Re: more on logical issues

[Jorge Llambias <jorge@PHYAST.PITT.EDU>]

Steve Hazel:

> >  All even prime numbers greater than three are multiples of 27.
> >  Yes, indeed there are no even prime numbers greater than three.
> >
> >Is that really bad English?
>
> While the English syntax is not flawed, the logic may be.  The basic question
> here, I think, is whether or not it is logical to say that a nonexistant thing
> or nonexistant things ("even prime numbers greater than three") can be given
> properties ("are multiples of 27").

That's not really the point I want to make. The logical question is whether
a universal quantification need have referents. If you say "nothing is
an even prime number greater than three" you are not giving a property
to "nothing", even though the English syntax would seem to suggest it.
Similarly, if you say "all even prime numbers greater than three are
multiples of 27" you are not giving a property to "all even prime numbers
greater than three", simply because there are none.

Jorge