Myth #4. Evolution Is Just a Theory
Yes! Evolution is a theory! There is no doubt that it fits the definition. The problem lies with the common misconception of what that definition is. How many times have you heard someone say "I have a theory about that"? It's fairly common to use the word "theory" where it doesn't actually fit.
A scientific theory is a well-established principle based upon repeated testing and observation. It is used to explain things in the natural world. In addition to repeated observations, a theory includes laws, predictions, facts, and widely accepted and tested hypotheses. A theory is often made up of multiple hypotheses. Some examples would include plate tectonics, atomic theory, Stockholm syndrome, architecture, Theory of relativity, and yes, Theory of evolution.
A hypothesis is a specific prediction about an expected outcome to a test or study. For example, if I use an appropriate amount of fertilizer on a plant, the plant will grow to be bigger than a plant that doesn't receive fertilizer. A hypothesis is essentially an educated guess. A hypothesis, by its very definition, does not deserve equal weight to a theory.
A good hypothesis is something that can be tested. To be considered "good", we have to be able to measure either the cause and effect or the correlation. Intelligent design doesn't necessarily make a good hypothesis, but if we use a loose definition of hypothesis, we can put intelligent design in there.
Scientific theories are not guesses. A hypothesis is a speculative guess that requires testing. Evolution has achieved the label of "theory". Intelligent Design has not.