic of our First Proof of Vitalism
Let us devote the end of our present lecture to an account of the logical means by which it has been possible to develop what we hope will be regarded as a true proof of life autonomy.
Firstly, we have looked upon the phenomena of morphogenesis without any prepossessions; we may say that we have fully surrendered ourselves to them; we have not attacked them with any sort of dogmatism except the inherent dogmatism of all reasoning. But this dogmatism, if it may be called so, does not postulate that the results of the inorganic doctrines must hold for the organic world, but only that both the inorganic and the organic must be subject to certain most general principles.
By studying life as a given phenomenon, by fully devoting ourselves to our problem, we not only have analysed into its last elements what was given to us as our subject, but we also, more actively, have created new combinations out of those elements: and it was from the discussion of these positive constructions that our argument for vitalism was derived.
We have analysed morphogenesis into elementary processes, means, potency, formative stimulus, just as the physicist analyses mechanics into time, velocity, mass, and force; we have then rearranged our elements into “systems”—the equipotential systems, the harmonious-equipotential system in particular, just as the physicist composes his elements into the concepts of momentum or of kinetic energy or of work. And finally, we have discussed our compositions and have obtained our result, just as the physicist gets his ultimate results by discussing work and kinetic energy and momentum.
Of course the comparison is by no means intended to show that mechanics and biology are sciences of the same kind. In my opinion, they are not so at all; but nevertheless there do exist similarities of a logical kind between them.
And it is not the formal, logical character alone which allows us to compare biology with other natural sciences: there is still something more, there is one kind of assumption or postulate, or whatever you may choose to call it, without which all science whatever would be altogether impossible. I refer to the concept of universality. All concepts about nature which are gained by positive construction out of elements resulting from analysis, claim to be of universal validity; without that claim there could indeed be no science.
Of course this is no place for a lecture on methodology, and it therefore must suffice to make one remark with special regard to our purpose, which we should like to emphasise. Our concept of the harmonious-equipotential system—say rather, our concept of the prospective potency itself—presumes the understanding that indeed all blastomeres and all stems of Tubularia, including those upon which we have not carried out our experiments, will behave like those we have experimented with; and those concepts also presume that a certain germ of Echinus, A, the blastomeres of which were not separated, would have given two whole larvae, if separation had taken place, while another germ, B, which actually gave us two larvae after separation, would only have given one without it. Without this presumption the concept of “potency” is meaningless, and, indeed, every assumption of a “faculty” or a “possibility” would be meaningless in the whole area of science.