I read a post over on the NCSE's blog, that is the National Center for Science Education. Normally I really enjoy reading their blog and frequently refer to their site to keep abreast of science education in this country. Often I learn a few new things as well. However, this particular entry, Misconception Monday: Hypotheses, Theories, and Laws, Oh My!, left me rather perplexed. In a nutshell the author, Stephanie Keep, defined Hypothesis, Theory and Law. I was looking forward to it, especially since I've posted on this topic before (Arguments XIX -- Hypothesis, Theory, and Law), but the article rather blurred the lines between them to the point they were barely recognizable, well at least to me. Now granted my science education from HS and college was a while ago, but what I learned put a much sharper demarcation between them than was described here.
I understand there is no absolute universal definition of the terms, the generally accepted differences were not simply one of scope, but of applicability. A hypothesis is an idea, a testable idea about some given phenomena. It can be very narrow or fairly broad. Hypotheses are tested and from there they can be rejected, confirmed, or even modified. Over time, as the modifications grow less and less encompassing, the hypothesis becomes stronger and more well supported. Hypotheses can get rolled up into a Scientific theory. Now there rarely is a one for one relationship here, but the Theory is much more encompassing than a hypothesis and has undergone considerable testing and constant confirmation. In fact pretty much all the evidence supports a hypothesis, or hypotheses, before they can be considered a theory, or part of a theory. It's a process that's been defined time and time again.
Sure, the reality is less than absolute. New hypotheses can come out of existing theories, theories can be made up of multiple theories and hypotheses. But as an explanation or terminology, I think the complicated reality only confuses the issue. Before you can appreciate the complex reality, you have to understand the basics of the terminology.
Now a law is a manifestation of a theory/hypothesis. It's much more narrow than either a hypothesis or a theory. It's an application under a very specific set of parameters. It's often expressed mathematically, but that's not always true.
What is true is that while hypotheses can become theories, they never 'grow-up' to be laws. That's a common Creationist myth about science. I actually have heard people say things like 'If Evolution is so strong, why isn't it a law!" There I agree with Stephanie! What bothers me the most about how blurry she defined the terms, it opens the door for this exact sort of behavior. If we cannot firmly define our terminology, we tend to be fighting an uphill battle when other people misuse the terminology.
Out of curiosity, I searched the NCSE website for 'theory' and found this:
- Fact: In science, an observation that has been repeatedly confirmed and for all practical purposes is accepted as “true”. Truth in science, however, is never final and what is accepted as a fact today may be modified or even discarded tomorrow.
- Hypothesis: A tentative statement about the natural world leading to deductions that can be tested. If the deductions are verified, the hypothesis is provisionally corroborated. If the deductions are incorrect, the original hypothesis is proved false and must be abandoned or modified. Hypotheses can be used to build more complex inferences and explanations.
- Law: A descriptive generalization about how some aspect of the natural world behaves under stated circumstances.
Theory: In science, a well-substantiated explanation of some
aspect of the natural world that can incorporate facts, laws, inferences, and