The solution he proposes shows how much quotas could change Brazilians' sense of who they are: in doubtful cases a commission would verify students' racial identity, overthrowing the idea that a person's race is what he says it is.

ECONOMIST: Race in Brazil

By looking at large numbers of paintings that are universally believed to be authentic, Dr Farid hopes to be able to examine doubtful cases with confidence in the future.

ECONOMIST: Finding forgeries: Different strokes | The

In some cases the surgery itself is of doubtful value.

FORBES: Is elective surgery overdone?