Composite Integrity notes

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Composite Integrity
D'Arcy Wentworth Thompson on Composite Integrity

In various ways our structural problem is beset by "limiting conditions." Not only must rigidity be associated with flexibility, but also stability must be ensured in various positions and attitudes ; and the primary function of support or weight-carrying must be combined with the provision of points

It has been remarked over and over again how harmoni- ously the whole organism hangs together, and how throughout its fabric one part is related and fitted to another in strictly functional correlation.

We tend, as we analyse a thing into its parts or into its properties, to magnify these, to exaggerate their apparent independence, and to hide from ourselves (at least for a time) the essential integrity and individuality of the composite whole.

We divide the body into its organs, the skeleton into its bones, as in very much the same fashion we make a subjective analysis of the mind, according to the teachings of psychology, into component factors: but we know very well that judgment and knowledge, courage or gentleness, love or fear, have no separate existence, but are somehow mere manifestations, or imaginary co-efficients, of a most complex integral.

And likewise, as biologists, we may go so far as to say that even the bones themselves are only in a limited and even a deceptive sense, separate and individual things. The skeleton begins as a continuum, and a continuum it remains all life long. The things that link bone with bone, cartilage, ligaments, membranes, are fashioned out of the same primordial tissue, and come into being -pari jmssu, with the bones themselves.

The entire fabric has its soft parts and its hard, its rigid and its flexible parts ; but until we disrupt and dismember its bony, gristly and fibrous parts, one from another, it exists simply as a "skeleton," as one integral and individual whole.

A bridge was once upon a time a loose heap of pillars and rods and rivets of steel. But the identity of these is lost, just as if they were fused into a solid mass, when once the bridge is built; their separate functions are only to be recognised and analysed in so far as we can analyse the stresses, the tensions and the pressures, which affect this part of the structure or that; and '''these forces are not themselves separate entities, but are the resultants of an analysis of the whole field of force'''.

''Moreover when the bridge is broken it is no* longer a bridge, and all its strength is gone.''

So is it precisely with the skeleton. In it is reflected a field of force : and keeping pace, as it were, in action and interaction with this field of force, the whole skeleton and every part thereof, down to the minute intrinsic structure of the bones themselves, is related in form and in position to the lines of force, to the resistances it has to encounter; for by one of the mysteries of biology, resistance begets resistance, and where pressure falls there growth springs up in strength to meet it.

And, pursuing the same train of thought, we see that all this is true not of the skeleton alone but of the whole fabric of the body. Muscle and bone, for instance, are inseparably associated and connected ; they are moulded one with another ; they come into being together, and act and react together*. We may study them apart, but it is as a concession to our weakness and to the narrow outlook of our minds. We see, dimly perhaps, but yet with all the assurance of conviction, that between muscle and bone there can be no change in the one but it is correlated with changes in the other; that through and through they are '''linked in indissoluble association''' ; that they are only separate entities

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in this limited and subordinate sense, that they are parts of a whole which, when it loses its composite integrity, ceases to exist.


 * (* John Hunter was seldom wrong ; but I cannot believe that he was right when

he said (Scientific Works, ed. Owen, i, p. 371), "The bones, in a mechanical view, appear to be the first that are to be considered. We can study their shape, connections, number, uses, etc., without considering any other part of the body.^' )

'''The biologist, as well as the philosopher, learns to recognise that the whole is not merely the sum of its parts. '''

It is this, and much more than this. For it is not a bundle of parts but an organisation of parts, of parts in their mutual arrangement, fitting one with another, in what Aristotle calls "a single and indivisible principle of unity" ; and this is no merely metaphysical conception, but is in biology the fundamental truth which lies at the basis of Geoffroy's (or Goethe's) law of "compensation," or "balancement of growth."

Nevertheless Darwin found no difficulty in believing that "natural selection will tend in the long run to reduce any part of the organisation, as soon as, through changed habits, it becomes superfluous : without by any means causing some other part to be largely developed in a corresponding degree. (NOTES:  Tautology: reduce any part <=> becomes superfluous)

And conversely, that Natural Selection may perfectly well succeed in largely developing an organ without requiring as a necessary compensation the reduction of some adjoining part*.

