Tue May 18 1999 12:25: The following is part of an email I just sent to Jake. I think it is of more general interest:
I thought of a great joke this morning. Or what would be a great joke, for some value of x.
Q: What's the difference between an x and an insect? A: Insects only eat their young.
The trouble is, I can't think of an x that makes sense in that joke. In fact, there may be no such x. The question is, does the absence of any such x make the joke less funny?
I was going to continue my search for some x that made sense, but then I thought of another joke that fits the same pattern:
Q: What's the difference between an x and a computer scientist? A: Computer scientists start counting from zero.
So now the question is, should I attempt to locate these xes, or should I just treat x as a Skolem constant and take this to be an altogether new joke form, in the spirit of "What's the difference between a duck?".