Tuesday, February 19, 2008

On Evolution, Part 1 - It Is a Theory

I'm going to start another regular series of posts (like the series titled Biblical Wisdom), but this series will be devoted to clearing up the confusion and refuting the tired old criticisms... so in the future I can just say, see Part x.

First up, let's tackle the tired old "Evolution is only a theory" type of statement.

This is the "argument" that some creationists try to use to deflect the mountain of scientific evidence that backs up the theory of evolution. Oftentimes the offending person will add something like "It isn't truth, only a theory" or "Evolution is a theory not a fact." The reason that this lame "attack" sometimes works is that the vast majority of the public does not understand what a scientific theory actually is. Some of us "remember" learning back in school that a theory is not a certainty--it is more than a hypothesis but below a law.

Scientists do not use the terms that way. According to the National Academy of Sciences (NAS), a scientific theory is "a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses." There is no "magical" point at which a theory becomes a law. In point of fact, the term "law" is simply a descriptive generalization about nature.

Again, turning to the NAS, a fact is defined as "an observation that has been repeatedly confirmed and for all practical purposes is accepted as 'true.'" The fossil record and abundant other evidence testify that organisms have evolved through time. Although no one observed those transformations, the indirect evidence is clear, unambiguous and compelling. All sciences frequently rely on indirect evidence. Physicists cannot see subatomic particles directly, for instance, so they verify their existence by watching for telltale tracks that the particles leave in cloud chambers. The absence of direct observation does not make physicists' conclusions less certain.

When scientists talk about the theory of evolution (or the atomic theory, the theory of gravity, or the theory of relativity) they are not expressing reservations about its truth. Just the opposite.

Furthermore, it is necessary to define the word "evolution." From the archives of TalkOrigins.Org: Like so many other words, it (evolution) has more than one meaning. Its strict biological definition is "a change in allele frequencies over time." By that definition, evolution is an indisputable fact. Most people seem to associate the word "evolution" mainly with common descent, the theory that all life arose from one common ancestor. Many people believe that there is enough evidence to call this a fact, too. However, common descent is still not the theory of evolution, but just a fraction of it (and a part of several quite different theories as well). The theory of evolution not only says that life evolved, it also includes mechanisms, like mutations, natural selection, and genetic drift, which go a long way towards explaining how life evolved.

Calling the theory of evolution "only a theory" is, strictly speaking, true, but the idea it tries to convey is completely wrong. The argument rests on a confusion between what "theory" means in informal usage and in a scientific context. A theory, in the scientific sense, is "a coherent group of general propositions used as principles of explanation for a class of phenomena" [Random House American College Dictionary]. The term does not imply tentativeness or lack of certainty. Generally speaking, scientific theories differ from scientific laws only in that laws can be expressed more tersely. Being a theory implies self-consistency, agreement with observations, and usefulness. (Creationism fails to be a theory mainly because of the last point; it makes few or no specific claims about what we would expect to find, so it can't be used for anything. When it does make falsifiable predictions, they prove to be false.)

Lack of proof isn't a weakness, either. On the contrary, claiming infallibility for one's conclusions is a sign of hubris. Nothing in the real world has ever been rigorously proved, or ever will be. Proof, in the mathematical sense, is possible only if you have the luxury of defining the universe you're operating in. In the real world, we must deal with levels of certainty based on observed evidence. The more and better evidence we have for something, the more certainty we assign to it; when there is enough evidence, we label the something a fact, even though it still isn't 100% certain.

What evolution has is what any good scientific claim has--evidence, and lots of it. Evolution is supported by a wide range of observations throughout the fields of genetics, anatomy, ecology, animal behavior, paleontology, and others. If you wish to challenge the theory of evolution, you must address that evidence. You must show that the evidence is either wrong or irrelevant or that it fits another theory better. Of course, to do this, you must know both the theory and the evidence.

So the next time somebody says that evolution is just a theory you can smile and know that they are not well informed.

24 comments:

Al said...

CSM

You leave one important detail which is likely the most important piece of the puzzle. Are you arguing for evolution with or without a supreme designer? I don't believe anyone has actually argued that evolution is NOT a theory. You argument only inserted the phrase "just a theory" which is still a theory.

Most Americans probably support evolution but only as initiated by a supreme being.

csm said...

Al, I'm just describing and delineating the "just a theory" argument here. As the posting indicates, I will add more installments over time tackling and exposing the weaknesses in creationist "arguments."

Now, am I "arguing for" a supreme designer? No mention of that in this particular post, but what do you think, skippy? I'm an atheist.

The issue in this post is that people who throw out the old "just a theory" argument do so because they do not understand what at theory acutally is. Surely you must get that that was the point of this posting?

