Science Has Its Beliefs Too

It’s just that, unlike religious beliefs, they’re rational

“The Demon-Haunted World: Science as a Candle in the Dark”

“Evolution is just a theory!”

How many times have I seen that said on Twitter? A lot. The irony of the assertion has to do with the writer not realizing that theory has two meanings: in the everyday world of average people where the colloquial use of the word means belief or opinion, and the specialized use of the word within science to mean an explanation of something. It’s a fact that certain germs cause disease, and the germ theory of disease explains that fact. No physician “believes in” tuberculosis; no astronomer “believes” Earth orbits the sun; no evolutionary biologist “believes in” evolution.

Science proceeds with hypotheses that are based on a clue or a set of disparate clues that haven been put together into a cohesive whole even if some information may still be missing. Nobody knows how life started, though some people believe life began on Mars, while others hold to a hot springs hypothesis as a possible originating point for life. Neither belief is outlandish so long as some elements are in place that give the hypothesis some credibility.

Some “beliefs” are understandably stated as blanket assertions: “Alligators don’t live at the North Pole.” No one needs to visit the North Pole to confirm this fact. All you have to do is piece together two established facts to understand why the assertion is true: the nature of the environment at the North Pole and the nature of an alligator’s habitat. (Hint: There are no swamps or freshwater rivers at the North Pole.)

And then there is the scientific belief that sounds like sheer imagination: “I believe life exists elsewhere in the universe.” In lieu of evidence to back up this statement, is there any good reason for asserting it? Yes, there is: the existence of carbon. Or to quote National Geographic: “Carbon is an essential element for all life forms on Earth. Whether these life forms take in carbon to help manufacture food or release carbon as part of respiration, the intake and output of carbon is a component of all plant and animal life.” So when a scientist says life may exist elsewhere, the belief is grounded in an acceptable syllogism: carbon is a necessary element for life; carbon exists in abundance in the known…