Organismic Biology

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ORGANISMIC BIOLOGY

The term organismalism was coined by the zoologist W. E. Ritter in 1919 to describe the theory that, in his words, "the organism in its totality is as essential to an explanation of its elements as its elements are to an explanation of the organism." Subsequent writers have largely replaced organismal with the more euphonious organismic as a title for this theory, for the many variations on its main theme, and for some subordinate but supporting doctrines concerning the teleological and historical character of organisms.

Ritter regards Aristotle as the founder and most distinguished exponent of the organismic theory. But Aristotle is also claimed as the father of vitalism, a view that organismic biologists in general reject. In fact, there is considerable affinity between the two schools. They both agree that the methods of the physical sciences are applicable to the study of organisms but insist that these methods cannot tell the whole story; they agree that the "form" of the single whole organism is in some sense a factor in embryological development, animal behavior, reproduction, and physiology; and they both insist on the propriety of a teleological point of view. On all of these points, Aristotle not only agrees but presents, in his own terminology, careful and persuasive arguments in their favor. But organismic biology and vitalism differ in one fundamental respect: The latter holds (and the former denies) that the characteristic features of organic activity—all of which fall under the heading of "regulation"—are caused by the presence in the organism of a nonphysical but substantial entity. There are different interpretations of Aristotle (which we cannot examine here) on the question of whether he believes there are such vital entities. In this writer's view, Aristotle is clearly a vitalist.

The affinity between vitalism and organismic biology is more than an accident. In the history of biology it is difficult to disentangle vitalistic and organismic strands, since both schools are concerned with the same sorts of problems and speak the same sort of language. The distinction between them was drawn clearly only in the twentieth century. Organismic biology may be described as an attempt to achieve the aims of the murky organismic-vitalistic tradition, without appeal to vital entities.

The writings of contemporary organismic biologists present a number of difficulties for a philosophical commentator. The position of organismic biology is usually stated in a vocabulary that plays little or no theoretical role in the working language of biology. For example, "whole," "unity," "integrity," "part," "form," "principle," "understanding," and "significance" all occur frequently in their works. Now any biologist will use these terms occasionally in the course of his professional writing, just because they are perfectly good words in the English language. But they are not technical expressions; they are not, in ordinary usage, laden with biological theory; and they are trouble-free only when employed in contexts that make clear their function as items in the common language. The organismic biologist, however, makes them bear a heavy burden in the description of the nature of living organisms. And many, but by no means all, organismic biologists also assign a great deal of weight to some rather mysterious formulas. Here are a few: "The whole acts as a causal unit … on its own parts" (W. E. Agar); "The living body and its physiological environment form an organic whole, the parts of which cannot be understood in separation from one another" (J. S. Haldane); "No part of any organism can be rightly interpreted except as part of an individual organism" (W. E. Ritter). And here are a few more that are characteristic but not direct quotations: "The organic whole is greater than the sum of its parts"; "Knowledge of the goal of an animal's behavior is necessary for understanding its significance"; "Biological theory should be autonomous, with concepts and laws of its own." These formulas may be termed "mysterious" because, according to their most natural interpretations (as will be argued), they are all the barest of truisms.

Two additional points should be mentioned. Organismic biologists have employed some of the more obscure technical conceptions of speculative philosophy, such as "formal cause," "emergence," "hormic," "telic," and so on. And since their writings are a minority report on biological phenomena, organismic biologists are often polemical, engaging in denunciations of other biologists—"mechanists," "elementalists," and "reductionists"—whose positions they leave just as obscure as their own. For all of these reasons, an account of the organismic position that aims at answering the questions likely to be raised by philosophers of science involves elements of reconstruction and interpretation. Thus, a fuller description of the position and an interpretation designed to do justice both to the letter and spirit of the organismic tradition follows.

The Position of Organismic Biology

All organismic biologists hold that there is a gulf between organic and inorganic phenomena in one or more of the following respects.

organic unity

Organic systems are so organized that the activities of the whole cannot be understood as the sum of the activities of the parts. All members of the school agree on this point. As the term organismic implies, the most important example of such wholes is the single organism, but there are others, such as cells, organs, colonies, and some populations.

