Common Sense May Not Be Commonly Shared, Sociologists Find

Common sense might not be so common after all, new research has found.

What one person might consider common sense might be very different to someone else, a new study in the journal Proceedings of the National Academy of Sciences reveals.

Common sense—classified by the researchers as things we know to be true without really knowing why—is much more unique to individuals than we first thought.

“Common sense, while often portrayed as universal, is paradoxically also often claimed not to exist. Here, we resolve this puzzling situation by introducing a formal methodology to empirically quantify common sense, both at individual and collective levels,” the authors wrote in the paper.

This paper attempts to resolve the ambiguity of traditional definitions of common sense using an analytical framework, and figure out how common certain common sense beliefs are.

“The notion of common sense is invoked so frequently in contexts as diverse as everyday conversation, political debates, and evaluations of artificial intelligence that its meaning might be surmised to be unproblematic,” the authors wrote.

“Surprisingly, however, neither the intrinsic properties of common sense knowledge (what makes a claim common-sensical) nor the degree to which it is shared by people (its “commonness”) have been characterized empirically.”

The researchers—from the University of Pennsylvania—used a case study of 4,407 claims of common sense from several sources, and asked more than 2,000 people to rate how common-sensical each claim was.

These claims included things like “perception is the only source of knowledge, what is not perceived does not exist;” “rudeness is the weak man’s imitation of strength;” “triangles have three sides;” “numbers don’t lie, we should always trust the math;” “all human beings are created equal;” and “avoid close contact with people who are ill.”

“A key contribution of our framework is that it resolves the logical circularity that is inherent to traditional definitions of common sense, which equate common sense with self-evident truth without specifying what makes a given claim self-evidently true or to whom it ought to be self-evident,” the authors wrote.

“By breaking this circularity, our framework is capable of answering two fundamental questions about the nature of common sense: first, which attributes of claims (or people) make them more or less common-sensical; and second, how “common” is common sense with respect to any given population?”

They found that between individuals, things considered to be common sense varied significantly across a variety of claims, and at the collective level, few claims matched the definition of common sense as being obvious to everyone.

“We show that common sense varies considerably across types of claims, but aligns most closely with plainly worded, factual claims about physical reality; in contrast, [it] does not vary much across different types of people. We also find limited presence of collective common sense, undermining universalist claims and supporting skeptics.”

The researchers hope that their analytical framework may be helpful in future studies involving social science and artificial intelligence.

“We anticipate that this tool will be used in larger-scale studies in the future, furthering our collective understanding of common sense and its role in both human and artificial intelligence,” they wrote.

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