Extremists are everywhere...

mathematical extremists,
'liberal'  (Caucasian white middle-class) extremists,
nuclear-physics extremists,
bureaucratic extremists,
academic extremists,
atheist extremists,
pharmaco-medical extremists,
extreme capitalists
extreme misanthropists
hygiene-extremists who change their underwear
more than once a week,
those with extreme wealth,
those in extreme poverty
and even (of course) extreme anti-extremists like me.