What's So Bad About a Good Theory, Anyway?
Evolution is a theory, not a fact!
That has got to be one of the top ten most ignorant things coming out of the Christian Right these days (I know, it's so tough to choose, but I'm pretty sure on this one). I've always found it remarkable that so many people could repeat such drivel so many times without getting sick of listening to themselves. This particular bit of tired wisdom betrays a profound lack of scientific understanding: theories are marvelous things! Anyway, I'll let David Quammen, of National Geographic, take it from here:
Evolution by natural selection, the central concept of the life's work of Charles Darwin, is a theory. It's a theory about the origin of adaptation, complexity, and diversity among Earth's living creatures. If you are skeptical by nature, unfamiliar with the terminology of science, and unaware of the overwhelming evidence, you might even be tempted to say that it's "just" a theory. In the same sense, relativity as described by Albert Einstein is "just" a theory. The notion that Earth orbits around the sun rather than vice versa, offered by Copernicus in 1543, is a theory. Continental drift is a theory. The existence, structure, and dynamics of atoms? Atomic theory. Even electricity is a theoretical construct, involving electrons, which are tiny units of charged mass that no one has ever seen. Each of these theories is an explanation that has been confirmed to such a degree, by observation and experiment, that knowledgeable experts accept it as fact. That's what scientists mean when they talk about a theory: not a dreamy and unreliable speculation, but an explanatory statement that fits the evidence. They embrace such an explanation confidently but provisionally—taking it as their best available view of reality, at least until some severely conflicting data or some better explanation might come along.
So next time your local Dr. Dobson tells you that Evolution is just a theory,
tell him that he's just an ignorant ape!
posted by Penguin One at 9:36 PM
2 Comments:
If you are arguing that theory is the same thing as fact, I am not sure I am convinced. Scientist are in the business of postulating a logical explanation for the unknown. In the process, theories are introduced as possible explanations. Theories rely on evidence that may not represent the whole picture.
For example, before scientists theorized that the sun was the center of our solar system, they first theorized that the earth was the center. There was logical evidence to support this theory. As more evidence was discovered, the theory was replaced with another theory that the sun is at the center of the solar system.
For another example of scientific theory that was proven wrong, take an essay from the book "The Trouble With Testosterone: And Other Essays On The Biology Of The Human Predicament" by Robert M. Sapolsky. The essay to which I refer is called 'Poverty's Remains.' In the past, medical doctor's had to rely on cadavars for furthering the understanding of the human body. The cadavars that were donated to science were almost exclusively donated by the poor or turned over to science by the state when someone had no family to pay for burial fees. As a result, physicians came to accpet that a certain gland in babies was normally of a certain size. The problem was that the babies they were inspecting were malnourished. The glands they saw a sample of were abnormally small. When healthy babies were examined, doctor's attributed a larger gland (which was actually a healty sized gland) to be a possible cause of SIDS. Healthy babies were operated on and their healthy glands were removed to prevent SIDS. Instead of preventing SIDS, these babies had very high mortaility rates because their healthy glands were removed. Once doctors figured out their error, the surgical procedures stopped, but not before hundreds of otherwise healthy babies perished. The doctors were not making ill-assumptions. And the theory about the size of the gland was rooted in logic. The problem was, the theory was rooted in a logical explantion to evidence that represented a sub-set of the big picture without even realizing their error.
So there is a difference between fact and theory. And what may be a widely accepted theory today, may be debunked as new information is uncovered tomorrow.
Yes, that's very well stated. A theory is not a fact. The ignorance that I'm pointing out is the implication that somehow the theory of evolution by means of natural selection is lacking some validity because it is not a fact. The theory of evolution can never be a fact: it is an explanation of the world around us. But, I do think the facts of evolution (e.g., allele change over time) strongly support the theory of evolution (that the distribution of allele changes over time is largely driven by natural selection).
Thanks for the comment. I should have been more clear about my intent in the original post.
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