And I wish your last statement was true. At least then the old "god musta done it" argument could be saved for what caused the Big Bang. But there are many, many, many Americans who do not accept evolution because they do not understand it or because they desparately cling to outdated religious myths.

Al said...

Well Sherlock, I do realize you are an atheist with a very obvious Christian upbringing. That stated, scientist with religious roots often present theories without the bias of their religion. I thought in stating the theory here, maybe, just maybe you might see past your atheism to understand many Americans would buy into this theory as long as a supreme designer was behind it. Many huge problems with DNA and such are much more palatable with that scenario.
Evolution just naturally ties in to origins.
Evolution has a flavor of atheism to it and many Americans are turned off by that fact. For a vast number of Americans, that is a large factor.

Ceroill said...

Well, see, that's part of the big misunderstanding. Evolution doesn't deal with how it all began, just with how it changed over time. I suspect the vast majority of religious scientists who hold to the deific origins of life see it as just that. The initial origin. Not that there has been constant steering and manipulation. Not that humans were specially created. Just that the initial mysterious impetus for life itself might be divine.

derF said...

Today's Palm Beach Post announced;

Evolution makes the grade in state

But a late amendment to the science curriculum calls it 'a scientific theory.'

Tallahasse -- Evolutions got an opposable thumbs-up when the Florida Board of Education agreed to include it for the first time in the state's public school curriculum.

But the board didn't make as big a change as the creators of the new curriculum wanted.

While all seven Board of Education members agreed that evolution should be studied in public schools,they slit, 4-3, in favor of an 11th hour amendment that stipulated evolution be taught as a 'scientific theory.' The amendment came after opposition to the standards primarily from conservative Christian groups.

csm said...

Y'see, Al, god has nothing to do with things scientific. Gods invoke miracles and miracles cannot be explained scientifically.

And YES, exactly, Bob!

Thanks for the news from Palm Beach, derF! But what in the name of Darwin and dinosaurs did they think they were going to teach before amending the proposal to teach evolution as a 'scientific theory?' What else were they going to teach it as?

Basically, that story makes my point. People do NOT know what a 'scientific theory' actually is.

Ceroill said...

Here's another fun news item: Gene Studies Confirm Out of Africa Theory

derF said...

Yes, of course I'm always a little reticent about citing anything 'Palm Beach.' Its like saying, "Extra! Extra! Breaking news from the seat of entitlement!" However, I thought it did illustrate your point. It also revealed the workings of the GREAT MINDS in Tallahassee. Don't you find it mind-boggling that in 2008 the Florida Board of Education will be including Evolutionary Theory within its curriculum for the FIRST time?

In fairness to The Post, I should mention that the article was followed by definitions for the terms Scientific Theory and Scientific Law. In this case, however, I suspect the term theory is being used to blunt the science that the theory contains.

Al said...

"god has nothing to do with things scientific. Gods invoke miracles and miracles cannot be explained scientifically."

Oh well, this is typical, actually no csm. This is why your grasp of these god(s) vs. belief in a supreme designer is suspect. The fact he kicked it all off and started the process in no way derails the study of the theory. All it does is make the theory more realistic in the mathematical realm. Probability is also a science and the Probability theory says uh-uh without intelligent direction.

Before you throw this one out there, Time does not solve the probability problems. Time is the equivalent of “God did it”.

Speaking of miracles, I would call Big Bang a miracle. It violated numerous scientific laws. So ya see CSM, there is the need for a designer after all.

csm said...

No, Al, there is NOT a need for a designer. Call this designer god or whatever, I don't care, he/she/it is NOT needed. God as the big designer is nothing but a crutch for the weak-minded.

And do tell, please, what scientific "laws" were violated by the Big Bang and how they were violated?

Furthermore, you (or anyone else) can believe in a god or designer or whatever all they want. It makes no difference to me until you (or anyone else) tries to force that belief on other people by teaching it in schools. It does sadden me that people believe in ghosts and gods and fairies and goblins, but I have resigned myself to the fact that such beliefs will not end in my lifetime (if ever). So your point, if you have one, that belief in an ethereal entity starting things off does not "derail the theory" is correct, as long as that belief does not become part of the theory (because then it is not a scientific theory).

csm said...

Also, I forgot to comment on the stupidity of your "Time is the equivalent of “God did it”" statement. No it is not. There are numerous scientific tests and studies that show us the age of the Earth and the duration of time that passed. Couple that with genetic mutation coupled with natural selection over millenia and it paints a nice picture. Compare that to a god with no evidence and the two are completely different.

csm said...

Hey, derF, can you copy and paste the definitions for scientific theory and scientific law? I'm curious, but I'm sure you are correct that the creationists are using the word theory as a ploy to diminish the astounding significance and relevance of evolution.

derF said...

Sorry, I can't copy & paste but I can type them out. Please bear in mind that any and all typos are purely my own words.

