Build/achieve/create things that are impressive and that work, or
Fix broken things that others can’t fix, or
Predict the future better than simple heuristics can (e.g. present trends will continue), or
Explain otherwise baffling things in a parsimonious way, in a way others can’t, then
They are not an expert. Even if they have fancy pieces of parchment on the walls of their office, and even if they have fancy titles.
As Barbara Oakley pointed out in the excellent “A mind for numbers”, claims of expertise not accompanied by proof are worse than acknowledged incompetence. At least the acknowledged incompetent will not act on a false basis of competence.
Also, not all ‘experts’ are actually expert.
If they can’t
Build/achieve/create things that are impressive and that work, or
Fix broken things that others can’t fix, or
Predict the future better than simple heuristics can (e.g. present trends will continue), or
Explain otherwise baffling things in a parsimonious way, in a way others can’t, then
They are not an expert. Even if they have fancy pieces of parchment on the walls of their office, and even if they have fancy titles.
As Barbara Oakley pointed out in the excellent “A mind for numbers”, claims of expertise not accompanied by proof are worse than acknowledged incompetence. At least the acknowledged incompetent will not act on a false basis of competence.