Theory, or hunch?
I’ve enjoyed reading the recent evolution versus creationism discourse in the Daily. It reminds me of the expression, “Anyone can have a theory; wake me up when you find the truth.” The tendency for some people to dismiss evolution as “just a theory” is indicative of just how poorly they understand what a scientific theory is. In their book, “A View from the Center of the Universe,” Joel Primack and Nancy Abrams do a wonderful job of explaining this very issue.Most of us are imprecise in our usage of the English language, which is fine when writing a grocery list. We use the words “pop” or “soda” instead of writing, “six 12-oz cans of Pepsi Cola.” But true understanding of a subject requires that it first be defined. Only then we can be clear in our own minds as to what we are, and are not, talking about.Take the word “theory,” for example. “Theory” is frequently used when all one really has is a belief, an idea or a hunch – or perhaps even a put-down (“Yeah, in theory”). Nevertheless, using the word “theory” in lieu of “a possible explanation” is OK in everyday usage because the individual isn’t betting his or her life on it.However, scientific theories literally “bet their life.” For a theory to be truly scientific, it must make predictions that are testable. Scientists continually test theories to see if they can disprove them. A scientific theory is a working hypothesis, a proposed picture of reality to help us think about reality, which is why scientists test theories continually. Testing theories also helps scientists gain a better understanding of them. Theories get tested until they fail. Physicists have been testing the theory of relativity for almost a century. Although it’s never failed, it’s still tested. That’s what gives the scientific community confidence in the theory’s soundness.We must remember that a scientific theory can be disproved by a single counter-example, but it can NEVER be proved true because that would mean it couldn’t be refuted. If a theory can’t be refuted, by definition it’s not a scientific theory – it’s faith. Physicists know full well that Einstein’s general relativity can’t be completely right because it’s inconsistent with quantum mechanics, the theory upon which the entire electronics industry is based. (By the way, every time we fly in an airplane, pop a muffin in the toaster or send an email, we’re doing so predicated upon a theory.)So isn’t this contradictory? Not at all, because a new scientific theory doesn’t necessarily rule out a preceding theory. Once a field of study undergoes a revolution that creates a solid intellectual foundation, such as Newtonian mechanics gave physics, that foundational theory can stand forever.Newtonian physics is as accurate as ever even though it’s been eclipsed by Einstein’s theory of relativity. Why? Because relativity defined the limits within which Newtonian mechanics are reliably accurate. Einstein’s theory of relativity doesn’t replace Newtonian physics. It encompasses it. Simply stated, Einstein’s relativity theory expanded the scope of observation and prediction to explain things beyond the ken of Newtonian physics.As an illustration, take a sheet of paper and draw a 1-inch square and label it “Newtonian physics.” Then on the same sheet of paper, draw a 4-inch square around the 1-inch square, and label the larger square “relativity.” Metaphorically, both theories will make the same predictions within the 1-inch-square box (even though the results are explained differently). However, the area outside the Newtonian 1-inch box but inside the 4-inch relativity box represents the conditions under which the theory of relativity, and not Newtonian physics will make accurate predictions. (If you REALLY want to impress your friends, overlay a 3-inch by 6-inch rectangle labeled “quantum theory” onto the “Newtonian'”and “relativity” boxes, arranging it so the “Newtonian” box is contained within the “quantum theory” rectangle. Next, draw a 10-inch-diameter circle around the entire graphic and label the circle “super string theory? Now take a step back and pat yourself on the back because you’ve just metaphorically illustrated a scientifically-supported graphic of mankind’s understanding of the physical universe.)Another seemingly contradictory factor within the evolution-vs.-creationism debate is that some people view theories within the context of how scientific discoveries are reported in the media. We continually read about what foods a new study indicates are healthy, what medical treatments are currently being touted, or how unsafe our water is. Then a year later, another study often seems to find the opposite.However, even though tofu may have been bad for you last year and good for you today, the fundamental theory of biology (evolution) did not change. These types of minor discoveries come nowhere near challenging it.The reality is that biology after Darwin underwent a transformation from a loose collection of observations and speculative ideas to a discipline with immense amounts of reliable data organized by an overarching theory that may last forever.Unlike truth in religion, a scientific truth is always open to question, and scientists actively seek out the most fertile questions-that’s their job. So the next time someone uses the word “theory,” ask them if it’s predicated upon hundreds of thousands of observations, years of painstaking analysis, and then tested and retested under the most stringent of laboratory conditions – or if it’s just a hunch. Butch Mazzuca, a local Realtor and ski instructor, writes a weekly column for the Daily. He can be reached by e-mail at firstname.lastname@example.org