digamma.net - notes

In another life, I was an aspiring classicist. (Hence my pseudonym.) I draw on that experience when I say that Matthew Yglesias, great blogger and journalist that he is, should stop abusing the Latin language:

So let’s concede ad arguendo (though I hasten to add – only ad arguendo) that John Kerry has no better idea than George W. Bush of how to clean up the mess that George W. Bush and George W. Bush’s national security team have made in Iraq.

That’s the same grammatical error twice (I hasten to repeat – twice) in the same sentence.

The proper expression is arguendo. It’s the dative case, expressing purpose, and translates perfectly to the English expression “for the sake of argument.” The preposition ad takes an object in the accusative case, which would be arguendum, and in fact the phrase ad arguendum appears in Paul’s second epistle to Timothy. But ad arguendo is just plain wrong.

This has been a pedantic correction of a writer far superior to me.