How to defend evolution

Whoop de crap. And they don’t dominate the planet, we are doing more to change it than they are. Plus, someone must study them, so they do effect people, and someone might find something useful to make out of them (just because no one has yet doesn’t mean they won’t). And they affected you, since you had to bring them up in your post, they’ve influenced your thought processes.


The whole “Intelligent Design” movement, besides an attempt to repackage Creationism in yet another marketing campaign designed to get the thin edge of the wedge into classroom, is an attempt to argue by definition.

To them, the idea of “irreducable complexity” is a given. To most people it’s just stupid. An ID person will typically argue something like this: “The eye is so exquisitely designed that if you take away any of the parts it would cease to function”. Yes that’s true. But then, eyes aren’t manufactured with parts like a camera (or a watch, since, hell, we are talking about a retread of Paley’s Argument from Design anyway). To talk about an eye being “irreducably complex” in an individual ignores the fact that individuals don’t evolve; populations do. And you don’t have to look far to see populations where a light sensitive spot is better than no light sensitive spot, where a eye pit is better than none, where a pinhole eye is better than a pit and a lensed eye is better than most.

Of course, in humans our “irreducably complex” “designed” eyes have the light sensitive cells facing ass backwards necessitating a blind spot, but no matter.

I haven’t seen anyone else mention this, but the premier slayer of Intelligent Design is the British Zoologist Richard Dawkins, whose book “Climbing Mount Improbable” and “The Blind Watchmaker” contain arguments and examples that when presented to an ID person may not sway them, but it will probably make them stick their fingers in their ears and hum.

Rev wrote:

I don’t think they use the eye as one of their examples, do they? But even if they do, I don’t quite get your point. I thought that the point of irreducible complexity theory was to show evidence of mediation in an organ or organism.

Science is based on empirical observation. It does not posit that the universe is consistent in it’s adherence to certain laws, it observes that it is. The same cannot be said of religion.

What does that mean, science is “based” on empirical observation? Empirical observation is one tool of science, but science is based on the principle of falsification.

Actually, what I really hate most in the ultra-repetitive creationism vs evolution argument, is the fact that Creationists are usurping the phrase “Intelligent Design” to equate it directly with “Fundamentalist Christian Literalism”.

It is as if the damn southern Baptists are trying to eradicate all mention of Divnity throughout the world, unless it has their particular Protestant tag on it.

Darn annoying.

I totally agree with Robert on this point…I have always considered science to be something of a religion of its own…one that I subscribe to, mind you, but I have never equated science with “truth” necessarily. Just a useful way of trying to understand the world.

Having said that, I think the OP’s friend misunderstands the development of the reproductive systems. Original life forms did not need “reproductive systems” per se, they engaged in mitosis and divided themselves up. Some of these creatures might eventually have begun exchanging DNA between each other, but even this would not require much of a “reproductive system” at the monocellular level. From that point, things gradually progress until you get multicellular organisms which begin developing specific reproductive systems to enhance their odds of success.

I fear it sounds like your friend might lack even the sort of rudimentary understanding of biological systems, and that lack of knowledge may make it difficult to convince him. Try convincing your dog that he/she is a product of evolution and give him/her a quiz on what you tell them.

Avalongod wrote:

That was well said. Science cannot tell us what is true, but only what is false. If it gave us truth, then its hypotheses could not change.

The first thing to do is to ask your ID friend what he thinks evolution says. It sounds like his model is a single organism mutates sufficiently to become a new species in one jump. Actually, whole isolated populations drift into reproductive isolation slowly. Look up “ring species” in As one example, consider horses and donkeys. They have offspring (mules) almost always sterile. They’re clearly in the process of diverging, in another million years or so no doubt they won’t be inter-fertile at all. Yet horses produce horses and donkeys produce donkeys.

I don’t understand, actually, what this has to do with ID. IDers mostly accept speciation, and only claim certain specific mechanisms must be designed. (Actually it is pretty fuzzy what IDers really believe.) They don’t actually stress this, since their only real backers are creationists who would not be happy to hear them accept a very old Earth. So your friend sounds more like a creationist than an IDer.

You can also ask him to explain, in his own words, the concepts of mosaic evolution and exaptation, since these are key concepts in explaining the evolution of many complex systems.

Lib, I don’t think I could have worded it any more clearly. What exactly don’t you understand about my statement?

Falsification is part of the methodology of science. How does that indicate that science is not based on observation? That’s like saying “My car has wheels, therefore it is not powered by an internal combustion engine”.