This view has been developed into a doctrine of the "independence of single char- acters" (not to be confused with the germinal "unit characters" of Mendelism), especially by the palaeontologists.

(NOTES: This must have been the chain of reasoning to deal with the composite integrity or IC argument back then. It seems genetics was not yet accepted. Needs further review)

Thus Osborn asserts a "principle of hereditary correlation," combined with a " principle of hereditary separability whereby the body is a colony, a mosaic, of single individual and separable charactersf-"

I cannot think that there is more than a small element of truth in this doctrine.

As Kant said, "die Ursache der Art der Existenz bei jedem Theile eines lebenden Korpers ist im Ganzen enthalten..'^

And, according to the trend or aspect of our thought, we may look upon the co-ordinated parts, now as related and fitted to the end or function of the whole, and now as related to or resulting from the physical causes inherent in the entire system of forces to which the whole has been exposed, and under whose influence it has come into being J.


 * Origin of Species, 6th ed. p. 118.

t Atner. Naturalist, April, 1915, p. 198, etc. Cf. infra, p. 727.

J Driesch sees in "Entelechy" that something which differentiates the whole

XVI] THE PROBLEM OF PHYLOGENY 715

It would seem to me that the mechanical principles and phenomena which we have dealt with in this chapter are of no small importance to the morphologist, all the more when he is inclined to direct his study of the skeleton exclusively to the problem of phylogeny; and especially when, according to the methods of modern comparative morphology, he is apt to take the skeleton to pieces, and to draw from the comparison of a series of scapulae, humeri, or individual vertebrae, conclusions as to the descent and relationship of the animals to which they belong.

It would, I dare say, be a gross exaggeration to see in every bone nothing more than a resultant of immediate and direct physical or mechanical conditions ; for to do so would be t® deny the existence, in this connection, of a principle of heredity. And though I have tried throughout this book to lay emphasis on the direct action of causes other than heredity, in short to circum- scribe the employment of the latter as a working hypothesis in morphology, there can still be no question whatsoever but that heredity is a vastly important as well as a mysterious thing; it is one of the great factors in biology, however we may attempt to figure to ourselves, or howsoever we may fail even to imagine, its underlying physical explanation.

But I maintain that it is no less an exaggeration if we tend to neglect these direct physical and mechanical modes of causation altogether, and to see in the characters of a bone merely the results of variation and of heredity, and to trust, in consequence, to those characters as a sure and certain and unquestioned guide to affinity and phylogeny. Comparative anatomy has its physiological side, which filled men's minds in John Hunter day, and in Owen's day ; it has its

from the sum of its parts in the case of the organism:


 * "The organism, we know, is a system the single constituents of which are inorganic in themselves ; only the whole constituted by them in their typical order or arrangement owes its specificity to 'Entelechy'" {Gifford LerAures, p. 2"?9, 1908): and I think it could be shewn that many other philosophers have said precisely the same thing.

(NOTES: Entelechy seems to have been some sort of vernacular for IC, by Gifford Leraures - DO A SEARCH)

So far as the argument goes, I fail to see how this Entelechy is shewn to be peculiarly or specifically related to the living organism.

'''The conception that the whole is ahvays somethini^ very different from its parts is a very ancient doctrine. '''

The reader will perhaps remember how, in another vein, the theme is treated by Martinus Seriblerus: "In every Jack there is a meat-roasting Quality, which neither resides in the fly, nor in the weight, nor in any particular wheel of the Jack, but is the result of the whole composition; etc., etc."

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classificatory and phylogenetic aspect, which has all but filled men's minds during the last couple of generations; and we can lose sight of neither aspect without risk of error and misconception.

It is certain that the question of phylogeny, always difficult, becomes especially so in cases where a great change of physical or mechanical conditions has come about, and where accordingly the physical and physiological factors in connection with change of form are bound to be large. To discuss these questions at length would be to enter on a discussion of Lamarck's philosophy of biology, and of many other things besides. But let us take one single illustration.