Pages

Friday, May 30, 2008

Theory vs Hypothesis

In everyday language, I person might say they have a theory about something and mean they have a possible explanation for an event which has yet to be proven or disproven, essentially using the word interchangeably with the word hypothesis. In the scientific community, however, the word has a much stronger meaning. The Theory of Gravity, for instance, doesn't say that maybe if I drop an apple it will fall to the ground, it says if I drop an apple, then it will definitely fall to the ground. The Theory of Relativity is the same way, and if I had any idea of exactly what the Theory of Relativity is all about I would explain it here, but suffice to say that in science the word Theory is much more akin to the word Law than the word Hypothesis. In fact, here's what the National Academy of Sciences has to say about theories:
"Some scientific explanations are so well established that no new evidence is likely to alter them. The explanation becomes a scientific theory. In everyday language a theory means a hunch or speculation. Not so in science. In science, the word theory refers to a comprehensive explanation of an important feature of nature that is supported by many facts gathered over time. Theories also allow scientists to make predictions about as yet unobserved phenomena."

All of which brings us to the Darwin Fish at the top of this post. When scienctists or teachers talk about the Theory of Evolution, they are describing to their proteges and pupils a set of well-established scientific facts, the main points of which are not disputed. But to the average non-scientist the name itself implies that this is just a hunch - the best we can come up with for the time being, maybe, but likely to be obsolete once we get all the facts in. Not suprisingly, this leaves the door wide open for anyone who would rather not believe in evolution.
Is the solution to change the name to the Law of Evolution? Probably not. A law and a theory, after all, have two distinct meanings, just as theory and hypothesis do. But the teaching of evolution probably needs to do a better job emphasizing that there really is no debate over evolution. The big picture is clear, and even though there are small details that have yet to be uncovered they are not going to change the overall appearance of that picture in any major way. Can the general public get this? There's hope. Recently, the public seems to have gone (okay, begun to go) through this shift with regard to global climate change. Just a couple years ago, few people realized that the debate over whether or not human activity was affecting global climate was essentially over. Now even the skeptics are left with nothing to do but quibble over minor details and predictions about local impacts, but that seems like a topic for another post.

No comments: