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Name: scollins
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

I need good definitions for the following terms: hypothesis, theory, law. I teach high school biology and our textbook states that scientific laws - universal explanations of phenomena - do not exist in biology. This leads to the inevitable student comment that everything I have taught them is "just a theory."

A hypothesis is a formal generalization, or tentative explanation for a set of data, or a group of observations. A hypothesis allows scientists to design specific, do able experiments to test whether the tentative explanation will work on a new set of observations on the same subject. A theory is a hypothesis that has been extensively tested to the point of being generally accepted as true. Sometimes we use the term "law" for a very extensively tested theory, especially one that has an equation, or quantitative rule used to predict the outcome in a certain situation, e.g., the Law of Gravity. It is a common error to assume that when a scientist uses the term "theory" that he or she means something which is still not yet believed or accepted. This is not true. The word is used for almost all principles because we do not really understand anything completely. We speak of the theory of evolution, for example, even though virtually every reputable biologist in the world believes that evolution is a proven law. However, some very important details are still being debated and tested, so the word theory is used. Scientists are always testing.


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