to be dumb as [a sock, a bag of rocks, a box of rocks, a mouse, a statue, any
oyster, a stone]
Contexto
“I mean to say, the guy’s dumb as a stick and just as poor, too,
only he wants to keep playing, even after I got him mortgaging his granny’s grave and selling
the fillings in his teeth. So he’s bet every last tooth in his head, what’s he possibly got left to
give away?”