the Scott Stein


There are lots of Scott Steins out there, but this is the Scott Stein, the one you’re looking for

Only a Theory
Posted on Thursday June 22, 2006 at 4:03pm.
I’ve seen the following on bumper stickers: “Evolution is a theory” or “Evolution is only a theory.” The point, of course, with theory in italics, is to make Evolution seem like it’s just some guy’s idea. We all have theories, after all, about all sorts of things. Some people have a theory that God planted the dinosaur skeletons deep in the ground to test our faith. Theory here is being used in a disparaging, nonscientific way to mean any old idea we happen to entertain, as distinct from fact, which is understood as supported by evidence and true. This can be seen in a variation of the bumper sticker that goes something like: “Evolution is a theory, not a fact.”

In scientific circles, theory has no such disparaging connotation. So, though scientists agree that Evolution is a theory, not a fact, it is not because they doubt that some version of Evolution occurred and is occurring. It’s because of the meaning of theory and fact in a scientific context. As an example, water boiling at 212 degrees Fahrenheit under controlled conditions is a verifiable fact. Explaining why it does so, and taking into account a large body of other related facts, requires a theory. Some theories are stronger than others, but in science, calling something a theory does not imply that it is wrong or false or just some guy’s opinion. The bumper sticker implies otherwise, and its effectiveness depends on a general misunderstanding of how scientists use words.

Anyway, here’s a bumper sticker I’d like to see: “Gravity is only a theory.”

Because it is. But that doesn’t mean we jump off the roof.