I sure wish more people understood the meaning of theory in science, but at least Piers Sellers does a good job of explaining the concept. I try to hammer into my students (as my teachers hammered into me) the primacy of evidence — observation and measurement — but evidence always has to be for or against something, and that something is theory. You can’t have a theory without evidence, and you can’t have evidence without a theory to give it meaning. So I’m always happy to see another explanation of this core concept of science.

Fundamentally, a theory in science is not just a whim or an opinion; it is a logical construct of how we think something works, generally agreed upon by scientists and always in agreement with the available observations. A good example is Isaac Newton’s theory of gravitation, which says that every physical object in the universe exerts a gravity force field around itself, with the strength of that field depending on its mass. The theory—one simple equation—does a superb job of explaining our observations of how planets orbit around the sun, and was more than good enough to make the calculations we needed to send spacecraft to the moon and elsewhere. Einstein improved on Newton’s theory when it comes to large-scale astronomical phenomena, but, for everyday engineering use, Newton’s physics works perfectly well, even though it is more than three hundred years old.

One danger of the public misunderstanding of this idea is that they do equate theory and opinion; they tear down successful theories with rhetoric and ignorance, and they also elevate nonsense by labeling it, without comprehension, a theory. And I could piss in the snow and call it a book, too.

But theories are abstract, after all, so it’s easy for people to get tricked into thinking that because something is based on theory, it could very likely be wrong or is debatable in the same way that a social issue is debatable. This is incorrect. Almost all the accepted theories that we use in the physical and biological sciences are not open to different interpretations depending on someone’s opinion, internal beliefs, gut feelings, or lobbying. In the science world, two and two make four. To change or modify a theory, as Einstein’s theories modified Newton’s, takes tremendous effort and a huge weight of experimental evidence.

This is something that should be explained to everyone visiting Answers in Genesis and their horrible dishonest “museum” and “ark park”. The central argument Ken Ham always makes is a demolition of the whole concept of theory — he claims that any alternative explanation, no matter how much it ignores the evidence, is a theory, and all theories are equal, and therefore, his bizarre, highly subjective and ideologically driven interpretation of the words of his holy book are just as much deserving of the title of “theory” as the hard-earned, constantly tested, well-supported by evidence theory of evolution.

And that’s dangerous. Ken Ham uses the degradation of theory to peddle nonsense to the rubes and make money and promote his narrow religion, but as the article explains, it’s also being used to corrupt decision-making about climate that endangers every human being on the planet.