Video:Defining Scientific Hypothesis, Theory and Law

Transcript:Defining Scientific Hypothesis, Theory and Law

Words have precise meanings in science. For example, 'theory,' 'law,' and 'hypothesis' don't all mean the same thing.

Definition of Scientific Hypothesis

A hypothesis is an educated guess, based on observation. Usually, a hypothesis can be supported or refuted through experimentation or more observation. A hypothesis can be disproven, but not proven to be true.

Definition of Scientific Theory

A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing. A theory is valid as long as there is no evidence to dispute it. Therefore, theories can be disproven.

Basically, if evidence accumulates to support a hypothesis, then the hypothesis can become accepted as a good explanation of a phenomenon. One definition of a theory is to say it's an accepted hypothesis.

Definition of Scientific Law

A law generalizes a body of observations. At the time it is made, no exceptions have been found to a law. Scientific laws explain things, but they do not describe them. One way to tell a law and a theory apart is to ask if the description gives you a means to explain 'why'.

As an example, consider Newton's Law of Gravity. Newton could use this law to predict the behavior of a dropped object, but he couldn't explain why it happened. As you can see, there is no 'proof' or absolute 'truth' in science. The closest we get are facts, which are indisputable observations.

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