by Corry Shores
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[Note: All boldface and underlining is my own. It is intended for skimming purposes. Bracketed comments are also my own explanations or interpretations.]
Henry Somers-Hall
Hegel, Deleuze, and the Critique of Representation.
Dialectics of Negation and Difference
Part 3: Beyond Representation
Chapter 7: Hegel, Deleuze, and the Structure of the Organism
Subdivision 7: Teratology and Teleology
Brief Summary:
Geoffroy’s homological theory provides an account of the variations in anatomy, which becomes central to the theory of evolution. For Darwin different species have homologous forms on account of common ancestors. And anatomical parts can evolve according to how their functions alter. Cuvier's teleological theory of anatomy is not compatible with evolution, [because were a part’s function to change, it is no longer the same part, and thus such an evolutionary connection cannot be observed using this approach.] Also, Geoffrey’s homology or unity of composition is like Deleuze’s Idea.
Summary
Previously we examined Geoffroy’s homology theory of anatomy. Structures in different species can be identified on the basis of sharing one-to-one correspondences with an abstract, transcendental model which may be expressed in numerous species. Unlike Cuvier’s anatomy, Geoffrey’s is not based on teleological function; so for Cuvier a fin and an arm would not be the same anatomical part, because they have different purposes, however they would be the same for Cuvier, because its relation to the other parts correspond isomorphically with the transcendental model.
Deleuze characterizes Geoffroy as ‘calling forth monsters’ and Cuvier laying ‘out all fossils in order.’ (229) We saw two sections back that “Cuvier claimed to be able to show the structure of the entire animal from a small set of bones and used this technique successfully to prove the prior existence of now extinct species.” (229d) However, this approach led to there being gaps between species “where the combinations of different parts were not able to form a harmonious, purposive organism.” (230a) In Cuvier’s teleological approach major organs [compared between species] show less differentiation, but “Deviations in minor organs were less likely to affect the optimal functioning of the organism as a whole and could therefore be sustained.” (230) So there is more differentiation found in the lesser important organs. For Aristotle’s teleological account, if there are differences [in terms of deformations], they are deviations from the essence of the species, and were therefore understood as a lack. They were monsters by excess or defect. But Geoffroy provides a positive account of deformity. A deformity is an arrest in a part of the organism that leads to the unity of composition [the isomorphism to the transcendental model] in a different form [so the homology remains but in another expression/actualization].
Thus, he attempted to show that aberrations still followed the principle of the unity of composition: "Monstrosity exists, but not, however, exceptions to the ordinary laws [of nature]." (230)
Also Geoffrey could explain organs changing to new or null functions.
Furthermore, as the form of the organism was not understood in purposive terms, Geoffroy was able to give a positive description of these changes that allowed the organ either to no longer function in the new organism or to change its function. Thus, while we might argue teleologically that the bones in the human skull are separate in infants and later fuse together by claiming that this aids parturition, a teleological account seems implausible of the separation of the same bones in birds, which peck their way out of a shell. (230)
Theory of evolution would benefit from a positive account of the structure of variation, thus both the notions of positive contingency and identity irrespective of function [because they explain variations] would serve a theory of evolution. “This variation will eventually lead to speciation.” (230) Cuvier rejects an evolutionary theory that would say there is a transformism of species, because this would contradict the teleological account [because it would mean that parts change their function, but that means they are not the same parts any more so they cannot be thought of as linked developmentally?] Geoffroy however on the basis of his homological account produces a theory of evolution. Yet “While Geoffroy's account of evolution was incorrect, as it was based on purely environmental factors affecting the developing embryo, what is important is that in moving to a nonteleological account of the organism, an evolutionary account of the organism became possible.” (230) But Darwinian theory is based on the idea of two species with similar structures being homogeneous on account of a common ancestor.
Turning to Darwinian evolution, we can see that the main modification is the replacement, or perhaps grounding, of the unity of composition in an evolutionary account of the organism. For Darwin, therefore, homologies exist because organisms from different species share an ancestor. The theory of homologies thus plays a central role in the formulation of his own account of the organism:
Geoffroy Saint-Hilaire has strongly insisted on the high importance of relative position or connexion in homologous parts; they may differ to almost any extent in form and size, yet remain connected together in the same invariable order . . . what can be more different than the immensely long spiral proboscis of a sphinx-moth, the curious folded one of a bee or bug, and the great jaws of a beetle?--yet all these organs, serving for such widely different purposes, are formed by infinitely many modifications of an upper lip, mandibles, and two pairs of maxillae . . . Nothing can be more hopeless than to attempt to explain this similarity of pattern in members of the same class, by utility or by the doctrine of final causes. (231)
Deleuze thinks Geoffroy is seeking differential relations, and they would fulfill Deleuze’s criteria for the Idea.
He argues that what Geoffroy is aiming at with his emphasis on connections is a field of differential elements (the ideal correlates of the bones) forming specific types of relations (the connections which are central to Geoffroy's account). On this basis, Deleuze claims that the unity of composition functions like a Deleuzian Idea, attempting to fulfill his three criteria, which we discussed in chapter 4 (DR, 184). The elements of the Idea "must have neither sensible form nor conceptual signification," and the unity of composition seems to fulfill this requirement due to the fact that it is essentially nonmetric and topological, therefore differing from the actual structures that express it. Second, "these elements must be determined reciprocally," which in the case of the unity of composition, Deleuze takes to mean that what is central is not the bones themselves, but the connections they hold with other bones. Third, "a multiple ideal connection, a differential relation, must be actualized in diverse spatiotemporal relationships, at the same time as its elements are actually incarnated in a variety of terms and forms." In both Difference and Repetition and A Thousand Plateaus, Deleuze emphasizes that the unity of composition implies that homologies do not exist directly between actual terms "but are understood as the actualisation of an essence, in accordance with reasons and at speeds determined by the environment, with accelerations and interruptions" (DR, 184). That is, we note a homology by recognizing that the actual parts of both organisms are actualizations of the same transcendental essence, the unity of composition, rather than | by a direct correlation of actual terms, as in Cuvier's comparative anatomy. The unity of composition therefore functions, according to Deleuze, much like the virtual, as that which is actualized, while differing in kind from its actualization. (231-232)
Also, for Deleuze, the concept of essence in Geoffroy’s approach is not like the classical understanding of essence but is instead “functions more like a field of accidents, with no privileged form or level of organization.” (232)
However, Deleuze in Difference and Repetition thinks that “Geoffroy's anatomical elements may not be able to support the difference between virtuality and actuality required by the Idea”. (232) Yet in A Thousand Plateaus, Deleuze thinks that Geoffroy’s anatomical elements are like molecular relations that a single abstract animal or machine presents everywhere. But “Geoffroy's anatomical elements may not be able to support the difference between virtuality and actuality required by the Idea”. (232)
So we cannot formulate a theory of evolution on the basis of Cuvier’s teleological approach to anatomy. For, evolution [1] requires the existence of suboptimal organisms and [2] accepts that “structure cannot be determined simply by function, as homologies can be found regardless of the function of the parts in question.” (232) Change of function, which Geoffrey’s approach can describe, is central to the theory of evolution. We turn now to Hegel to see if his philosophy is compatible with evolution. (233)
Somers-Hall, Henry (2012) Hegel, Deleuze, and the Critique of Representation. Dialectics of Negation and Difference. Albany: SUNY.
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