Theory v. Law v. Hypotheses

While verbally sparring with a friend online earlier, I stumbled upon a great little site that presents a very clear and concise definition of hypotheses, scientific law and scientific theory.  As anyone who's had these kinds of arguments on a regular basis knows, creationists, climate change deniers and the anti-science crowd in general all love to argue that a theory is really just an idea, not a concrete fact.  Evolutionary theory, quantum theory, chaos theory, string theory, climate change theory and all the rest are mere possibilities and should be treated as such, they claim.  Why?  Because they end in "theory."

Here's a great little explanation from the Wilstar site that helps to explain what a scientific theory actually is:

A scientific law is like a slingshot. A slingshot has but one moving part--the rubber band. If you put a rock in it and draw it back, the rock will fly out at a predictable speed, depending upon the distance the band is drawn back.


An automobile has many moving parts, all working in unison to perform the chore of transporting someone from one point to another point. An automobile is a complex piece of machinery. Sometimes, improvements are made to one or more component parts. A new set of spark plugs that are composed of a better alloy that can withstand heat better, for example, might replace the existing set. But the function of the automobile as a whole remains unchanged.


A theory is like the automobile. Components of it can be changed or improved upon, without changing the overall truth of the theory as a whole.

Keep this analogy in mind the next time you have to defend evolutionary theory in the public school system (or something along those lines).