Physics Nobelist takes stand on evolution

"By the same standards that are used in the courts, I think it is your responsibility to judge that it is the theory of evolution through natural selection that has won general scientific acceptance. And therefore, it should be presented to students as the consensus view of science, without any alternatives being presented."

--Dr. Steven Weinberg

The following is a transcript of testimony to the Texas State Board of Education. Dr. Steven Weinberg, professor of physics at the University of Texas at Austin and a Nobel prize winner for electroweak theory, addresses the Board.

DR. WEINBERG: Thank you. Hello. Thank you for the opportunity to talk to you. I should say at the outset that I haven't read the textbooks in question and I'm not a biologist.

My Nobel Prize is not in biology, but is in physics. But I have been a physicist for a long time. And I think I have a good sense of how science works. It doesn't deal with certainties. We don't register things as facts that we have to swear allegiance to.

But as mathematics and experiment progress, certain bodies of understanding become as sure as anything reasonably can be. They attract an overwhelming consensus of acceptance within the scientific community. They are what we teach our students.

And the most important thing of all, since our time is so precious to us, they are what we assume as true when we do our own work. Evolution -- the theory of evolution through natural selection has certainly reached that status as a consensus.

I've been through these issues not very much professionally in recent years, but I was on a panel of the National Academy of Sciences some years ago that reviewed these issues in order to prepare an amicus brief in a similar argument that was taking place in Arkansas at that time. At that time, it had reached the courts. We know that there is such a thing as inheritable variations in animals and plants. And we know that these change through mutations. And it's mathematically certain that as given inheritable variations, that you will have evolution toward greater adaptation. So that evolution through natural selection occurs can't be in doubt.

As I understand it, many who want to put alternative theories into our textbooks argue that, although that may be true, we don't know that that's all that happens, that there is not some intelligent design that also assists the process of evolution. But that's the wrong question. We can never know that there isn't something beyond our theories. And that's not just true with regard to evolution. That's true with regard to everything.
We don't know that the theory of physics, as it's currently understood, correctly accounts for everything in the solar system. How could we? It's too complicated. We don't understand the motion of every asteroid in the asteroid belts. Some of them really are doing very complicated things. Do we know that no angel tips the scales toward one asteroid moving a little but further than it otherwise would have in a certain time? No, we can never know.

What we have to do is keep comparing what we observe with our theories and keep verifying that the theories work, trying to explain more and more. That's what's happened with evolution and it continues to be successful. There is not one thing that is known to be inexplicable through evolution by natural selection, which is not the same as saying that everything has been explained, because it never will be. The same applies to the weather or the solar system or what have you.

But I can say this, and many of the peak scientists here will have said, I am sure, the same thing. You must be bored hearing this again and again. But how can you judge? I'm not a biologist, you're not biologists.
There is a natural answer which is very congenial to the American spirit, I think. And that is, well, let the students judge. Why shouldn't they have the chance to judge these issues by themselves? And that, I think, is the argument that many are making.

But judge what? Judge the correctness of evolution through natural selection? Judge the correctness of Newton's law or the conservation of energy or the fact that the Earth is round rather than flat? Where do we draw the line between the issues that we leave open to the student's judgment and the issues that we teach as reasonably accepted scientific facts, consensus theories?

The courts face a similar question. They often are presented with testimony or testimony is offered, for example, that someone knows that a certain crime wasn't committed because he has psychic powers or someone sues someone in tort because he's been injured by witchcraft. The Court does not allow -- according to current doctrines, the Court does not allow those arguments to go to the jury because the Court would not be doing its job. The Court must decide that those things are not science. And the way the Court does is by asking: What -- do these ideas have general scientific acceptance? Does witchcraft have general scientific acceptance? Well, clearly, it doesn't. And those -- that testimony will not be allowed to go to the jury.
How then can we allow ideas which don't have general scientific acceptance to go to high school students, not an adult jury? If we do, we are not -- or you are not doing your job of deciding what is there that is controversial. And that might be an interesting subject to be discussed, as for example the rate of evolution, the question of whether it's smooth, punctuated by jumps or whether it's -- or whether it's just gradual. These are interesting questions which are still controversial which could go to students and give them a chance to exercise their judgment.

But you're not doing your job if you let a question like the validity of evolution through natural selection go to the students, anymore than a judge is doing his job or her job if he or she allows the question of witchcraft to go to the jury. And why this particular issue of evolution? Why not the round Earth or Newton's theory or Copernicus, the Earth goes around the sun? Well, I think it's rather disingenuous to say that this is simply because there's a real scientific conflict here, because there is no more of a scientific conflict than with those issues.

I do get involved in this issue. I think it's clear that the reason why the issue was raised with regard to evolution is because of an attempt to preserve religious beliefs against the possible impact of the theory of evolution.

I don't think teachers have any business either preserving religious beliefs or attacking religious beliefs. I think they should teach science.

And science, as the courts understand it, in that other context, is what is generally accepted by scientists. And what is the evidence that evolution through natural selection is generally accepted through science? I don't think -- general acceptance doesn't mean unanimity.

I know there are Ph.D. scientists who take an opposite view.

There's not one member of the National Academy of Sciences who does.

There's not one winner of the National Medal of Science who does.

There's not one Nobel Laureate in biology who takes the view that there's any question about the validity of the theory of evolution through natural selection or that there is any alternative theory that's worth discussing.
So by the same standards that are used in the courts, I think it is your responsibility to judge that it is the theory of evolution through natural selection that has won general scientific acceptance. And therefore, it should be presented to students as the consensus view of science, without any alternatives being presented.

Thank you very much.