"Scientific theory vs. scientific law

A scientific law is an observation of the physical world, whereas a scientific theory explains it.

Scientific theory: it 'is a widely supported and widely accepted explanation of nature and is not simply a claim posed by an individual,' according to the new science standards for sixth grade.

Scientific law: A 'description of a specific relationship under given conditions in the natural world,' the sixth-grade standards say.

Al said...

"No, Al, there is NOT a need for a designer"

Sorry, wrong again. Try as you may, ignore the obvious all you like. Americans are not stupid enough to believe the universe created itself, or has always been. The world just doesn’t work that way. The ol’ “weak minded” argument? Typical, so you only read and trust strong minded atheist scientist csm? Typical as well.

I could care less if it is “in the theory” or taught in the schools. Some things are just readily apparent and only the paranoid xenophobes would attempt to tell the rest of the world that obvious intricate design comes about through time and mutations minus a designer.

No CSM, I’ll follow the lead of a whole host of reputable scientist on to field of common sense. I think you should enter this contest since you have it all figured out. It would really help out some of our top scientist.

The Origin of Life Project

csm said...

But I guess Americans ARE stupid enough (your words) to believe that god always has been, huh?

And again, your weak-mindedness shines thru as you keep going back to what started it all (origins) claiming that I have stated that I know how it happened?!?!?! Step back, take a deep breath, and re-read my postings and comments. Never once did I say I know how the cosmos started. I mention the Big Bang as a very reputable theory but do not state what, if anything, was the cause of said bang. So here's a hearty fuck you farley!

By the way, the phrase you were looking to use is that you couldn't care less. However, given the content of your comments, I think you got it right the first time. And those of us who care about educating the next generation to compete in the world do care about such distinctions as, oh, let's say, teaching science in science classes.

Al said...

CSM, you are such a harebrained little fella. No, I got it right. I could care less. But, you just don't get it so I give up trying.

At least you finally admit to know you have no clue how it happened. The reason I keep going back to origins is because I support evolution so what's to bring it up?

But, no need for a designer huh? OK csm, if you say so.

Let's just say you are completely clueless and leave it with that. Good luck with the basketball team.

csm said...

If anyone had a fuckin' clue what Al is talking about here please enlighten me.

csm said...

Let me try one more time, Al. Please answer this and stop the useless clucking. If you must have a designer because the world is too complex to have started without one, then you must have a designer for the designer, and so on, ad infinitum. Or do you "believe" something else?

coreydbarbarian said...

man, you 2 are funny.

csm, we live in an age where the masses do not trust in the viability of science, an age of religious revivalism, conservative politics and even fundamentalism.

argue with a conservative, or worse, a fundie, and you will soon see appeals to a "common" sense of things, as in "everybody knows this" or "americans know that".

simply put, people cannot trust in things they cannot understand, no matter who vouches for it.

witness einstein - we all agree that e=mc^2 seems to hold up to scrutiny, even al. but ask folks on the street if they accept a theory that time (and space) are not fixed values, but relative...
they'll likely tell you that they're not sure about that part, sometimes science is wrong and common sense seems to tell a different tale.

not trying 2 defend, but sharing observations, and feeble attempts at understanding the mindsets of two-dimensional beings...

oh yeah, and i always thought the saying was, "chuck u. farley". ;)
---
al,
stop provoking the atheists.
for one thing, they will not hesitate to fling poo on you when agitated.
2ndly, it's not nice.

play nice, al, play nice. ;)

csm said...

As always, you make many reasonable comments and suggestions, Coreyd... however, I would add that no one is trying to stop the theory of relativity from being taught in schools (or attacking its credibility with "just a theory" tags) even if they do not understand it or would not say they agree with it if asked "on the street."

derF said...
This comment has been removed by the author.
derF said...

Yeah, Al, though I may sometimes have trouble internalizing unfamiliar concepts, I am not a paranoid xenophobe. Even so, I can not accept the world around me as an intricate design. Although the concept is not unfamiliar to me, it seem impossible to swallow without a liberal dose of assumption.

BAWDYSCOT said...

One thing not mentioned so far is what the hell do we do with the growing number of people who believe the Bible is the be all and end all concerning how we got here. I personally don't think anyone will ever find out how this shitball got started(who knows maybe the intelligent designer rolled over and died after the seventh day!), but we have people, including our dipshit of a President, who believe everything in the good book and nothing outside of it. These are the people I worry about.

csm said...

Well said, Bawdy. What would you do about that situation? I think we need to continue to fight to keep the education system free of that crap (religion). It would be impossible to change the majority of those who are today inflicted with the god-virus, but by keeping it out of the public school system (I know, I know, Bawdy, states' rights) we will be providing for the common good by edu-ma-cating them on science and other areas of true knowledge.