Now, with the introduction out of the way, I will continue by examining what Gärdeborn presented as, in his view, solid scientific arguments against evolution. I have, as far as possible, tried to formulate my text without giving Gärdeborn too much credit for them as these are in no way new arguments, nor are they his. They have been for a long time, and they continue to be, part of the general creationist discourse.
For the sake of order, I have grouped them roughly under the headings "the structured universe", "the 'devolution' of nature", "evolution 'within kinds'" and "biological information". I had planned on examining all four of them in one post, but since I want to be quite meticulous and I'm busy working on a shorter print version of this essay in Swedish, I'm choosing to publish the first two in advance.
The structured universe
The first supposedly scientific argument is hilariously outdated. Gärdeborn formulated it something like - "the universe is finely calibrated and full of complex structure, ergo it has to have an intelligent designer behind it!" We know that this is nothing but the old fallacious argument from incredulity, but it's worth examining it a bit further with regard to this apparent "structure" he was talking about. The word "structure" in this case being used instead of the one chiefly used by creationists - design. "If there is a design, there must be a designer!"
This cognitive fallacy can be beautifully illustrated by the well-known and often quoted anecdote involving philosopher Ludwig Wittgenstein:
W. and his companion are on a stroll through Cambridge.
"Tell me", says W., "why do people always say it was natural for man to assume that the Sun went round the Earth rather than that the Earth was rotating [around the sun]?"
"Why?" said his surprised interlocutor, "well, obviously, because it just looks as though the Sun is going round the Earth."
"Hmm", retorted W., "well, what would it have looked like if it had looked as though the Earth was rotating [around the sun]?"
In our particular situation Wittgenstein might just as well have asked, "what would the universe have looked like if it had looked as though it had no structure?" The answer is the same: it would have looked no different.
Some logical fallacies are errors of perspective. The way something appears to us can be regarded as a property of that something we are observing; we automatically assume this in practically everything we do. But this property, the way it appears, is also interesting in itself because it reflects an implicit property of that to which it appears, us. In other words we might say that the universe looks as though it's organized and structured simply because we are looking for organization and structure in the universe. It's the method our brains use to describe our surroundings to us in a way that we can find useful. The fact that we have a penchant for observing structures and patterns in the biological world is a reflection of us, not it. It's a bias in our thinking which is also inevitably mirrored in our language. Even the most experienced and senior scientist might express wonder at the structure of that which he or she is studying, but a scientist realizes that this structure, this purposeful organization, is only apparent. Our brains and in extension our language and preferred choice of words might deceive and mislead us more than we usually are able to acknowledge.
I can only say that it's unfortunate that Gärdeborn did not read up a little more on the basics of cognitive neuroscience before embarrassing himself by falling into such an easily avoidable fault.
The "devolution" of nature
While still on the subject of structure, Gärdeborn misrepresents evolution as a linear process through which "things with structure develop from things with less structure." This is a totally unfounded oversimplification. Deviously, creationists only use it because it serves their purpose. It's a classical straw man - they misrepresent their opponent's position so that it's easier to refute. But as it turns out, even this misrepresentation is not an easy one to counter.
While evolutionary processes have indeed increased the complexity of organisms over evolutionary time, this is in no way an intrinsic property of evolution itself. In fact, evolution has decreased complexity many times. One of the most poignant examples being parasitic organisms, many of which have lost structures and functions in comparison with their free-living counterparts. The parasitic bacteria in the genus Mycoplasma, for example, have lost their external cell walls as well as most of their metabolic pathways as a part in their adaptation to the highly specialized conditions within their hosts. This is seen in their genomes; Mycoplasmas have some of the smallest ones observed in any organism.
At the core of this misleading definition of evolution is then a serious problem. In order to affirm that evolution goes from less structure (or lower complexity) to more structure (or higher complexity) you have to suppose that evolution has a predestined goal. But not only that; as a result of this false assumption you would have to suppose that organisms which exhibit less complexity are less evolved. Of course no biologist would ever suppose this, it's not only the greatest but also the most easily avoidable fallacy you can make in evolutionary thought, as any good high-school biology textbook will tell you. Yet this is what Gärdeborn proclaims evolutionary scientists do. What poor understanding.
The reason it's so common to ascribe goal and intention to evolutionary processes is simply that we have a hard time describing or understanding evolution in other terms. This is another way in which our language misleads us. Within the world of research, we all of course know what we really mean to say.
What is Gärdeborn getting at then? What purpose does this flawed definition of evolution serve? This is the old "second-law-of-thermodynamics-argument" against evolution, maybe the silliest and most simple-minded argument creationists have ever used. The argument owes its recent revival to mathematician and intelligent design proponent Granville Sewell who, in the beginning of the decade, published a couple of articles on the matter. Articles that have subsequently been panned by serious biologists, physicists and mathematicians alike.
The second law of thermodynamics states, in one of its simplified forms, that natural processes in a system only can lead to the increase in the entropy of the system. Entropy being a sort of measure of "disorder" or lack of complexity. "But wait a minute now! How can evolution then increase the complexity of living organisms!? Wouldn't that decrease the entropy?" Believe it or not, that is the entire argument. Since nobody doubts the veracity of the second law, it must be evolution that is false.
I've already established that evolution does not necessarily lead to organisms with higher complexity than their ancestors. But even if we assumed that it always does, the second law of thermodynamics is only valid for closed systems. Earth imports energy from the sun and thus contributes to the total entropy of the universe. In the same way, organisms import energy in order to sustain themselves, decreasing their own local entropy, but at the same time contribute to the increase in the total entropy of their surroundings. Neither earth nor living organisms are closed systems.
The way creationists usually respond to this fact is by invoking the argument from incredulity again, saying that the fact that organisms can import energy, and thus supposedly "break" the second law, is so unlikely that it simply must mirror an purposeful design. This in fact makes the "second-law-of-thermodynamics-argument" a non-argument. As comically ridiculous as it is, creationists are still using it.
Aside from the fact that it negatesitself, it's a particularly bad argument because it's merely a rhetorical one, not a scientific one. By appealing to our "common sense" and our own observations of nature, and not least to our cognitive bias towards structure and purposefulness, creationists try to win us over. "Surely", they'll say, "you must notice that in nature everything has a tendency to break down, not to be built up, as evolutionists tell you. Nature devolves, it doesn't evolve." It's devious, it's misguided and it's not science. The second law is not about probabilities or common sense, it's about thermodynamics and entropy. Creationists can either produce an entropy calculation showing that evolution breaks the second law, which is impossible, or they can shut up. That's my modest advice.
Edited February 21. Thanks to SK for pointing out an error.
Swedish blog tags: Vetenskap, Evolution, Biologi, Pseudovetenskap, Kreationism
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