May 14 2010

Logic and Creationism

I spent my allotted blogging time this morning debating over e-mail with a creationist who professes to be interested in logic. So, for your edification, here is the latest exchange in a point-counter point style.


Me: It is not just my opinion – it is the opinion of the vast majority of the scientific community. The inescapable conclusion is that you are smarter or better informed than 99% of working scientists – it doesn’t mean you are wrong, but that should give you pause.

Duane: You’re correct in the fact that the majority of the scientific community accepts what you believe as well. But there are explanations for that phenomenon. Besides, I have lived too long and know too much for that to give me pause. We have enough examples in old and new history of the majority being WRONG. I can’t just blindly accept something just because the majority believes it. Galileo comes to mind; how about climate change. We could go back to a whole host of scientific pronouncements about food and health and see it has changed from one side of the spectrum to the other over the years.

Me: There is no example of the scientific community in modern times being completely wrong about a 150 year consensus such as evolution. That would be completely unprecedented. Galileo is not a good analogy – he was not bucking a scientific consensus but religious dogma. Climate change is not a good analogy – the consensus is far more recent, not nearly as solid as evolution, and you cannot assume that it has been rejected or disproved – at the very least this is still controversial. Similar with food and health – I am a physician and very familiar this history and evidence. There is nothing here even remotely similar to evolution.


Duane: By the way, you may have caught yourself before committing the “Majority Rules” or “Might makes right” fallacy, but you are darn close to appealing to the “Ad hominem” argument by denigrating my intelligence. For someone who has dedicated an entire web page to logic you sure like to mingle your arguments with touches of logical fallacies throughout. Insulting me is not helping your argument.

Me: I did not “catch” myself – this is part of the nuance of this logical fallacy. Read my full article on it: And another article just on the difference between authority and consensus:

Further – saying that you are probably not smarter and better informed than 99% of working scientists is no where near an ad hominem.

Secondary Hostile Sources

Me: You are proceeding from false premises because you are grossly misinformed. I don’t know with whom you are talking, but you are either not hearing them correctly or they do not understand or know how to explain the evidence for evolution. I suggest you read a pro-evolution text (rather than just secondary hostile sources) to see what the science really is.

Duane: I have had no choice but to hear, see and read pro-evolution text and so forth…it’s everywhere. It’s taught in our public schools, colleges, and universities. It’s on every TV program that ever talks about nature. There’s a gazillion books on the subject. Come on dude, I don’t live under a rock. Perhaps your right, the people I have spoken to, and there have been many, weren’t very good at explaining macro evolution, but I have been asking for evidence from someone, anyone, who can give an intelligent argument without arguing from logical fallacies for twenty-one years. I am opened minded (not so opened mined that my brains will fall out) so perhaps you’re the one guy who can pull it off.

I have heard a tremendous amount from evolutionists. Maybe you need to be more fair minded and unbiased and listen to some of the more intelligent creationists who happen to be scientists. Not that one has to be a scientist to know truth from error on the subject. I can recommend some reading if you like.

By the way, “…to see what the science really is.” Wow this is a really presumptuous statement from you. All due respect, I think it would behoove you to go back to the basics of science and understand what the SCOPE of science is. PROVING our origins is beyond the scope of science. We weren’t there to witness it and we cannot duplicate it. Science works on observation and repeatability. The best that science can do on the subject of origins is to give a reasonable scientific theory, not a pronouncement of scientific fact. Another thing that people never acknowledge is how often bias is introduced into the information gathering and conclusions drawn by certain data. Again you can look at many cases of that over the years. In other words scientists are human and can make mistakes or even try to fudge the data to fit their presuppositions. You shouldn’t put any group of human beings on too large of a pedestal.

Me: There was nothing presumptuous in my statement at all. You stated bold misrepresentations of the science, which are in line with creationist talking points. I did not have to presume anything – it is obvious you do not have an adequate understanding of the evidence for evolution, or the nature of science.

For example, you repeat the creationist canard that a scientific theory cannot also be an established scientific fact. This is not about metaphysical “proof” – scientists are very clear about that. There is no absolute proof in science. The fact that no one was there to witness evolution happen is another canard – science is not dependent upon direct observation of events – to think that is to dismiss all historical sciences. Science can use logical inference and test hypotheses about what happened in the past. Evolution makes many specific and testable predictions – and so far all of those predictions have been validated. Evolution has been confirmed to such a high degree that we can now take it as a solid premise – an established fact.

