Law versus theory

PZ has a couple of posts going right now where he takes down some common creationist canards. One post absolutely wrecks Ann Coulter (who, incidentally, has some real kiddie rhetoric going on – it’s just awful), and the other takes on Bryan Fischer. Each post is excellent, but PZ skims over something I would like to address in the latter link. Here are some excerpts from Fischer’s writing:

First Law of Thermodynamics. This law (note: not a theory but a scientific law) teaches us that matter and energy can neither be created nor destroyed…

Second Law of Thermodynamics. This law (note: not a theory but a law) teaches us that in every chemical or heat reaction, there is a loss of energy that never again is available for another heat reaction…

There are two kinds of people who have confusion over what a scientific law is versus what a scientific theory is. The first kind includes much of the general public. These people will have a basic misunderstanding, but they don’t tend to go about basing arguments upon it. The second kind, however, is an ugly little bunch. They include the likes of Fischer who also share the general lay public’s misunderstanding, but they then go about premising a bunch of bullshit on it.

A scientific theory and a scientific law are effectively the same thing. The latter term tends to be used more in physics than anywhere else, but that is a matter of history and convention more than anything. There is no magic property that makes the theory of gravity any different from the law of gravity. Both terms describe the same thing. We’re merely talking about banners and titles here, nothing of scientific value. Any person interested in science ought to learn this pretty quickly.

I recall sitting in an introductory biology course many a year ago when one student asked the professor the difference between a theory and a law. It is rare (though not absent) for “law” to be used in biology, so I’m not sure what spurred the question, but the professor answered it exactly right: There is no significant difference. I had a good deal of respect for the student at that moment. He was ignorant of something, so he got an answer. Creationists like Fischer, however, don’t do that. They understand the way we conventionally use terms and assume they can aptly apply that understanding to science. They cannot. They are wrong and scientifically irresponsible to do so.

But who’s willing to bet Fischer keeps pretending there is a difference even after being told there isn’t one? I am.

Because it’s worth repeating

A creationist in one of the comment sections recently repeated this old canard.

the dictionary says (among other things) that a theory is:
1. contemplation or speculation.
2. guess or conjecture.

there i go? again?
you just seem pretty intent on disparaging arguments but not refuting them.

This is yet another point where atheists and other non-deluded people are willing to be honest, all the while watching creationists do just the opposite. It’s like it’s just so damn inconvenient to come to a straight-forward, truthful understanding of basic concepts for the religious that lying has become okay for them; the ends justify the means.

So it is worthwhile to repeat, for the nth time, just what a theory is and is not.

Insofar as my theory that ice cream is great can be considered a theory, yes, creationism is a theory. But it is not in any way a scientific theory. The requirements to reach this high level are rigorous. For starters, what predictions does creationism make? What experiments can be carried out to falsify the hypothesis? Can others repeat these experiments? Are there other plausible explanations? Are there better explanations?

The word “theory”, as any educated, honest person knows, carries far more weight in science than it does for the lay public. In truth, the word gets mixed up in casual talk within science, even sometimes becoming conflated with “hypothesis”, but no one really blinks because the context allows for the use of shorthand. Think to Richard Dawkins’ style of writing. He uses personification all the time, especially when discussing natural selection. He will start out with qualifiers and scare quotes – “Natural selection ‘wants’ to weed out the bad genes” – but as he goes on, the reader comes to an understanding of the fact that the good doctor is bringing evolutionary biology to life via a particular way of writing. It becomes obvious that it is inappropriate to apply anthropomorphic qualities to what Dawkins is describing – and it is context that allows for this.

But in public forums or political circles, there can be no assumed knowledge of science and what its terms mean; it is a danger to allow for the use of loose language without qualification. That is why it is so important to distinguish between the lay definition of “theory” versus its scientific definition. In science it references something which has evidence, has been tested, has journal papers all about it, and usually there is a high degree of consensus. The Big Bang, evolution, global warming, plate tectonics – these are all theories. Creationists have no theories. They have no evidence, no reason, no logic, no testing, no raw data, no way to interpret any sort of observation in a way that holds any scientific significance.

What is a Theory and What is Not a Theory

Ever since the media (apparently not McCain) decided it would be a good idea to finally vet Sarah Palin, much has come to light. I’ll leave discussion of tax plans and foreign policy to the political boards, but there is one thing which really needs to be noted. Palin has said in the past that she thinks both evolution and creationism should be taught, referring to them as theories. She later backed off that statement. In the past couple of months, she further clarified her position:

Couric: Should creationism be allowed to be taught anywhere in public schools?

Palin: Don’t have a problem at all with kids debating all sides of theories, all sides of ideas that they ever – kids do it today whether … it’s on paper, in a curriculum or not. Curriculums also are best left to the local school districts. Instead of Big Brother, federal government telling a district what they can and can’t teach, I would like to see more control taken over by our school boards, by our local schools, and then state government at the most. But federal government, you know, kind of get out of some of this curriculum and let the locals decide what is best for their students.

To any person remotely familiar with science, there should be a glaring initial error in that statement. It doesn’t have to do with the merits of debating evolution, but with this notion that there are alternative theories to evolution. Given the context of what Palin has said in the past in addition to her beliefs, it’s overwhelmingly clear she has it in her head that creationism is somehow a theory. Insofar as my theory that ice cream is great can be considered a theory, yes, creationism is a theory. But it is not in any way a scientific theory. The requirements to reach this high level are rigorous. For starters, what predictions does creationism make? What experiments can be carried out to falsify the hypothesis? Can others repeat these experiments? Are there other plausible explanations? Are there better explanations?

In the case of evolution, we see predictions a-plenty being made. We could easily falsify the hypothesis by finding a rabbit in the pre-Cambrian. And we can culture any number of species and see how they adapt to their environments. In truth, the evidence is far more overwhelming, far more testable, far more falsifiable, and far more concrete than I’ve just touched on here. But that’s a question for later. The question here is, why doesn’t the daughter of a science teacher know the difference between a layman theory and a scientific theory? Hell, why doesn’t an educated adult know this?

The truth is evolution is the backbone to every field of biology. It is what creates a coherent picture. From nucleic acids to substrates fitting active sites to differential survival of members of a population, evolution provides the only sensical view of life from its beginnings – and it has yet to be falsified to any point that isn’t merely a shaping and strengthening of the theory. Sarah Palin should know better.