Monday, September 23, 2024

The Unfolding Continuity of Embryology

After our in-depth discussion of the fibrous structure of universe, let's step back for a moment and try to pinpoint the crucial difference between viewing the universe as a collection of material particles and viewing it as a collection of ideal fibers.  The chapter on "neomaterialism" (15) indicates that this difference is sometimes more a question of attitude than on of arguing over facts (NF, 156).  For example, Ruyer point out that Schrödinger's famous thesis that the organism is an aperiodic crystal can equally well be read as asserting that an aperiodic crystal is an organism (NF, 154).  In that case, where exactly does the difference between neomaterialism and neofinalism lie?  Ruyer locates it in "the recognition of lines of individual continuity" (NF, 162) but what exactly does this mean? 

From a high level, I think the easiest way to approach this question is through the central metaphor of Neofinalism -- the embryo.  Everyone can see that what begins as an embryo ends up as an adult organism.  The obvious question is where this order comes from.  Ruyer's answer is, in short, that the whole structure of the organism, along with its differentiated parts, is there from the start as an Ideal Individual.  This ideal form is like a continuous virtual thread that links and organizes every stage of development as a means to an end.  By contrast, the neo-materialist and (as we'll see in the next several chapters 16, 17) neo-Darwinist accounts explain this order as nothing more than chance.  These theories banish the notion of Ideas existing from the beginning and operating across time, and reduce everything to the blind mechanism of material particles interacting moment to moment.  Any order, up to and including the mind of the theorizing scientist, which arises from these mechanisms is illusory, epiphenomenal, and just a matter of speaking.  While we can always trace the adult organism back to the embryo through a series of step-by-step chemical reactions that form an actual thread, when we reach this starting point we discover that it is 'just' another collection of molecules.  In a real sense, these theories imply that the embryo 'just happens' to produce an organism, or, if we scratch deeper, we discover random mutations that 'just happen' to produce the viable embryo.  

So with NeoDarwinism and NeoMaterialism, there's always an actual thread of step-wise causal segments that unfold in time, but these events are, by hypothesis, not shaped by a continuous virtual line that operates across time.  This situates the key difference between the ideal and the material in our understanding of time.  Is time an empty space-like container that only exists conceptually as sub-divided into instantaneous moments like so many tiny line segments?  Or does time have an indivisible reality of its own that underlies the integration of these moments into a continuous line (similar to Bergson's duration?).  Ideas are inherently active entities that cannot be reduced to a single moment, things that die or dissolve if you try to hold them still, whereas the essence of material things lies in their static instantaneous substance, though they may later happen to move around.  It's akin to the difference between seeing the real number line as just a collection of points that happen to look continuous, and seeing it as a continuum that can be differentiated into a collection of points.  Notice that each view converts into the other when you take them to their limits.

Precisely because a line is continuous virtually, it can only actualize itself discontinuously.  Despite the fact that it's there as a virtual from the beginning, the adult organism still comes into actual existence through the steps of embryonic development.  An actual organism differs radically from an actual embryo, and yet there is an ideal continuity that stretches between these two.  Similarly, an actual molecule differs from an actual organism, and yet the organism is a form of development of the molecule, something, as Spinoza would have said, that the molecule "can do", just like thinking is in turn something that the body can do.  I think this gets to the root of why Ruyer's description of fibers can be confusing at times -- the continuity of the virtual fiber isn't distinct from the transformation of one actual entity into another.  In short, the cosmic embryo at the heart of Ruyer's scheme never really stops developing.  Which explains why even this far into a book called Neofinalism Ruyer has yet to clearly tell us what end any of his subjects work towards.  Ideal individuals, as absolute surfaces, stretch across time and impose a norm on a certain domain of spatiotemporal forms.  They organize these into something that looks like a development.  But this isn't a development towards the last form in this series -- it isn't a goal directed development towards an equilibrium form defined in advance.  Ruyer repeatedly talks about improvisation and freedom and the fact that the end of the organism isn't simple self-maintenance, but it's still easy to slip into thinking that ideal individuals are effectively just copies of the actual individuals that appear stable to us.  Instead, ideal individuals are like a vector of activity, a tendency that holds together the trajectory of a certain stretch of fiber.  But this stretch is in continuity with sub-individuals which came before it and super-individuals which follow it, just as the formation of our embryonic limb is in continuity with the bilateral differentiation which precedes it and the digital differentiations which will follow it.  Each stage in the process is a separate tendency, a distinct and well defined potential of the initial embryo that contains them all simultaneously, but in an ordered continuity of unfolding.  Thus, each new level is a development of the previous one, and not a new composition (NF, 155), a memory and not a creation or emergence

After that abstract rhapsody, let's return to the text.

