Well, to be honest, in all of my reading on the topic (which has included books written specifically to criticize creationism and books written specifically to popularize evolution and visits to the Chicago Field Museum) I have never encountered a single attempt to prove that the theory of evolution is true.
Um. I'd start with Darwin's
Origin of Species. Seriously. Have you read it? I have. (Okay, I listened to the unabridged audiobook.) Obviously some parts of what he said have since been disproven or refined, but he was pretty rigorous in his attempt to offer evidence for everything he said, and to provide logical speculations for observed gaps in the evidence. If you have criticisms of Darwin's methods, I'd like to hear about them.
That statement is admittedly odd, so I'll say again in an attempt for clarity: I have read lots and lots explaining what evolution might look like, if it really does happen. But explaining how something might look if it is real is not at all the same thing as proving its reality. Drawing a detailed and well-organized diagram of what it might look like if an ancestor organism were to evolve into myriad species is not the same as proving that said organism really did any such thing.
Phylogenetic trees built from DNA and protein analysis do
nothing for you? Really? You find no compelling evidence for common ancestors in the observation that disparate species with highly differing characteristics have a great deal of genetic material in common? More than they strictly have to? Or in the striking similarity between "trees of life" built from molecular analysis and trees built from morphological observation?
If this evidence isn't compelling at all, Mr. Tweedy, then I have to wonder exactly what your specific definition of "proof" is, and whether your requirements for it are fully rational and necessary. In scientific terms, proving a theory usually means constructing a testable hypothesis and determining whether real-world observation is consistent with that hypothesis. It doesn't always mean experiment; sometimes empirical observation or induction are all that are practical. Evolution is supported by mountains of empirical observation, at the microscopic and macroscopic level, and there are many testable hypotheses that have been shown to be consistent with it.
It's rarely possible to prove any real-world theory with
finality. There is always the possibility of a better theory later that will replace the current one. Newton's laws of physics were considered "proven" by experiment after experiment for centuries; but we now know that they're approximations that only work under certain conditions. At very small or very large scales they fail to predict real observations, and so they have been supplanted by quantum physics and relativity. Both QP and relativity are considered "proven" in the sense of accurately predicting the results of testable hypotheses, but there are a lot of unknowns in each and they contradict each other in unusual ways. Yet scientists continue to believe in each.
Do you believe in relativity, Mr. Tweedy? Do you consider it "proven?"
What about gravity? To the current day, no one really understands how gravity works. Theories abound, but none have been conclusively proven over the other. Some have testable hypotheses; some do not; and in some cases the testability of the hypotheses is itself in sharp dispute.
In contrast to gravity, there is only one credible scientific theory that explains the multiplicity of species on Earth. Other theories that have been proposed (yes, I mean ID) are not scientific; they do not produce testable hypotheses.
Are you as skeptical about gravity as you are about evolution? If not, what would you consider the difference to be? What might elevate your faith in gravity above your faith in evolution? Both come down to empirical observation. Is there anything about the empirical observation of objects moving toward each other in the absence of other forces that might seem more "provable" to you than the empirical observation of disparate species with vast amounts of genetic material in common and morphological similarities that aren't survival advantages?
I am making an example of this particular argument because 1.) it was the evidence which Werethewild presented and 2.) I am not aware that any stronger arguments exist. Can you point me to an argument that is more definitive than this one, an argument which seeks to prove that evolution is true rather than simply taking as a given that it is?
My objection is that you mischaracterized the source material. You said that the author claimed to "prove" evolution and that the correlation observed "must have" a direct relationship. The author said no such thing. You did. If you're going to object to contrary evidence, please do so with accuracy.
There is overwhelming evidence that acorns become trees. I can see the budding acorns. I can see sprouting acorns on the ground. I can analyze the DNA of the acorn and the tree and see that it is the same genome. If I'm patient, I can observe while an acorn grows into a tree. Observation demonstrates that they are the same species. If I come upon the tree and the acorn with no preconceptions, then the evidence of my eyes will demonstrate that acorns become trees and trees drop acorns.
Sure. If you were patient enough and were willing to do all the work required to make those observations. If you had no reason to connect acorns and trees to begin with, would you consider it a valuable use of your time to watch that acorn for a few months and see what it does?
