Letter to the editor

16 April 2003

Dear Editor:

I was taken aback by the sub-heading on your page one Cal Day story in the April 10 Berkeleyan. The main headline asked “What’s the perfect Cal Day schedule?” while the sub-heading stated, “We think we’ve found it...unless of course we haven’t.” (www.berkeley.edu/news/berkeleyan/2003/04/09_calday.shtml)

This has the logico-grammatical form: P, unless Q. My understanding of such a sentence is that one who asserts it is saying that (s)he believes P to be true, but that if Q were found to be true then P would be false.

Applying this interpretation to your sub-heading, I infer that you (make believe) think that you’ve found the perfect Cal Day schedule, but that if it is found that you have not, then you would not think that you had.

Surely this flies in the face of normal patterns of belief. It could well happen that you’d found only the second-best Cal Day schedule, and yet you’d continue to believe that you’d found the best!

Don’t you agree?

Leon Henkin
Professor Emeritus of Mathematics
Member of the Group in Logic and the Methodology of Science

The Editor replies: Um, er — sure!