Monday, April 5, 2010

The Evolution of Evolutionary Thought: Why Historians Analyze Evolutionists But Not Evolution

One of the reasons evolutionists are convinced their theory is true is because of the way the species compare to each other. The patterns we find amongst the species, say the evolutionists, prove Darwin’s idea beyond a shadow of a doubt. Such arguments pervade the evolution genre—from textbooks to popular literature—but what exactly do they mean? To understand this we must understand the evolutionary mind. These arguments have circuitous histories and baked-in assumptions that are now long forgotten. But they are worth remembering. Here is one example.

In the early years of modern science it was argued that motion was caused by contact between masses. In this mechanical philosophy, influences in the natural world were assumed to be transmitted only by direct mechanical contact. And while this may seem intuitive, the related assumption that there can be no vacuum was less obvious. But it was taken to be a fact. As Rene Descartes wrote in 1644, “some make the mistake of imagining [the heavens] to be a totally empty space … there can be no such vacuum in nature.”

For Descartes the planets moved around the sun because they floated in a cosmic whirlpool. And although Isaac Newton later disproved any such Cartesian whirlpool effect, the Lutheran philosopher and mathematician Gottfried Leibniz later promoted Descartes’ ideas. As Leibniz explained in 1715, the principle of plenitude disproves the existence of vacuums in nature:

Now let us fancy a space wholly empty. God could have placed some matter in it without derogating in any respect from all other things. Therefore he has actually placed some matter in that space; therefore there is no space wholly empty; therefore all is full.

It was a good example of how rationalism can produce certainty in even the most obscure notions. Empirical evidence gives one a healthy respect for nature’s complexities, but thought experiments lead to tidy conclusions.

Not surprisingly this mechanical philosophy objected to Newton’s idea that gravitational attraction acted at a distance, and even through a vacuum. How could Newton, Leibniz asked, “have the sun to attract the globe of the earth through an empty space?” Such a notion, Leibniz objected, took on occult qualities.

Another theological objection was that Newton’s solar system was, ultimately, not stable. Over eons to time it could occasionally become chaotic. While Newton allowed that God could fix things when needed, this was unacceptable to the rationalists. God was not an unskilled designer who would create a faulty machine. Therefore God would not use miracles to fix nature, and whoever thinks otherwise, Leibniz said, “must have a very mean notion of the wisdom and power of God.”

Despite the many theological objections Newton’s new physics was compelling. But as Newton cautioned, while it explained the motion we observe, it did not explain the origin of that motion. Newton could explain how the planets moved, but not how they got going. That question was attempted by a series of brilliant thinkers in the eighteenth century.

In 1734 Daniel Bernoulli wrote an award winning paper on the origin of the solar system. His explanation, that the sun’s atmosphere caused the planetary motions and alignments, was reminiscent of Descartes’ whirlpools. And while Bernoulli’s explanation was eventually discarded, he introduced a powerful argument that became crucial in evolutionary thought and remains pervasive today.

The planetary orbits were aligned so as to form a striking pattern. Surely this could not have arisen by chance, argued the great mathematician. Bernoulli posited random design as the null hypothesis. Either the planets fell into their orbits by chance or some mechanism caused their alignment. Bernoulli used a calculation to show the long odds of random design, thus proving beyond a shadow of a doubt that a mechanical cause did the job. He who would deny this, the Christian argued, “must reject all the truths, which we know by induction.”

Twenty years later Immanuel Kant elaborated Bernoulli’s argument. Why do planets revolve about the sun in the same direction? “It is clear,” explained the great philosopher, “that there is no reason why the celestial bodies must organize their orbits in one single direction.” If God had directly arranged their orbits then we would expect them to reveal deviations and differences:

Thus, God’s choice, not having the slightest motive for tying them to one single arrangement, would reveal itself with a greater freedom in all sorts of deviations and differences.

Theology was not discarded in the Enlightenment, as is often said, it was internalized. Buffon and Laplace followed with their versions of Bernoulli’s random design null hypothesis calculation, and cosmic evolution became accepted fact. The details were yet to be worked out, but it was a fact. Sound familiar?

Not surprisingly Bernoulli’s random design null hypothesis became a key argument in Darwin’s new theory of biological evolution. For like the planets, the species show striking patterns. Over and over, they are “aligned.” As Darwin pointed out, “We never find the bones of the arm and forearm, or of the thigh and leg, transposed.” If God created the species, the evolution inventor pointed out, then we should find “a sudden leap from structure to structure?”

Such rationalism was rampant in Darwin’s thought, and it is pervasive in the literature today. Biological patterns, and there are many, disprove creation and therefore prove evolution. Mark Ridley, in his textbook Evolution, explains to the student that protein comparisons between 11 different species should not reveal the patterns we find if they did not evolve:

If the 11 species had independent origins, there is no reason why their [traits] should be correlated.

This is nothing more than seventeenth century rationalism in the guise of twentieth century molecular biology.

This is but one example of the many metaphysical arguments motivating and mandating evolution. Why don’t the historians explain this, you might wonder. The answer, it seems, is that historians allow themselves to analyze the evolutionists, but not their arguments—at least not from a theory-neutral perspective.

One helpful exception is Neal Gillespie’s Charles Darwin and the Problem of Creation. Gillespie reveals many of Darwin’s metaphysical arguments, and he explores their context to a limited extent. But the Enlightenment and earlier influences, and the place and importance of metaphysics in today’s theory, are outside the scope of Gillespie’s fine work. And of course those subjects would have raised awkward questions about the theory’s scientific status—and that is not allowed.


  1. Just for fun.

    Descartes, the planets move about the Sun in a whirlpool

    Turns out they formed from a 'whirlpool' due to the gravitational collapse.

    Leibniz, God would not make a vacuum.

    Clearly a metaphysical argument, but then again, it turns out the vacuum is full of virtual particles.

    Bernoulli, Whirlpool effect aligns planets.

    The historical result of the primordial 'whirlpool'.

    Kant, God not restricted.

    Metaphysical, but consider that while a designer is not constrained, the collapse of a nebula will naturally pancake. A designer becomes superfluous.

    Laplace, Nebular Hypothesis

    As we can observe nebula in various stages of collapse, including planets orbiting other stars, the hypothesis can be considered confirmed.

  2. Cornelius Hunter: This is but one example of the many metaphysical arguments motivating and mandating evolution.

    Darwin had to respond to Creationist views because they were still prevalent in his time.

    Cornelius Hunter: Biological patterns, and there are many, disprove creation and therefore prove evolution.

    The Theory of Evolution doesn't depend on a single pattern, but on a variety of evidence from many different fields of study. And the Theory makes important empirical predictions.

    (Interestingly, on ID Forums, you will have some IDers saying there is no nested hierarchy, while others who do recognize the pattern can't be bothered to support the notion.)

  3. COrnelius,
    a random distribution is also the null model in statistical hypothesis testing, which is used in everything from clinical trials to agricultural experiments to, yes, evolutionary biology. I know you're a fan of Bayesian statistics (although not very skilled at using them, see the "one-in-a-billion" thread), but would you say that, for example, a test of the effectiveness of a new cancer drug is also metaphysical bc it "contrasts" its effect against a null model?

  4. Yeah, Hunter doesn't realize that his arguments accidentally take down pretty much all of statistical reasoning everywhere. For ANY question it's ALWAYS possible to say "Well, maybe we see this nonrandom arrangement because GodDidIt that way, not because of this hypothesized natural cause." Statistics is religion and it matters.

  5. Some historians of science do try to analyze evolution, but the Scientific Nomenklatura rejects articles covering such analyses.