(R)evolutionary Thought

Posted on January 12, 2010

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Impediments to understanding have been with us throughout the ages.  It is important to note that I am not talking specifically about a particular individual’s impediments to understanding, which may stem from a variety of unknown sources, but more or less the barriers that restrain a culture or society in accepting radically new ways of thinking about old issues.  The destruction of such barriers are numerous throughout our history, and one need only be reminded of the mental revolutions that needed to have taken place in order for the abolishment of slavery, or women’s suffrage to have been attained.  Events of such a nature span through as large a swath of human history as they do through intellectual disciplines.  But nowhere are these revolutions of thought, these coups of orthodoxy, more numerous and necessary than in the sciences, and no idea in science can be said to have had such an impediment to understanding as did Darwinian evolution.  The impediments to the understanding of evolution took many forms during its inception in 1859 with the publication of Darwin’s evolutionary treatise, On the Origin of Species.  An evaluation of a few of these potential barriers requires some discussion.

The first and perhaps most obvious reason for evolution’s rough reception is because of its human implications; that is, the inclusion of human beings with the rest of the animal kingdom.  Those with a “fallen angel” view of humans will naturally rebel against the less glamorous “risen ape” view, and this knocking of humans off their supposed pedestal is surely the largest source of anti-evolutionary strife that Darwin encountered, and it is still operant today.  However, because an idea is offensive to some does not mean that it is unintelligible to them, and therefore religious motivation cannot be counted as a true impediment to the understanding of evolution, but only as a source of unwillingness to accept its implications.  Is it possible that Darwin’s concepts were, as the case may be, too difficult to actually wrap one’s head around?  As can be confirmed by many undergraduates, an understanding of calculus requires much effort and mental contortion in order to become comfortable with its concepts, yet Isaac Newton was able to invent it nearly 150 years before Darwin fully developed his ideas, and was subsequently able to use it to explain planetary orbits.  Could mere difficulty of subject matter, then, be a sufficient impediment to understanding Darwin’s theory?  It is difficult to conceive that that may be the case, since a good understanding of natural selection consists of only, as Stephen Gould has put it, “three facts that no one can deny, and an almost syllogistic inference.”  No, clearly it does not take an impressive intellect to grapple with Darwin’s concepts, at least in a purely ‘bare-bones’ sense.  It seems that there were other, perhaps more deeply entrenched and less obvious worldviews that needed to be overcome in order to pave the way toward an understanding of Darwin’s concepts.

Teleology, or the concept of a goal-oriented nature, was deeply embedded not only in the realm of religious thought, but also etched bias into the annals of scientific thought as well.  Clearly originating from the religious idea of a Devine plan, pre-Darwinian teleologists (K. E. Von Baer, L. Agassiz, Lamarck, etc.) held that the orderliness of the universe was ample evidence of a pre-conceived arrangement, and that this arrangement is what we perceive as the universal laws of nature.  Such a goal-oriented view of the universe led the pre-Darwinian evolutionist and modern textbook punching bag, Jean-Baptiste Lamarck, to conceive a version of evolution that resembled not a bushy tree with splitting lineages, but a lawn of spontaneously generated “blades of grass” as Donald Prothero has put it so succinctly.  Each blade of grass, in Lamarck’s view, represented a new lineage, originating as amoebas, and slowly climbing up the evolutionary ladder (scala naturae) until reaching the highest rung, where man has so willingly placed himself.  Man has never been too keen on self-demotion, and it is precisely this view of anthropocentric goal-orientedness that stood in the way of an entirely naturalistic explanation of biological complexity.  Teleological thinking is still painfully evident today in common misconceptions of evolution.  Indeed, the whole concept of a ‘missing link’ in the fossil record is the result of thinking of nature as a ladder instead of a bushy tree.  Natural selection, in Lamarck’s teleological system, could play no accumulative role since all evolution was internally generated (orthogenetic), and not environmentally driven.  Though early evolutionary ideas were profoundly wrong in terms of evolutionary mechanisms, most biologists of the immediate pre-Darwinian era found it increasingly difficult to deny that modern animals appear to have evolved from previous forms no longer extant.  While orthogenetic evolution can be seen as a severe impediment to early evolutionary thought, mechanistically speaking, there is another mental hurdle that needed to be overcome before the intellectual environment would be fertile enough for the theory of evolution by natural selection to come to fruition.

What was so special about the mid-19th century that resulted in two naturalists, Charles Darwin and Alfred Russell Wallace, to independently discover evolution by natural selection for the first time in human history?  Frequently shown in the history of science are certain intellectual climates where ideas are essentially ripe for the picking.  It is not some vitalistic, or telepathic force that leads two minds to independently converge on an idea, or even the particular caliber of the mind itself, but rather the historical contingency of an ever-growing intellectual milieu that helps synthesize disparate trains of thought, which aids in putting the larger picture into focus.  This is not to suggest that Darwin and Wallace were not men of high intellectual prowess, they were undoubtedly so, but sometimes the intellectual playing field gets super-saturated, and good ideas are bound to find structure and crystallize.  Darwin and Wallace, for example, are known to have read Thomas Malthus’ Essay on Population, which gave them the inkling of the struggle for existence that results when resources remain constant, or rise linearly, while populations tend toward exponential increase.  “The power of population is indefinitely greater than the power in the earth to produce subsistence for man” (Malthus, 1798).  Darwin and Wallace are thought to have also gained great insight from Adam Smith’s concept of an ‘invisible hand’, or the guiding force of what can be called ‘spontaneous orders’ that result from the interplay of individuals acting for their own personal gain.  Smith writes in his Wealth of Nations, 1776:

It is not from the benevolence of the butcher, the brewer, or the baker that we expect our dinner, but from their regard to their own self-interest. We address ourselves, not to their humanity but to their self-love, and never talk to them of our own necessities but of their advantages.

