Judith A. Erickson wrote:

>This may be a memorable quote relevant to this discussion:
>
>"Common sense is not so common." 
>Voltaire
>  
>

Indeed, what Voltaire said was "Le sens commun n'est pas si commun."

Common sense does not lproduce understanding that liquid nitrogen will 
cause oxygen to condense in a vessel left immersed in the liquid 
nitrogen.  (K. Barry Sharpless -- Nobel Prize for Chemistry 2001 or 2002 
-- lost an eye when he was a first year professor, to an nmr tube into 
which a grad student had unwittingly condensed and sealed oxygen.)

Common sense does not lead to an understanding of why a container of 
hexane, in a "lab safe" freezer, covered only with parafilm, would 
release enough vapor to blow up the freezer when the door is opened.  
(But it's cold in there; the vapor pressure is depressed, right?  And 
there shouldn't be a source of ignition because they've been removed...?"

Common sense does not tell a toddler not to reach up and pull on the pan 
handle sticking out from the stove top. 

Common sense doesn't tell people hearing a tornado warning alarm to take 
cover.  In many cases "common sense" tells them that the chances of 
being hit by a tornado are incredibly small, and they run outside to 
look at the sky.

las