The Science and Philosophy of the Organism

THE HARMONIOUS-EQ

OF THE AUT

cide a question which is to give life its place in Nature, and biology its place in the system of science

neral

genesis may be resolved into the three phenomena expressed by those concepts; in other terms, that morphogenesis may be proved to consist simply and solely of what is expressed by them. Have we indeed succ

these considerations will give us a very clear and simple result by convincin

e a negative one? Wha

ncies, might assure us, perhaps, that, though not yet, still at some future time, a further sort of analysis will be possible: the analysis into the ele

iminary analysis, which possibly might

always possible in fact to account for the typical localisation of every morphogenetic effect by the discovery of a single specific formative stimulus? You will answer me, that such an analysis certainly is no

hogeneti

m from mechanics, and call any part of the organism which is considered as a unit from any morphogenetic point of view, a morphogenetic "system," we may sum up what we have learnt by saying that both the blastoderm o

ltogether indicate the real

the organ proper of restitutions, and which also in each of its elements possesses the same restoring potency; I refer to the well-known cambium. This cambium, therefore, also deserves the name of an "equipotential system." But we know already that its potencies are of t

each of their elements may play every single part in the totality of what will occur in the whole system; it is to this single part that the term "function

ch actual case is in fact a single one, but the potency of any element as such consists in the possibility of many, nay of indefinitely many, single acts: that then might justify us in speaking of our systems as "indefinite equipotential," were it not that another reason makes another title seem still more preferable. There are indeed indefinite singular potencies at work in all of ou

extremes the meaning of the statement that a m

ous-Equipote

less the differentiation of the ectoderm may go on perfectly well and result in a typical little embryo, which is only smaller in its size than

e surface of this cylinder unrolled. It will give us a plane of two definite dimensions, a and b. And now we ha

relation to the length of two lines, drawn at right angles to the bordering lines of the plane; or, to speak analytically, there is a definite actual fate corresponding to each possible value of x and of y. Now, we have been able to state by our experimental work, that the pro

any element of our system depend in all possible cases of development obtainabl

) = f(

ue of the element X is a

prospective value of any element certainly depends on, certainly is a function of, the absolute size of the actually existing part of our system in the particular case. Let s be th

h is bounded by the lines a1 b1, and at another time an equal amount of it which has the lines a2 b2 as its boundaries. Now since in both cases a typical small organism may result on development, we see that, in spite of their equal size the prospective value of every element of the two pieces cut out of the germ may vary even in relation to the direction of the cut itself. Our element, X, may belong to both of these pieces of the same size: its actual fa

Characteristics of an "Harm

ms a b or a1 b1 or a2 b2; its prospec

red; to every value of s and l, which as we know are independent of each other, there corresponds a definite value of the actual prospectivity. Now, of course, there is also a certain factor at work in every actual ca

call this order the "relation of localities in the absolutely normal case." If we keep in mind that the term "prospective potency" is always to contain this order, or, as we may also call it, this "relative proportionality," which, indeed, was the reason for calling our systems "harmonious," then we m

dy of the differentiation of har

armonious-Equip

monious-equipotential systems, and that the same probably is true of many others; we also know that the immature egg of almost all animals belongs to this type, even if a fixed determination of its parts may be established just after maturation. Moreover, we said, when speaking about some new discoveries on form-restitution, that there are many cases in wh

new tubularian head was restored by the combined work of many parts of the stem. Further analysis then taught us that Tubularia indeed is to be regarded as the perfect type of an harmonious-equipotential system: you may cut the stem at whatever level you like: a certain length of the stem will always restore the new head by the co-operation of its parts. As the point of section is of course absolutely at our choice, it is clear, without any further discussion, that the prospective value of each part of the restoring stem is a "function of its position," that it varies with its distance from the end of th

restitution. You notice two rings of longitudinal lines inside the stem; the lines will become walls and then will separate from the stem until they are only connected with it at their basal ends; the new tentacles are ready as soon as that has happened, and a process of growth at the end will serve to

2.-Tub

dranth," with its sho

new hydranth insid

e whole hydranth will be driven out of the perisarc by

a cut either at a1b1

entacles in the

the piece cut at a2b2 whic

n the piece cut at a1c, wh

he normal proportion of our form. Of course such prediction would not have much practical importance in all our cases of morphogenesis, but nevertheless I should like to state here that it is possible; for many scientific authors of recent times have urged the opinion t

3.-Cla

J = openings; K = branchial apparatus

ted branchia

s of reduction of th

whole littl

nisation and become a small white sphere, consisting only of epithelia corresponding to the germ-layers, and of mesenchyme between them, and then, after a certain period of rest, a new organisation will appear. Now this new organisation is not that of a branchial apparatus but represents a very small but complete ascidian (Fig. 13). Such a fact certainly seems to be very important, not to say very surprising; but still another phenomena may be demonstrated on the animal which seems to be even more important. You first isolate the branchial apparatus from the other part of the body, and then you cut it in two, in whatever direction you please. P

better instance of an harm

can only mention here that the common hydra and the flatworm Planaria are very fine examples of them. Bu

r it follows just the very lines which we know already from our study of embryonic organs or from Tubularia; that an harmonious-equipotential system is at the basis of what goes on. Now, you know that all Protozoa are but one highly organised cell: we have therefore here an instance where the so-called "elements" of our harmonious-morphogenetic system are not cells, but s

em of the

had succeeded in obtaining an equation as the expression of all those factors on which the prospective value, the actual fate, of any element of our systems depends, p.v. (X) = f(s, l, E) was the short expression of all the relations involved; s

y the significanc

ental agents having a common resultant? And, if so, of what kind are these agent

ered by "Means" or

sis? We, of course, have to look back to our well-studied "formative stimuli." These stimuli, be they "external" or "internal," come from without with respect to the elementary organ in which any sort of differentiation, and therefore of localisation, occurs: but in our harmonious systems no localising

