This 16th century painting by Hieronymous Bosch depicts a quack surgeon plucking the "stone of folly" from a fools's head while a monk assists and a nun looks on vacantly. The surgeon's funnel is symbolic of fraud, his jug a symbol of Satan. Bosch was satirizing the ignorance of his day, when surgeons commonly deluded patients into believing such stones caused madness.
The pitcher in the monk's left hand presumably contains
some manner of inebriant, being employed here as an
anesthetic. One can hope that this scene might serve
as a reminder to the patterns community not to fall
prey to the sorts of hype, hucksterism, and charlatanism
that have afflicted other emerging disciplines as they've
found their ways into the limelight.