Regarding bias, of course it is rampant in any human endeavor. But science is also self-corrective, and bias is systematically worked out. Also, the point of consensus is that individual biases are averaged out over many people – that is precisely why a consensus of many is more compelling than the quirky beliefs of an individual. I don’t put scientists on pedestals – I trust in the process of science because it works.


Me: Right off the bat – “There is no evidence what so ever for macro evolution.”
This is demonstrably patently false. You have not been looking or listening. Evolution is not based solely on evidence for “microevolution” (whatever that means) – observed small changes is just one line of evidence, and probably the weakest.

Duane: The burden of proof is on the affirmative. Ex. “Macro evolution is true” not the negative “There is no evidence what so ever for macro evolution”. You are aware of this principle right? It’s the whole reason why in a court of law the burden of proof is on the prosecution and not the defendant. It’s easier to prove the existence of something than the non-existence of something (The latter would require infinite knowledge). Prove it! I’m listening!

Let me define some terms here just so we are on the same page in our understanding. Between the terms micro-evolution and macro-evolution the difference is huge. Micro-evolution is another term for adaptations (As you said above…observed small changes) but the species is still the same species it doesn’t change into a completely different creature. Macro-evolution is the term used to describe a complete change of one species or animal into a completely different species. Of which, as I stated before there is no evidence for what so ever.

Me: I am not asking you to prove that evolution did not happen. But you are making a negative statement – there is no evidence. Those types of statements can be falsified by one counter example. I have, below, presented to you a great deal of evidence for macro evolution, which falsifies your claim.

Regarding “macroevolution” – the reason this is a problematic concept is because the notion of “species” is very fuzzy. You say “completely different species” as if that means something scientifically or quantitatively. In reality species blur into each other with very fuzzy borders. There is no distinction that you can make between evolutionary changes within a species and changing from one species to another. It’s a continuum.

Fossil Evidence

Me: The major lines of evidence for what you call macroevolution, and what scientists call common descent, include the fossil evidence, the nestled hierarchies of gross anatomy, which also fit a temporal and geographic pattern, developmental biology, and (the biggest evidence) the molecular genetic evidence.

Duane: There is no fossil evidence for macro-evolution. Show me and don’t point to adaptive changes in the fossil record and assume, illogically, that because that happened macro-evolution had to have happened. You can explain the middle two theories if you like. I’m interested. As for your so called “biggest evidence” molecular genetics, the opposite is true. Once again there is no evidence for it but evidence that contradicts the macro-evolutionary theory. In fact in this area of science you will see more derision between scientists than in most other disciplines of science because of the evidence against it.

Me: Wow – this one always gets me. There is overwhelming fossil evidence for evolution, specifically common descent. You must have at least some familiarity with the many transitional fossils we have discovered, so by what twist of logic are they not evidence for common descent. Evolutionary theory predicts that we will find fossil evidence of species that lie somewhere morphologically between extant groups – they must be connected in the past if all life descended from a common ancestor. That is a falsifiable prediction made by evolution. And in the past 150 years we have discovered (just to give some recent examples):

Transitional turtles:
fish to tetrapods:
half whales:
transitions from reptile to mammal:
transitional pinnipeds:
Many primates:

This is just off the top of my head. None of these species had to exist if creation were true. Evolution requires that something like them did exist. The fact is, over the last 150 years we have been steadily filling in the tree of life, as predicted by common descent. This has been a stunning scientific confirmation.

Genetic Evidence

Me: The genetic evidence alone leaves no room for doubt that all life on earth descended from a common ancestor.

Duane: I already answered this to some degree in the previous paragraph. But once again the burden of proof is on you. Show me. If you are referring to common features or substances within all of nature…It’s yet another example of a leap of logic to say just because you see common design features or substances doesn’t mean they had to be descended from that species or we all had a common ancestor. These are illegitimate inferences.

Me: Here is a good summary of the evidence for macroevolution – Please read Part 4 at least on the molecular evidence. It is a slam dunk for common descent.

Now your 20 year wait is over. I will be happy to discuss this evidence with you afterward.

Scientific “Law”

Duane: I’ll read it and get back to you. Thanks for the info. By the way, if it is a slam dunk then why is macro-evolution still a theory and not a scientific law? I never did get it when evolutionists make similar claims.