ormative stimuli; both are entirely unable to account for those kinds of l

nogenetic localisation by any other sort of interaction of part

ed by a Chemical The

biologists, that a chemical compound of a very high degree of complication might be the very basis of both d

f form starting from atypical localities. The mere fact, indeed, that there is such a thing as the regeneration of a leg of a newt-to say nothing about restitution of the harmonious type-simply contradicts,62 it seems to me, the hypothesis, that chemical disintegration of one compoun

ve the reason for the differentiation of our harmonious-equipotential systems, with special regard to the localisation of it; how could it accoun

is disintegrated to the amount of a1; from a1 are formed the two more simple compounds, b and c, both of them in definite quantities; then we have the three chemical individuals, a-a1, b and c, as the constituents of our harmonious system; and it now might be assumed, without any serious difficulty, though with the introduction of some new hypotheses, that the two poles of one of the fundamental axes of symmetry attract b and c respectively, a-a1 remaining unattracted between them. We thus should have the three elementary constituents of the system separated into t

t at all go hand-in-hand with chemical differences; this feature alone would absolutely overthrow any sort of a chemical morphogenetic theory to account for the problem of localisation. Take the typically arranged ring of the mesenchyme cells in our Echinus-gastrula, with its two spherical triangles, so typically localised; look at any sort of skeleton, in Radiolaria, or in starfishes, or in vertebrates: here you have form, real form, but form consisting of only one material. Not only is the arrangement of the elements of form typical here, e.g. the arrangement of the single parts of the skeleton of the hand or foot, but also the special form of each element is typical, e.g. the for

ontradict the hypothesis that a disintegration of compounds might be the directive agency in morphogenesis. To sum up: Specificity of organic form does not go hand-in-hand with specificity of chemical composition, and therefore cannot depend on it; and besides that, specific organic form is such

ble Inside the H

tegration of a compound has failed too. But could there not exist some sort of complicated interactions amongst the parts of the harmonious system themselves? Could there not exist some kind of a real machine in the system, which, if once set going, would result in the di

experiments most strongly contradict it. But, of course, the experiments only showed us that such a machine as he had imagined to exist could not be there, that

constituents also; we therefore understand by the word "machine" a configuration of a much higher degree of complication than for instance a steam-engine is. Of course a machine, whose acting is to be typical with regard to the three dimensions in space, has to be typically constructed with regar

force of organogenesis in general, if only normal, that is to say, if only undisturbed dev

ite another process occurs after parts have been taken away: the devel

s equal to V in amount, and also in V2, in V3, V4 and so on. Indeed, there do exist almost indefinitely many Vn all of which can perform the whole morphogenesis, and all of which therefore ought to possess the machine. But these different portions Vn are only partly different from each other in spatial relation. Many parts of V2 are also parts of V1 and of V3 and of V4 and so on; that is to say, the different volumes Vn overlap each other successively and in such a manner that each following

ne indeed, which is the same

us-equipotential Syst

is system ought to possess a certain unknown

ts total

he equal volumes v,

the unequal volumes

aginable volume, no

achine-theory" o

ture it follows that not only all the different Vn, all of the same size, must possess the hypothetic machine in its completeness, but that all amounts of

led to real

lusion of our rather

of single physical or chemical factors and events, there must be some such thing as a machine. Now the assumption of the existence of a machine proves to be absolutely absurd in the light of t

dimensions of space, cannot remain itself if you remov

morphogenesis has been worth while: it has af

of Morphoge

something else which is to be regarded as the sufficient reason of individual form-production. We now have got the answer to our question, what our constant E consists in. It is not the resulting action of a constellation. It is not only a short expression for a more com

proposition was stated in the form: E is either this, or that, or the other, and it was shown that it could not be any of all these except one, therefore it was proved to be that one. Indeed, I do not see how natural science could argue o

autonomy of life, as proved at least in the field of morphogenesis. I know very well that the word "autonomy" usually means the faculty of giving laws to oneself, and that in this sense it is applied with regard to a community of men; but in our phrase autonomy is to signify the being subjected to laws peculiar to the

reasoning. There can indeed be a sort of direct proof of vitalism, but now is not the time to develop this proof, for it is not of the purely scientific char

tel

onally. The great father of systematic philosophy, Aristotle, as many of you will know, is also to be regarded as the founder of theoretical biology. Moreover, he is the first vitalist in history

ith what Aristotle meant by the word ?ντελ?χεια. We shall use this word only as a sign of our admiration for his great genius; his word is to be a mould which we have filled and shall fill with new conte

in space is produced where no manifoldness was, real "evolutio" is limited to rather insignificant topics. But was there nothing "manifold" previous to morphogenesis? Nothing certainly of an extensive charact

al Remarks

l-important.65 It indeed has been the fault of all vitalism in the past that it rested on weak foundations. Therefore the discussion of the basis underlying our doctrine of the autonomy of life is to occupy us still a considerable time. We shall devote to it two more of this year's lectures and three of the next; we shall examine all sorts of phenomena of life in order to f

t 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, Gusta

n order that vitalism may be proved, and I cannot grant that the necessity of such an exclusion h

our First Pro

the logical means by which it has been possible to develop w

tacked 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 resu

last elements what was given to us as our subject, but we also, more actively, have created new combinations out of tho

d 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

biology are sciences of the same kind. In my opinion, they are not so at all

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 abou

ndeed 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 s

. It therefore is only with this postulate that our first proof of

of pre-established harmony between the scientific object and the scientist, the scientist always getting into his hand

al laws is possible at all; but nature unde

of the universality of scientific concepts-the o