J. H. Woodger, whose Biological Principles is the most careful and extensive exposition of organismic biology, explains the conception of organic unity in the following way. Consider a system W that is totally composed of physicochemical parts—elementary particles, for example. The activities of these parts are described by the laws of physics. These particles may be the sole constituents of other systems (for example, molecules) which also totally compose W and which exhibit, in addition to activities described by the laws of physics, other activities described by the laws of chemistry. Molecules may similarly be the sole constituents of other systems, which are in turn the constituents …, up to the whole system W. In Woodger's terminology, W exhibits a series of "levels of organization." The parts of W belong to a particular level, its physical parts to the physical level, its chemical parts to the chemical level, and so on. System W constitutes a perfect "hierarchy" of parts from levels 0 (zero) to n (a finite number), if 0-level parts are the sole constituents of all 1-level parts, and if every part at each level i (any given level) except the 0-level is totally composed of parts at level i –1.

Woodger points out that organisms are not perfect hierarchies, since some parts of the organism at an i –level may have parts at the i –2 level, while the i –2 parts are not organized into i –1 parts (for instance, blood has cellular and chemical but noncellular parts). Nevertheless, he contends, organisms approximate to a hierarchical organization. If we ignore deviations from the perfect hierarchy, we may let W represent a whole organism, and we may say that its 0-level parts are physical parts. Now this analysis permits us to say that the organism is composed totally of physical parts. Perhaps some philosophical materialists would be content with this thesis; at any rate, if it is true, it rules out vitalism. But it is false that the organism is composed only of physical parts, for there are parts at higher levels of organization. It is Woodger's contention, and a general thesis of organismic biology, that the laws which determine the behavior of the parts at a given level of organization are silent about some aspects of the behavior of the parts at the higher levels. To use an extreme example, the laws of quantum physics have nothing to say on the question of why honeybees kill their drones. According to Woodger, it is necessary to study the relations between the relata at each level of organization. In order to understand the behavior of cells during morphogenesis, for example, we must develop a theory of cell relations and not be content, for example, with only a theory of the relations between molecules.

determining features of the whole

The parts of organic wholes not only exhibit patterns of behavior in virtue of their relations to other parts at the same level of organization, but in addition, some of the features of the parts at a given level are determined by the pattern of organization at higher (and, of course, at lower) levels of organization. This is the general form of the special thesis that the properties of the whole determine the properties of the part; and it seems to have the methodological consequence that a theory of the elements at a given level could not be complete without a theory of the elements at the higher levels. Woodger puts the point this way: the parts of organisms must be studied in situ, for we cannot learn how they would behave in situ by studying them in isolation.

teleological behavior of organisms

One kind of activity, which is a consequence of organization at a level higher than that of the organism's physical parts, is directive or teleological behavior. Directiveness is an aspect of organisms that is shown in their physiology, in the behavior of individual animals, and in the social systems of some animals; and an account of directiveness is not only legitimate but necessary. E. S. Russell argues that since directiveness (processes aimed at the production and maintenance of organic unities) is a fact, then a physiological process, or piece of animal behavior, cannot be understood until we understand its function or its goal.

Interpretation of Organismic Biology

It was remarked above that if we give the slogans of organismic biology their most direct interpretations, they are nothing more than truisms. Consider, for example, the statement that the whole (if it is an organic unity) is more than the sum of its parts. This looks like a simple warning against the fallacy of composition: we are being warned, for example, that from the premise "No part of a bird can fly" we cannot infer "No whole bird can fly." No weighty volume is required to convince us that a whole may have numberless properties that its parts lack. Of course, there are other possible interpretations of the slogan. It might be taken to mean, especially in the form "The behavior of the whole is more than the sum of the behavior of its parts," that no description of the behavior of the parts could be a description of the behavior of the whole. So far from being a truism, this is obviously false. Finally, it might be taken to mean something like the following. Employing an analysis of Ernest Nagel, we might say that the behavior B of a system S is more than the sum of the behavior b ₁, b ₂, · · ·, b_n of its parts s ₁, s ₂, · · ·, s_n, with respect to an antecedently specified theory T, if (1) B is an instance of a law L ; (2) L is not part of T : (3) the laws in T describe s ₁, s ₂, · · ·, s_n in such a way that they explain b ₁, b ₂, · · ·, b_n ; and (4) L is not deducible from a description of s ₁, s ₂, · · ·, s_n together with laws in T. An important point to notice here is that B can be identical with events b ₁, b ₂, · · ·, b_n, and yet the law of which B is an instance is not derivable from the laws of which b ₁, b ₂, · · ·, b_n are instances.

