FOM: Pratt on imperatives

[John Mayberry]

	Vaughn Pratt has called attention to the important fact that 
not all sentences are used to convey facts. His example is instructive, 
and illustrates his point nicely.

If I say "Now construct the perpendicular to AC at B to intersect EF at 
G", I have surely spoken meaningfully, yet where is the truth in what I 
have said?

This is a point well made. But it never occurred to me to deny that 
there are sentences that are used for other purposes than conveying 
facts. There are interrogatives as well as imperatives, and they do not 
admit of being pronounced true either. But if *no* declarative sentence 
can express a truth, I cannot see what the meaning of such  sentences 
might be. And if declarative sentences don't have meanings, where does 
that leave imperatives and interrogatives?
	Suppose I try to carry out the command in Pratt's example by 
drawing a line L. Then I might say

The line L is perpendicular to the line AC at B and intersects EF at G.

Now if *no* sentence of that form *can* be said to be true, whatever 
could the original command have *meant*?
	When I said that if there is no such thing as speaking truly 
then there is no such thing as speaking meaningfully, I thought I was 
pointing out the obvious, not putting forward some subtle point in 
theoretical semantics.
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John Mayberry
J.P.Mayberry at bristol.ac.uk
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