Monday, July 5, 2010

Crystals, Fabrics, and Fields (3)

In Haraway's review of the work of Joseph Needham:

"The use of the fiber and tissue metaphor amply expresses Needham's mature conception of the resolution of the field-particle dichotomy in biological field theory ... Fields invited the introduction of topographical models and reasoning. For example, Needham described, a kind of qualitative mathematical model of an amphibian neurula ... Needham believed that fields were distinguished from simple geographic regions of the embryo by three criteria: any given point within the field force had to possess a given quality, a given direction, and a given intensity. Fields were judged in terms of instability and successive equilibrium positions." [124-5]

Haraway's observations here matter because they make us reconsider what portion of our thinking is metaphorical and what is nonmetaphorical or other-than-metaphorical in some way. It makes perfect sense to reason topographically with continuously varying quantities of different values present in certain areas of the cell once you have decided to model parts of the cell as fields. But would such reasoning arise in the absence of a comparable metaphor?

Further:

"Explanation implies a picture, and analogy is a vehicle for connecting the internal subjective perception of the structure of a phenomenon with the public function of theory building." [106]

In Haraway's review of the work of Paul Weiss:

"After observing the intact lamella, Weiss and Ferris took electron microscopic pictures of reconstruction of the membrane after wounding. The sequence of events was easily determined: Epidermal cells first migrated over and covered the wound. Fairly uniform fibers of small size (less than 200 Å) spread in the space between the underside of the epidermis and the subjacent fibroblasts. These small fibers were oriented at random. Then, proceeding from the epidermal face downward, a "wave of organization" spread over the fiber mass, straightening and orienting its elements. The fibers became packed in the characteristic layered structure and enlarged until they were about 500 Å in diameter ... Weiss was profoundly impressed with orthogonal tissue organization and its genesis. He frequently drew from the work in lectures and general speculative articles ... The "weaving of threads into fabrics, such as we find in living tissue" seemed to necessitate the judgment that "some sort of 'macro-crystallinity' [was] a basic property of living systems"." [170]

Can the liquid crystal bridge atomistic physics and the orders of biological organization? The idea of a 'wave or organization' spread over some part of the cell is striking or even eerie. And yet researchers observe this sort of thing all the time. But why?

Haraway's conclusion to Crystals, Fabrics, and Fields joins the organicism of Harrison, Needham and Weiss in both image and world view:

"For Harrison the limb field is like a liquid crystal and unlike a jigsaw puzzle. for Needham the embryo is like history interpreted from a Marxist viewpoint and unlike an automobile with gear sifts. For Weiss butterfly behavior is like a random search and self-correcting device and unlike a deterministic stimulus-response machine. Such a catalog could be continued indefinitely, but the basic point is that organicists, even granting their internal differences, share central perceptions on the level of images and language." [205]

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