One of the most annoying things you can hear is “use common sense.”
But according to new research, the saying may not carry much weight.
Experts have discovered that “common sense,” often claimed to be universal, is unique to each individual.
And what defines “common sense” actually varies considerably from person to person.
The University of Pennsylvania team collected 4,407 statements, each of which – at some point – claimed to represent common sense knowledge.
It may seem like common sense to some, but researchers found that people couldn’t agree on whether “Planet Earth is round” is considered common sense
Examples include ‘Triangles have three sides’, ‘A battery cannot supply electricity forever’, ‘Alcohol should be restricted for fans during sports matches’, ‘Avoid close contact with people who are sick’, ‘If you want to play a game play ‘guitar, you need to take lessons’ and ‘Planet Earth is round’.
They then asked more than 2,000 people to rate how much they thought the claims were “common sense.”
They found that the perception of which statements represented “common sense” varied significantly between people.
And overall, relatively few statements met the traditional definition of common sense, as “knowledge that everyone takes for granted,” because not many people could agree on them.
The team said that at most only a small portion of people agreed on which statements represented common sense.
The researchers found that people’s perceptions of whether statements such as “A battery can’t supply power forever” naturally varied widely, and very few statements met the criteria of common sense.
Factors such as age and gender did not appear to affect how people perceived their sanity, she added.
Writing in the journal Proceedings of the National Academy of Sciences, the researchers said: ‘Although common sense is often portrayed as universal, paradoxically it is also often claimed that it does not exist.
‘Here we resolve this puzzling situation by introducing a formal methodology to empirically quantify common sense at both the individual and collective levels.
‘We show that common sense varies considerably by type of statement, but is most consistent with clearly formulated, factual statements about physical reality.
‘We also find a limited presence of collective common sense, which undermines universalist claims and supports skeptics.’