They may not use the eye as an example anymore, although they have in the past. You know, the sort of people that will quote Darwin’s difficulty in explaining the evolution of the eye without quoting the rest of the chapter. If they have given up using the eye as an example it is just because folks like Dawkins have humiliated them on the issue. They will just move to some other organ or wait a period of time and then use it again. Somewhere out there Duane Gish is still blathering about the bombadier beetle, but I hope ID folks are more honest than your average polyester clad Creationist. I’m not holding my breath.

Actually the point of irreducable complexity is pretty tautological, intended to show that some structure or physiological process, because of the integration of parts, had to arise all at once. In other words, you just ignore evolutionary processes, assume that everything had to arise fully formed and voila, you get an intelligent designer.

The similarity between ID and Classical Creationism is that the ID folks are not trying to persuade scientists and people most knowledgeable about these things. They are either preaching to the choir, the legislature or to the school boards.


I see. Thanks for that clarification.


Falsification is what distinguishes science from pseudo-science.

Pseudo-science is like a tautology — it is proved by everything under the sun. Every empirical observation is perceived to fit the pseudo-scientific hypothesis. Take Freudianism, for example. There is nothing a Freudian can observe that he cannot explain by childhood trauma or penis envy. Same with astrology. And for that matter, creationism. All those pseudo-sciences see all data as confirming their theories.

But genuine science doesn’t work that way. It forms hypotheses that risk being false. Then, it uses empricism and other methods to test them. To be scientific, a hypothesis must be falsifiable. You can’t falsify a hypothesis that says God created Adam and Eve. In fact, you can’t falsify any hypothesis about metaphysics.

As I said to Avalongod, science tells us only what is false, not what is true. If it told us what is true, then our hypotheses could not change. Rigid and doctrinaire hypotheses are the very antithesis of science. Science is designed to alter its hypotheses when they are found to be false. It is not designed to declare a final truth.

See this excerpt from Popper’s * Conjectures and Refutations*.

Agreed, and I am glad you brought Karl Popper into this. You’ve put this much better than I could have. I would go a step further and note that science can be a bit dogmatic at times…its not always as quick to change those hypotheses as it should be. But generally things work out the way they should.


I think you raise good points, but as a scientist (in training), I find that most other scientists are not concerned so much about “truth” or “proving a theory.” We design experiments to support hypotheses and theories, but books are very rarely, if ever, closed.

We have a system, and it works. Granted, religions are systems, and to the faithful they work as well. But scientists have a leg up – the power of prediction which we can demonstrate works.

To the OP’s respone:

First, single celled organisms evolve all the time – antibiotic resistance, ways to evade the immune system, the ability to live in new places, etc. Second, bacteria and other single celled organisms sexually reproduce quite actively. Bacteria like E. coli swap parts of their genome quite regularly. In addition, there are bacteriophage (viruses) which swap bits of genome in a process called transduction. This works not only within a species, but between species as well – this is called lateral transmission. There are examples of lateral transmission even in humans. Lastly, they don’t need these things to evolve – they do just fine with regular old mutational mechanisms.

For the 10 to the power of 40,000 thing, it is important to understand the idea of selection. Let’s say I want to pick the winning lottery number. But instead of picking 6 numbers from 1-50 at random, I pick 6 and they tell me if any are right. I can then continue to pick new numbers until I get the right numbers. This is kind of how natural selection works in evolution. Things are very complex, but they are not assembled at random. They are assembled step by step over millions of years, and only the pieces which fit right are passed from generation to generation. Bad parts get tossed.

This is besides the anthropic principle – we only get to see the winning results because if they weren’t winning, we wouldn’t be around to see them. This, combined with the power of selection and the billions of individual trials that have occurred during the evolution of life, is quite adequate to explain it all.

You’ve repeated this before… and you’re still wrong.

If science is telling us that a particular hypothesis is false, it is telling us a truth. What science cannot do is tell us everything that’s false. If it did that, then its hypotheses couldn’t change.

Science can tell us things that are true, not the entirety of the truth.

Science deals with probabilities, not truth. That’s something a lot of people have never understood.

Good point.

Although I think the probability of science’s being wrong on certain matters to be so low that, for all intents and purposes, they’re facts.

I’m confused as to why you are presenting this as if it is contrary to my position. I happen to agree with you. Please note that I never said empirical observation is the totality of science. I merely said it was based on it.

A hypothesis does not come out of thin air. A scientist first observes some aspect of the universe., then forms a hypothesis.

And how do we falsify a hypothesis? By empirical observation. When the data do not fit the hypothesis, it is revised or discarded. This differs from religion, which tends to espouse dogma which is accepted on faith alone.

Again, I pretty much agree. Why are you purporting to disagree with me?

Heck if I know. My apologies.