Metaphors can be culturally idiomatic. The German equivalent of coals-to-Newcastle is owls-to-Athens. I have to say that has nice classical ring to it, indicating die Jugend did not go to Gymnasium merely to eat their Mittagessens.

But I also think we have to distinguish metaphors from clichés. Poetry is full of odd sounding metaphors that enable English professors and teaching assistants to make a living explaining them to somewhat backward Freshpeople.

Newly minted metaphors that catch the ear can go on to become clichés. “Dead as a doornail” was coined by Charles Dickens to describe Marley in “A Christmas Carol.” More recently “dumb as a box full of rocks” quickly became a cliché as it so aptly characterized a broad swathe of management at a company where we once both worked.

One of my favorite fractured metaphors comes from Phyllis Schlafly (please stop groaning), who wrote about the “comparable worth” concept under the title: “Shall I Compare Thee to a Plumber’s Pay?”