the evolving mind

A major quibble? Clearly I am confused. But that is where I must start, though in future posts I will be sharing the many admirable things about Richard Dawkins’ latest book, The Greatest Show on Earth: The Evidence for Evolution. I feel forced into placing my single significant criticism up front, for that is where he, somewhat puzzlingly, places what I consider to be the most contentious point. Up front.

In the preface Dawkins writes:

“This book is my personal summary of the evidence that the ‘theory’ of evolution is actually a fact — as incontrovertible a fact as any in science.”

Wow. Incontrovertible means “absolutely certain and cannot be shown to be wrong.” As any in science. I’m jumping ahead of myself here, but it seems the argument — by those who should really know better — that evolution is indeed a fact is a rhetorical tactic. Evolution is a fact, case closed. If you can’t see the fact, you’re blind. I feel this kind of argument miseducates as much as it might, might, make a valid point. How does it miseducate? Two ways. 1) It stretches the definition of fact too far. 2) It places the emphasis on a conclusion and not on the essential and supremely solid scientific reasoning that gets us there.

Dawkins’ very first chapter is titled, “Only a Theory?” In it he argues that evolution should be considered a fact. Why not present the overwhelming evidence first, thus making the acceptance of the “fact” status more sensible? This ordering seemed illogical to me.

As for the meat to my major quibble, on page 8 Dawkins writes,

“Evolution is a fact. Beyond reasonable doubt, beyond serious doubt, beyond sane, informed, intelligent doubt, beyond doubt evolution is a fact.”

I, for one, am sane and informed but would disagree. And it all hinges upon the definition of fact.

On page 10 Dawkins claims, “Evolution is a fact in the same sense as it is a fact that Paris is in the Northern Hemisphere.” He elsewhere says, “common sense treats it as fact . . . ” Oh c’mon. An appeal to common sense? Really Richard? Appeals to common sense are frequently appeals to out own common assumptions.

Clearly there are different definitions of fact. Dawkins well knows this and gives a nod to it. Later in the chapter, rather than “theory” of evolution, he argues for “theorum” — to give greater heft to the classification of the theory, to separate it from the other riff-raff “theories.” Aha! So words do matter.

In this manner I agree with Dawkins: sometimes we lack suitable words for what we talk about. They can be blunt instruments. As with the word “theory.” The theory of evolution is certainly a different instrument than string theory and, way out on the spectrum, the “theory” that JFK was killed in a government conspiracy. How do we distinguish between a major-league theory and one that comes from so-far out in left field you can barely call it a theory? Important question.

Other words are not so blunt. And I would include “fact” in this category. And yet it seems that Dawkins calls for a softer definition. On page 14 he includes this definition of fact:

“something that has really occurred or is actually the case . . . . a particular truth known by actual observation or authentic testimony, as opposed to what is merely inferred . . . a datum of experience.”

As is the case throughout his fine book, Dawkins makes some very good, important points. Such as the tidbit about courtroom-grade evidence:

“Careful inference can be more reliable than ‘actual observation’, however strongly our intuition protests at admitting it.” (p. 15)

True. Note the half-quotes around “actual observation” however. His analogy wobbles when we consider that the “court” of science is distinctly different, as are the type of observations it typically relies upon or at least aspires to rely upon.

Still, a very important element is the whole notion of inference. In my understanding, things that are factual are verifiable bits of data — not conclusions drawn from bits of data, no matter how solid the data and how impressive the quantity. Where there is any inference drawn between individual factual elements, you have ventured beyond fact.

Similarly, where there is an interpretation of a set of facts, the result is not a greater fact. On page 308, chapter 10, “The Tree of Cousinship,” Dawkins writes:

“Once again, the ‘skeleton’ is invariant, while its parts are anything but. And once again the obvious — I would say the only sensible — interpretation is that all these crustaceans have inherited the plan of their skeleton from a common ancestor.”

The common ancestor part of evolutionary theory surely relies upon interpretation. That, to me, seems to rule it out as fact. A very, very, nearly-fully-beyond-doubt conclusion, yes. But not a fact. The common ancestor element is a major component of evolutionary theory. And yet it relies upon an interpretation of the data. Of what I would call the facts.

In chapter 13, “There is Grandeur in this View of Life,” Dawkins seems to stray even further from his hard “evolution is fact” stance.

“Darwin was right to hedge his bets, but today we are pretty certain that all living creatures on this planet are descended from a single ancestor.” p. 408

Pretty certain? Of a key element of evolutionary theory? To me, a fact is something that is as certain as a human can be certain. Facts are beyond dispute.

To be fair, a jury might only be “pretty certain” of the many pieces of evidence in a murder case placed before them. But the bulk of the evidence can add up to something more. But I would argue that something more adds up to not a fact, but to a “very certain” verdict, a conclusion beyond reasonable doubt.

Okay, enough about my quibble. [And to any potential creationist quote-miners, it is my intellectual integrity that impels me to argue semantics. If you had intellectual integrity you would not steal a tree and call it a forest.]

Evolution is a very sensible, highly likely to be true, explanation of a mountain of rock-solid evidence. Still, it is a theory, an explanation, a model. Not a fact.

Good science relies upon precision. Precision with instruments, including the words we use. Dawkins knows this. But sometimes I think his political self gets in the way. Such as on page 10:

“As for the claim that evolution has never been ‘proved,’ proof is a notion that scientists have been intimidated into mistrusting.”

There is good reason why scientists shy away from proved. It is a word suited for absolute certainty. It belongs in the domain of mathematical equations, for one. But because scientists understand the significantly provisional nature of our knowledge, to use the word “proved” where absolute certainty is lacking, is an exercise in arrogance.

While I consider it ludicrous to reject the theory of evolution, I find it fully sensible to question whether we can call it a fact without stretching the definition of fact beyond the sensible.

Okay, I’ve voiced my reservation about Dawkins’ otherwise fantastic book. In subsequent posts I’ll address what I believe Dawkins got right.

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