Common Sense versus Law

I wrote a Supreme Court amicus brief about commercial speech.  Its gist was skepticism about common sense, specifically, the “common sense” that distinguished commercial speech (i.e., advertising) from all other forms of protected speech.  I find so much and so little to commend common sense. 

The strengths of common sense: it suggests an early absolute, and therefore provides a foundation for which no further inquiry is necessary; it purports to bind the community in what is obvious; it taps into common experience and therefore becomes a given that can be parlayed into legal propositions; it provides an easy starting point for postulates that need no examination; it provides a straightforward decision when strict logic would require multiple (and difficult) steps to reach that decision.

The dangers of common sense: it solidifies an early prejudice; it defies critical examination because it is commonly embraced; it permits a postulate that is not sufficiently examined; it masks as obvious when it is not, but carries the unassailable weight of obvious; it permits decision-making that need not be defended.

On balance now, I support the use of “common sense” to decide cases.  There will be mishaps, but most often common sense will be a shortcut to shared understanding and efficient adjudication. 

But I can’t help inquiring carefully into the sense that is common.