This account makes the "more than" relation relative to a body of theory. Relative to existing physical and chemical theories, it is true (but perhaps not a truism) that much organic activity is more than the sum of the physical and chemical activities of its parts. The thesis that there are cases of higher-level behavior that will remain greater than the sum of the behavior of its physical parts, for all possible physical theories, is the doctrine of emergence, which many organismic biologists believe to be true. But it is essential to note two points—first, that the thesis is dubious and unproved, and second, that one can be an organismic biologist without believing it (L. von Bertalanffy is an example).

Let us now look at two more formulas of the organismic biologists. Woodger holds that an organic part, such as a cell, has properties in the organism that it does not have in isolation from the organism. This, too, is a truism: An excised eye lacks the property of contributing to the sight of its former owner. Now if we add, as Woodger does, that the properties of the part in the whole could not be uncovered by studying the part outside the whole, the thesis reduces to the thesis of emergence. And certainly, one of the commonest scientific procedures consists in predicting the behavior of a part in a system that has not yet been studied, although this prediction is assuredly made on the basis of knowledge gained by studying the part—not in "isolation," but as a part of other systems. For instance, the behavior of an electron in a cathode ray tube allows us to predict the electron's behavior in a cyclotron.

Finally, we may consider E. S. Russell's remark that understanding the significance of an animal's behavior requires understanding its goal. This, at least on Russell's interpretation, is a truism, for he connects the notion of a goal with the notion of adaptive value for the animal and identifies "significance" with adaptive value.

Omitting specific discussion of the other formulas cited, the general point is clear: Organismic biology seems to collapse either into doctrines that are not controversial or into unclarified, unproved, and dubious assertions about emergence, unpredictability, and irreducibility. Nevertheless, organismic biology is an important and valuable movement, for the following reasons.

First, organismic biology is perfectly correct in pointing out that there are levels of organization above the chemical level which exhibit laws of behavior that are not exhibited at lower levels (for example, molecules do not sting other molecules to death). Higher-level behavior can be treated without reference to behavior at lower levels, which means that the biologist can (and indeed does) construct concepts that are tailored to the description of higher-level behavior. The principles at the higher levels must be formulated before the question of their reducibility to lower level principles can even be considered. A biochemical geneticist is not only a biochemist; he is also a geneticist, because he is involved in elucidating the processes involved in the sort of gross biological phenomena studied by Gregor Mendel.

Second, the insistence of organismic biologists on the importance of functional analysis is well founded. Focusing on the biological ends of physiological and behavioral processes provides the only means for developing the conceptual schemes that are needed in morphology, ethology, evolution theory, and other branches of biology. This point is developed in detail in Morton Beckner's Biological Way of Thought.

Third, although organismic biology is a set of truisms, it is none the worse for being so. The trouble with truisms is their great number: there are so many that we easily overlook, sometimes systematically, some of the most important ones. Even though in fact many biologists agree with the organismic position, they will say that they disagree. This leads to the position (generally deleterious in the sciences) of the scientist's doing one thing and describing it as if he were doing something else.

To sum up, organismic biology is to be interpreted as a series of methodological proposals, based on certain very general features of the organism—namely, the existence in the organism of levels of organization with the biological ends of maintenance and reproduction. These features are sufficient to justify "a free, autonomous biology, with concepts and laws of its own," whether or not the higher levels are ultimately reducible to the lower ones.