Answer: Greek Mythology

In Greek mythology, Theseus was the mythical king and founder-hero of Athens, and a larger-than-life hero whose exploits explained the history of Athens and its role in Greek culture. Among his exploits are Herculian-like labors, foiling assassination attempts, and slaying the Minotaur in the Labyrinth of Crete.

Among the stories told about Theseus, the story of the Minotaur is likely the best known because of its inclusion in collections of Greek myths over the years. The key detail of the story is that Theseus sailed to Crete and the daughter of King Minos, Ariadne, fell in love with him. She, on the advice of the craftsman Daedalus (who built the Labyrinth for the king), gave Theseus a large ball of string to use as a guide in order to find his way out of the Labyrinth once he had slain the Minotaur.

The term for a ball of such string or yarn is “clew”, and for centuries, the word was used in English as such until it began to take on a new meaning: to provide insight or information that leads to a conclusion the same way the string in the Greek myth led Theseus to the conclusion of his ordeal in the Labyrinth. The spelling shifted from “clew” to “clue” and the old meaning was abandoned in favor of the new.

Painting by Jean-Baptiste Regnault/Wikimedia.