Evolutionary biology is the same. It does, granted, require a lot more patience and work to perform the observations. But they're there.
(Back in the Middle Ages, people believed that geese came from barnacles. The reason? Similar coloring, and the observation that no one ever saw those geese in summer. Therefore they must be underwater during that time. It was a while before someone put in the work to disprove that theory.)
My rational basis is simply that I trust my own reason and refuse to disregard it in favor of what an authority figure tells me. When I am presented with arguments which my reason cannot reject, I reevaluate my beliefs. But I do not change my beliefs simply because someone told me I should, even if that person is smarter than I am.
Have you ever,
yourself, Mr. Tweedy, watched an acorn to see if it grows into an oak tree? You just claimed above that it does. How do you know? Did you verify it with direct observation? Or are you believing what an authority figure -- a grade school textbook, perhaps, or a dictionary, or your parents -- told you about acorns? Is it simply that you were told this, and it doesn't contradict your sense of reason or anything you have observed?
If that's the case, what's different between acorns and evolution? In both cases, you're being told things by authority figures. Is there something about evolution that
does contradict your sense of reason? Is there some illogic in it that you perceive that experts don't? Does it contradict anything you have directly observed?
If it does, please explain. If it doesn't, why are you insistent on disbelieving evolution and not oak trees? What is it that bugs you?
Now let me turn that question around: Are you comfortable believing in something simply because smart people told you it was true?
Very often, yes, unless given a reason otherwise. I can't take the time to prove every single thing for myself. Now, if I hear something that goes against my own observations, or common sense, or sometimes my instincts, I might investigate further. Or if I just think it'd be fun to learn more. But I'm comfortable being told, say, that my car works on internal combustion without taking the engine apart to be sure. I'd void a lot of warranties if I was an equal skeptic on
everything.
You are well read (better read than I am) and know history. There have been countless times when the smartest people in a society–those revered and highly paid for their knowledge–were dead wrong about a particular issue. (Yes, women really are as intelligent as men. The continents do move. No, hail is not caused by witches.) Although the scientific community is most assuredly competent–brilliant–in a general sense, are you sure it is impossible that they could be collectively wrong about something?
Of course it's possible, and it happens all the time. And when they're wrong, eventually contrary evidence comes out and the scientific community -- over a period of many years, with some generational warfare and journal-based bloodshed -- changes its mind. That's called a paradigm shift. Kuhn wrote a book about it in 1962. It remains one of the most effective critiques of science on psychological grounds. (I.e., that science is performed by people, and despite their best conscious intentions most scientists can't put objectivity first.)
The thing is, though: there is
no credible competing evidence right now against evolution. There's no paradigm shift happening that says evolution is wrong. Not in the scientific community, anyway. No one has a better explanation. There are a lot of mechanisms hotly debated and being studied, and perhaps someday someone will discover something in those debates and studies that will turn all evolutionary theory upside-down. At the current moment, that would have somewhat more effect in biology than disproving relativity would have in physics.
But it isn't happening right now. Effectively all biologists believe in evolution, based on their own reason and their observation of the evidence.
I've listened to the authority figures, I've read some books (including
Origin of Species), I've examined the evidence to my own satisfaction, and I've come up with no reason to disbelieve evolution. I see much in the world that is strongly consistent with it, and nothing compellingly inconsistent. There's a lot of weird stuff in the world -- hell, I grow carnivorous plants, I could talk your ear off about weird stuff -- but nothing that makes me say "Evolution
could not possibly explain that." Rather, the weird stuff only increases my sense of wonder at the way beauty manifests in randomness and reproductive pressure.
So that's what
I see. My sense of reason says that evolution works, and that it's pretty damn cool. You clearly disagree, not just with me but with the scientific world. I still have to ask what you know that they don't know, that makes you disbelieve the scientific consensus -- it really is a consensus, not just a majority -- on grounds that you consider rational.
By the way, I really appreciate the civil and respectful attitude in your post. You're fun to talk to.
Thanks. I'm actually having some fun with this too. I know it's unlikely to go anywhere; but right now I'm not expecting to change your mind so much as I'm simply trying to keep the rhetorical knives sharp. The exercise itself is engaging, whether or not it achieves anything.
