What do you call a person who has the ability to question and is curious about right things? As in someone who points out loopholes in an argument or the like.
Having a ready insight into and understanding of things.
A person to whom seeking out cavils in other people's statements and arguments is a source of rich joy is called:
- a pedant: a person who overemphasizes rules or minor details
- a pharisee: a sanctimonious, self-righteous, or hypocritical person
A person who questions other people's arguments and insists on finding his or her own answer can be called:
an explorer: a person who investigates unknown regions, not necessarily geographical
a pioneer: one who is first or among the earliest in any field of inquiry, enterprise, or progress
a pathfinder: a person who finds or makes a path, way, route, etc.
a trailblazer: a pioneer in any field of endeavor
All definitions are from The Comprehensive Online Dictionary