Het ei van Columbus
een oplossing voor een moeilijk probleem die simpel lijkt wanneer men de oplossing kent (= a solution to a difficult problem which seems simple once you know about it)
The statue of the egg of Columbus in Sant Antoni (Ibiza)
"Ja, dat is het ei van Columbus!"
The myth says that upon arrival home, Spanish noblemen told explorer Columbus they all could have find the route to present-day America.
As a response, Columbus supposedly took an egg in his hand and asked his fellow men who could let it stand vertically on the table. Everyone tried and no one succeed.
Then, Columbus took the egg, crushed the bottom and let it stand straight and still.
The 'ei van Columbus' is used to refer to the solution that seems obvious once you know about it.