I know originally it's a Math term. But what does "low common denominator" mean in the following sentences?
"From a rational public policy perspective,
satisfaction is not only a
low common denominator, it is dangerous."
"Unlike typical Where to Find Birds books, which tend to be written to a
low common denominator, Wheatley's book incorporates the latest field reports from leading British and American experts on South American birds."
" (the wines) had, in its inimitable way, collectively reduced our zeitgeist to a
tribal low common denominator." (--and, why "tribal"?
)