Saturday, February 20, 2010

Lather, rinse, repeat

There was recently quite a bit of interesting discussion about a Language Log post on the semantics of "this page intentionally left blank". Levi Montgomery posted that it reminded him of "the instructions to 'Lather, rinse, and repeat,' apparently ad infinitum." I was struck by this comment, because historically and upon careful thought, I don't find anything recursive about this statement.

Levi apparenty interprets this injunction as being of the form (A --> B --> return to A). This would indeed lead to infinite hair washing, with the user lathering and rinsing until the eschaton. But I rather have always interpreted the instruction as having the form ((1: A --> B); repeat 1). Thus there's no recursive loop, merely a second execution of the two events A and B. Or to phrase it another way, for me there is no way of deriving wide scope of repeat so that it includes lather, rinse, and itself. For me it can only apply to lather and rinse. I'd be interested to find out if more people get Levi's interpretation or mine, and why.


Levi Montgomery said...

I'm mostly just tagging this so I can subscribe to the comments, but yes, I do see it as "Begin here, do this, return to the beginning," although I don't of course. think they really meant for me to do it until I run out of shampoo. Why, that would mean I'd have to buy a lot of... Hey, wait a minute!

linguistlessons said...

I saw another commenter also posted a similar observation, and my wife also says that, if she were to take it literally, it implies that she should lather and rinse ad infinitum, so it seems I'm in the minority.

J. Goard said...

I'm with you. It explicitly says (i.e. not pragmatic repair, but straightforward semantics) to lather and rinse exactly twice.

To the other people: what formulations would or wouldn't create a loop?

(1) Lather. Rinse. Do it again.
(2) Lather. Rinse. Now repeat that.
(3) Lather. Rinse. Do this one more time.

Anonymous said...

Sorta vaguely related... have you ever heard of a quine?

SharonC said...

I've definitely always taken these sorts of things to mean 'repeat the actions just mentioned', not 'repeat ad infinitim'.

Velorek said...

It's interesting that in Spanish and Portuguese bottles the final part is "repetir si se desea/repetir se desejar" (repeat if you wish). So at least they let you decide before going into an endless loop he he.
I still think it's ambiguous. But our pragmatic interpretation resolves the matter.