According to the New York Times, “in a poll released yesterday 42% of Americans believe that all life has existed unchanged since the beginning of time, while 60% believe that either a creationist or intelligent design doctrine is the way to go”:http://www.nytimes.com/2005/08/31/national/31religion.html?ex=1283140800&en=39489e715718912f&ei=5089&partner=rssyahoo&emc=rss.
Dr. Eugenie Scott, and outspoken supporter of teaching only science in the science classroom, got right to the cultural heart of this issue: “… the findings were not surprising because ‘Americans react very positively to the fairness or equal time kind of argument. In fact, it’s the strongest thing that creationists have got going for them because their science is dismal,’ Ms. Scott said. ‘But they do have American culture on their side.'”
American’s have always supported the idea of hearing both sides of an issue. The disconnect is that this is not how science works. Science works by weighing all ideas equally until they are tested against data. That data might already exist, but if it doesn’t you have to go and collect it. Data, facts, discern between ideas. Some ideas explain the data well, and are then elevated to the level of a scientific theory. What survives this process is then applied by science to continue to try to understand nature. What student’s in the classroom must learn to become good scientists are two things: what is the process by which you discern good from bad ideas, what what are the scientific theories that survived that process and continue to teach us about the universe?
The end result of science is not opinion. In a political debate, two opposing ideas carry equal weight. Often, both prove to work out in one fashion or another. But that is not how nature works. Nature works by a single, rational mechanism whose true function we have yet to totally illuminate. We understand a great deal, but we also know and are humbled by the fact that there is much unknown even to the most successful theory. Here are a few examples:
* The Theory of Gravity: explains the macroscopic motion of the universe in perfect detail. Predicts that objects of a certain mass, or heavier, will collapse under their own gravitational attraction into a black hole. Fails to predict the physics inside a black hole, where quantum mechanics has an equal role due to the small size of the object.
* The Standard Model (Quantum Mechanics + Special Relativity): explains the interactions between all known fundamental particles as symmetries under mathematical gauge groups. Overwhelmingly successful at understanding the behavior of the quantum world at high energies. Fails to include gravity at all. Depends on 21 free parameters whose values are unpredicted and must be measured.
* Theory of Plate Tectonics: Explains all known geological surface motion on the Earth. Fails to make predictions about the timing of earthquakes.
Other theories competed with these. They were fine ideas, mostly because there wasn’t yet the data to choose between them. For instance, the many particles discovered between the 1920s and 1960s, all of which seemed to be “fundamental”, could be explained by two hypotheses: the “quark” model, and the “bootstrap” model. In the quark model, unseen, tightly bound “quarks”, when paired or tripled up, could explain the many kinds of particles (and you only needed 3 quarks!). The bootstrap model said that the lightest particles experienced self-interactions and pulled their masses up “by their own bootstraps”, thus giving rise to an apparent zoo of new particles. Data from experiments in the 1960s revealed the quark hypothesis made correct predictions, while the bootstrap model failed. So until data comes along, all ideas are really just philosophies.
String theory is an excellent example. String theory is a very simple, elegant mathematical framework that might be the fundamental description of the universe. It’s based on very sound mathematics and any graduate student with the proper training for other branches of physics can sit down and learn string theory’s details. However, not a single prediction made by string theory has ever been tested, nor can many of them be tested right now. That makes string theory a very elegant philosophy. Just because the math is nice, doesn’t mean nature has to abide by it.
However, what differentiates string theory from, say, positing that the 21 free parameters of the Standard Model are set by an “intelligent designer”, is that string theory actually makes predictions about new phenomena that can be observed. One concrete example: string theory requires at least 10 space dimensions, which is 6 more than we know about. It predicts that gravity, unlike the other forces we know about, can travel into the extra dimensions. We can therefore test for extra dimensions by (1) testing the strength of gravity at very short distances (less than a millimeter) and (2) looking for graviton production at high energy particle colliders, which manifests as a lot of undetectable “missing” energy. That’s the hallmark of a good scientific hypothesis: predictions that can be tested.
I hope that some of the 60% of America that needs an intelligent designer, or who think we’ve been around in our present form since creation, read this. I hope that for a moment, just a moment, they feel the humility and the doubt that this universe ought to instill in such a fragile creature as a human. We are a small part of a long history. We are lucky to have evolved enough to not only study this universe, but also to keep a record of our knowledge and pass it on to the next generation. No hypothesis that cannot ever be tested, that does not make predictions, is sound science. It is a discredit and a disservice not just to our future scientists, but also to all those in the U.S. that benefit from scientific innovation, to force creationism/ID into the science classroom to be taught as if they have the same stature and power as the Theory of Evolution. Creationism has never made an accurate prediction about the universe born out by the data, except maybe “let there be light”. Intelligent design, which is no better, has in its 15 years of existence never made a single prediction that can be tested. Evolution, which at first seemed implausible given the religious teachings of the times, became overwhelmingly undeniable as the data accumulated and its predictions were born out. How can you argue that teaching unsuccessful ideas about the universe has any place in science next to a successful theory of life’s development?