March 30, 2007

In which I pick up, and drop, a bad habit

`Just in case' does not mean `if and only if'. You bring along an umbrella just in case it rains; two sets are of the same cardinality just in the case that there is a bijection between them. What a difference a definite article makes!

Where did I pick up the habit of using `just in case' when I really meant `just in the case that'? Possibly from one Andrew M. Bailey. Except that I was doing it two years ago, quite a while before I met AB. More likely this nasty little meme has been circulating throughout the Anglophone philosophical community for quite some time, and both AB and I contracted it that way.

2 comments:

bradley said...

I bring an umbrella if and only if it rains. What I like better is, "My car has an air bag just in case I get in an accident." Ah! My car does have an air bag! (I owe that to Tom Crisp)

Noumena said...

If you follow the first link, the linguistic claims that `just in case' is an almost strictly American idiom. So confusion is only unlikely when speaking to American philosophers.