to be as dumb as [a stick, a sock, a bag of rocks, a box of rocks, a mouse, a
statue, any oyster]
Contexto
There was once upon a time a merchant name Ibrahim, who
met failure in every venture he undertook, until all that was left of a one-time great fortune
was ten pieces of gold and a daughter named Katoura, who was as beautiful as a rose, but
who had been as dumb as a stone from her birth.