The Real Meaning of Common Sense

“Common sense is not so common” says Voltaire (although the quote I found translated from Dictionnaire Philosophique was actually ‘It is sometimes said, common sense is very rare’ but the sentiment remains the same). Rather than a common sense observation, I believe it was a play on words with its true meaning lost to the slow evolution of language.

While ‘common’ means ‘occurring, found, or done often; prevalent’ in many contexts, the word means ‘shared by, coming from, or done by more than one’ as well. The modern interpretation of ‘common sense’ relying on the first definition seems boring to me, but the second?

That ‘common sense’ means ‘a sense (of reality) shared by two or more people’ which instantly offers us some insights. When someone says that an idea is ‘common sense’ that means the view is shared by their peers, often assumed and unexamined. When someone rejects a notion as ‘common sense’ that person simply does not share that view. Voltaire’s quote transforms from a quip about how foolish people are to wordplay about how little people have in common.

Appeals to ‘common sense’ are both ineffective and, sadly, common. The rejection of those appeals does nothing to further a topic. You do not have to examine your own assumptions to reject someone else’s! Rather than a discussion about the issue, people bicker about what is (and isn’t) ‘common sense’. Why?

Because using ‘common sense’ to mean ‘a sense (of reality) that is prevalent or widespread’ allows people to paint their opposition as the strange one who needs to defend their deviation from the social norm. You can demand your opposition justify their oddity rather than approach the topic as equals.

Rather than falling for the rhetorical trap, once you recognize a view or assumption is not shared between you and someone else, discard ‘common sense’ entirely. Focus on what assumptions both parties are making and why those assumptions aren’t shared. If anyone tries to force you to defend your position because their position is supposedly ‘common sense’ or normal…

It’s normal to be wrong. And common sense dictates anyone who cannot defend their position adequately is probably wrong.