Another way to approach the importance of Ruyer's theory of fibers is to contrast it in detail with the reductionist tendency of neo-materialism, and this is exactly what he does in chapter 15.  Ruyer chooses Schrödinger's classic What is Life? to represent the neo-materialist position.  Since I happened to have it sitting on the shelf, I was able to quickly read through this justly famous little set of lectures.  It brilliantly drives home the now commonplace but actually rather mind-blowing point that the entire organism develops from a single particular molecule.  And reading it illuminates Ruyer's equally brilliant critique of the way Schrödinger misinterprets his own thesis as a reduction of the organism to a molecule.  In fact, what Schrödinger discovers here fits perfectly with the central idea of the wave mechanics he helped invent -- the molecule is already an 'organism', so it cannot be a question of reduction, but of the continuity of 'organic' development across what we think of as distinct levels.  As we saw last time, the quantum particles that appear to form the simplest unities are nevertheless still domains of absolute survey just like the organisms and consciousnesses that will develop from them.  All these levels are equally real individuals that exist in continuity alongside one another on the same ideal plane, even if when they are unfolded in actuality they appear as separate levels of composition. 

Schrödinger's lectures distinguish two ways that order can appear in the universe, which he calls "order from disorder" and "order from order" respectively.  Most of macroscopic physics, at least insofar as it pertains to biology, is based on the central idea of statistical mechanics -- order can arise from disorder when the number of independent parts becomes large.  This accounts for why we see very precise phenomenon like the equilibrium distribution of positions and speeds of gas molecules in a volume, even though the underlying motion of the molecules is quite random. By contrast, the order we see in an organism is not an order created by thermodynamic equilibrium.  Though the organism is composed of many many molecules, its visible order is a development of the order already present within just a tiny fraction of those molecules -- the well ordered aperiodic crystal we now call DNA.  In some sense, the organism is like a giant molecule, an amplification of the order present in its tiny embryonic molecular seed.  And of course, the structure, stability, and mutability of this seed are all due to quantum effects that hold it together as a unit.  While Schrödinger construes this observation as a reduction of the organism to a "clock-work" system (WL, 81), he uses this term in a sense we don't normally give it now.  He explicitly opposes a clock-work system to a statistical one.  An example of a purely clock-work system would be something like the friction-less pendulum, not the actual mechanical linkages of a watch one has to periodically wind.  That is, a clock-work system is an ideal one, one whose behavior is deducible from first principles as a dynamic mathematical form that continues in perpetuity.  In fact, no real physical system is truly a clock-work until we reach the realm of the quantum, either because we examine such a small form, or because we cool a larger one down to absolute zero (WL, 84).  In either case, we reach a moment when actual things stop behaving like substantial particles and start behaving exactly like mathematical ideas.  Which is to say that Schrödinger's clock-work is precisely the ideal individual that Ruyer characterizes as a domain of absolute survey.  So it turns out that Schrödinger, who explicitly tells us that his conclusion that the organism is a clock-work sounds ridiculous (WL, 82), is a neofinalist without realizing it!  His 'order from order' is exactly the line of developmental continuity of an ideal fiber that Ruyer has been discussing.  And it is exactly opposed to the 'order from disorder' that is merely a consequence of the law of large numbers which we invoke when we deal with a statistical aggregate that doesn't constitute a true individual fiber in Ruyer's sense.  In Ruyer's eyes, Schrödinger's only failure lies in not accepting the implications of his own conclusion, implications which the father of quantum mechanics was in a perfect position to appreciate.   

In the following chapters on neoDarwinism (16 and 17), Ruyer goes on to deal with the next logical step in the attempt to reduce the inherent trans-spatiotemporal unity of the organism to the illusory outcome of a purely statistical and step-by-step causal process.  Sure, we can hear a critic say, the organism is not a statistical phenomena in the physicists normal sense of something at thermodynamic equilibrium.  Granted, it's order derives from a development or amplification of the order already present in its genome.  But the order of this genome is itself the result of natural selection, a process that in the final analysis is just a differential sorting of fortuitous mutations.  So the adult organism reduces to the genome (as Schrödinger suggested and modern genetics supposedly confirms) and the genome reduces to chance, without the need for any finalist activity along the way.  As a result, the neo-reductionist argues, Ruyer's fiber of development is nothing more than an after the fact anthropocentric imposition of coherent form on evolution's random walk.

Ruyer produces some powerful arguments against these objections, not least of which is a version of the very first argument he made in the book -- the neo-reductionist incoherently claims that the meaning of the universe is its meaninglessness, that it's only order is disorder (NF, 166).  And, certainly, I don't know a single scientist that behaves as if they are nothing more than a random sequence of genetic variations.  But this is just the beginning of his critique, and these chapters are both quite technical refutations of the overly grandiose interpretations of evolutionary theory that pass as orthodoxy these days.  While I'll spare us the details, I do think there are two main points worth highlighting.  As always, Ruyer is not critiquing the veracity or usefulness of specific scientific fact, but only the sophomoric philosophical interpretation imposed upon these facts (ie. Dawinism and Materialism).  So he accepts that both natural selection and genetics are real forces shaping organisms, while rejecting the pretense that these theories explain everything about the organism.  His two main points are then simply: 1) the failure of the "Democritean" ambition (NF, 177) of the theory of natural selection to eliminate any possible form of order other than accumulations of chance and 2) the failure of of genetics to uncover a one-to-one correspondence between phenotype and genotype (NF, 187).  Together these failures open up the space for us to consider other sources of order in the organic world that do not operate in the step-by-step causal manner these theories insist upon.  And this of course is Ruyer's deepest point -- there are sources of order outside space and time

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