Families, caskets and suitors
Back when the Bellini and Cellini families were still alive, an Italian noblewoman decided to test the intelligence of a prospective suitor, as she did not wish to marry a dullard. They had already fallen in love with each other, and she told him that she would hide a portrait of her in one of three caskets, all of which were made by either Bellini (who always inscribes true statements) or Cellini (who always inscribes false statements.) The noblewoman did not want the sons involved, as caskets made by the masters themselves were worth far more. So all three caskets were made by either Bellini himself or Cellini himself. If the suitor could find the casket with her portrait, he could marry the noblewoman. She clearly specified that the portrait would be in exactly one -- no more, no fewer -- of the caskets.
When he arrived, he was confronted with three large caskets made of the finest gold.
Casket A read: "The portrait is in here."
Casket B read, "The portrait is in here."
Casket C read, "At most one of these three caskets was fashioned by Bellini."
To win the noblewoman, which casket should he choose?