Darwin and Wallace

If Darwin and Wallace had not discovered evolution by natural selection when they did, it is widely believed that it wouldn’t have been long before someone else did.  But why was this new way of thinking; that is, thinking in terms of populations and struggle, such a new concept?  It seems that there was an old and powerful orthodoxy at work here.  Again, this was an orthodoxy that was religiously motivated and ultimately owes its origins to the idea of Creation, and Platonic essences.

Humans and animals, to many in the world even today, represent timeless forms whose existence was foreordained by an ultimately powerful and benevolent Creator.  The idea of Platonic essences (which we will come to shortly) helped buttress this idea of Creation, within the minds of many devoutly religious, as an explanation for the variety of form we see within a species, or ‘kind’ as they thought of them in those times.  If God had created every form of life in the beginning, and these creatures were supposed to be perfectly designed, how does one explain the slight differences that are undeniably observed from one individual to the next?  Nowhere is this more obvious than in our ability to recognize and differentiate one of our friends from the other, or the even greater differences that are observed across cultures.  But how does this idea of perfect Creation harmonize with what we observe in this world?  This is where the idea of a Platonic essence found strong support through the ages.

Many are familiar with Plato’s Allegory of the Cave, where people are envisioned spending their entire lives chained to the floor, facing a cave wall, with a fire blazing behind them.  These people see shadows projected on the cave wall by things passing in font of the fire far behind them.  What is the nature of these shadowy forms to these poor shackled individuals?  Unable to even perceive the true nature of what must be going on, these confused people misidentify these shadows as the final and true thing in and of itself.  But, from our vantage point, we identify these shadows as only two dimensional, colorless essences of the real objects they represent.  It is this idea of an essence, a stripped and distorted version of what is actual, that has fettered the minds of the past from understanding the true nature of biological systems.  Indeed, this essentialist thinking was applied to the animal kingdom, where animals themselves were envisioned as the shadows of some true archetypal form, or the essences of ideas in the mind of God.  One may see many individual cats in this system, each with its own slight variation, be it color scheme, size, or number of whiskers, but these are only deviations from the true essence of catness, which exists only in thought.  It is clear to see that if one truly believes that animals are only shadows of a true idealized form, there can be no true evolution, because a species would be unable to deviate far from its archetypal form.  Natural selection, then, can act only negatively, doing away with those forms that have strayed too far from what it represents.  Death of individuals would have no affect on the future of a species, since each new birth could only diverge slightly from a timeless essence, set in stone since the beginning.  This kind of thinking, whether or not any one person overtly recognized it, played a restrictive role in the intellectual climate, creating much tumult in the seas of evolutionary thought.  This made it difficult for evolutionary theorists to conceptualize the role that this variation actually played in the larger scheme of things.  In doing away with essentialist thinking, the variation throughout a population could then be thought of as new material thrown up for natural selection, an invisible hand that creates innovation amidst chaos, and a truly creative force not held back by some idealized biological cookie-cutter.

So, where do we go from here?  We have seen how the strong biases of teleological and essentialist thinking had been such an obstruction to the new forehead-smacking-obviousness of modern theories.  But have we managed to push all of our mental handicaps to the side, opening the floodgates for newer, deeper insight about the true nature of the world?  Certainly we have in many ways, but the thing with conceptual shackles, especially as it relates to the collective biases of entire cultures, is that, in most instances, you’re only able to point to those impediments once you’ve shed them.  It is easy for us to look back and scoff at the obvious flaws of the past.  I suspect that future generations will look back at us in the same manner, rolling their eyes in disbelief at what we so unknowingly overlooked.  But this almost certain future ridicule shouldn’t discourage us, it should embolden us.  Such hindsight is only attained through a continuous chain of hard-working individuals united toward a common goal—understanding the nature of the world around us.  One of the great rewards for such a work ethic, despite the hear-and-now benefits of new technology, is that every new generation gets to look back and laugh at ignorance long past.  May our descendants oblige us with their mockery!

References:

Gould, Stephen. The Structure of Evolutionary Theory. Cambridge: Belknap, 2002.

Malthus, T. R. An Essay on the Principle of Population. Oxford World’s Classics. New York: Oxford UP, 1993.

Mayr, Ernst. The Growth of Biological Thought: Diversity, Evolution, and Inheritance.  London: Belknap, 2003.

–. Toward a New Philosophy of Biology. London: Belknap, 1988.

Prothero, Donald. Evolution: What the Fossils Say and Why It Matters. New York: Columbia UP, 2007.

Smith, Adam. Wealth of Nations. Found quotes online.

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Posted in: Science