Me: You have not made an argument – you simply made a false assertion. I have provided you with a summary of the evidence – the pattern of proteins, genes, viral inclusions all point to common descent with a statistical power that is staggering. You are simply parroting hostile sources which lie about the evidence.

You also misunderstand what is meant by a “law” in science. A “law” is a fundamental property of the universe. Evolution is historical – it is about what happened in the past. It will never be a law. You also misunderstand what scientists mean by “theory” – a theory is an explanatory system that brings together many observations and makes predictions. It is not a statement about certainty. A theory can also be a fact (like gravity) if it has been sufficiently supported by evidence that we can take it as a premise.

Straw man

Me: Regarding your other point about straw man arguments – this is just not valid. If I say it is a common creationist argument to X – that does not imply that all creationists make that argument, and since not all creationists do it is a straw man. You are really stretching there. I am just giving examples of arguments that represent each fallacy, not fully describing the range of creationist beliefs and arguments.

Duane: You seem to have a double standard. You accused me of the straw man tactic when I used the word “scientists”. You used the word “creationists”. I like you didn’t say ALL scientists but yet you accused me of straw man. I acknowledged out of fairness that it would be construed as such so I clarified myself. I’m merely doing the same as you and giving examples. If I’m stretching you’re stretching as well.

Me: You miss the point. Your argument was a straw man because no scientist makes the argument you stated. There is a difference between “no scientists” and “not every creationist.” Some creationists make the argument I was using as an example, therefore it is not a straw man.

The Challenge

Me: You seem like a smart guy who is truly interested in logic. I do not think you or all creationists are idiots. I think you are just misinformed, by a very deliberate, sophisticated, and well funded campaign of misinformation that has lasted for several generations. What I am asking you to do is just consider the possibility that you don’t have all the information. Perhaps 99% of scientists agree that evolution is an established fact because they have more or better information than you. Ask yourself how much you have relied upon secondary hostile sources for your information, or if the evolutionists you have spoken with were really in a position to properly represent the evidence.

Duane: “very deliberate, sophisticated, and well funded campaign of misinformation that has lasted for several generations.” You sound like someone paranoid and into conspiracies. That is absolutely a ridiculous and an unfounded falsehood. “What I am asking you to do is just consider the possibility that you don’t have all the information.” I can do that and have many times when someone has tried to prove the evolutionary point only to be still left with no evidence. I’m fair…I’ll give you a shot. If you want me to consider I may not have all the facts then you need to consider you may be wrong and also don’t have all the facts. After all it’s beyond the scope of science to prove our origins and you and I nor anyone for that matter has infinite knowledge.

Me: It is not an unfounded falsehood (you know, you just can’t make stuff up whenever you want just to make a point). What do you think the Discovery Institute is – a well funded organization with a specific goal of spreading scientific misinformation to oppose evolution and “materialist” science and promote an ideology of supernaturalism. There was “creation science” before them, and laws to oppose evolution and promote creationism before that. There has been an actual anti-evolution movement in this country for over 100 years. This is history, not paranoia.


Me: Take a look at the molecular evidence with an open mind. If you can think of a viable scientific explanation for that evidence other than common descent I will be very happy to hear it and discuss it with you.

Duane: You need to understand something, I don’t have a problem if someone wants to claim and teach that macro-evolution is a very reasonable theory and explanation of our origins. What I have a problem with is when the majority claims and teaches a scientific THEORY as scientific fact. That’s not what science is about.

Me: I think you misunderstand what we mean by “scientific fact.” That means it is the best theory we have and it is supported by so much evidence that it would be obscene not to give it provisional assent – which is the best science will do. We can proceed as if gravity is real, as if protons and electrons exist, as if DNA is the molecule that carries inherited information. These are all theories – and facts. They are open to fine tuning and modification – but the probability that we will discover that DNA has nothing to do with inheritance is so small we can ignore it. That is what it means to be a scientific fact.

The same is true of evolution, you just don’t know it.

Let us focus on the molecular evidence, otherwise such conversations expand beyond control. I am giving you what I think is the best evidence – I accept the burden of proof. I think it has been met, without question.

The way to approach this evidence is this – nothing metaphysically “proves” evolution – that’s not how science works. But you have to ask yourself – what predictions does evolution make about what we would expect to find when we analyze the DNA of various species. What predictions would creationism make? Are there any other options, and what predictions would they make?

I look forward to your response.


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