[FOM] A question about dialetheism and sorites

Sandy Hodges SandyHodges at attbi.com
Tue Nov 12 19:19:34 EST 2002

Suppose I (and only I) see a teacup of a borderline color, so it is both
blue and not blue (in the dialethetic view).   But I say only "The
teacup is not blue."    As I understand it, I have told the truth.
Although I also could have truthfully said "The teacup is blue," I am
not obliged to do so, any more than I am obliged to say "The teacup has
a handle."

Now suppose the saucer is definitely not blue, lacking any hint of
blueness.   I say: "The saucer is not blue."  I wish to be as
informative as possible about the blueness of the saucer.   However, as
far as my audience can tell,  I may be simply failing to say "The saucer
is blue."   For all they can tell, the saucer may be both blue and not
blue and I am telling them only part of what I know about it.   My
question is, is there any way, in a paraconsistent logic, for me to
assert that the saucer is not blue, and also not in the state of being
both blue and not blue?

In particular, does

~ Blue(saucer) & ~ ( Blue(saucer) & ~ Blue(saucer) )

have this meaning?
If the answer is that there is no way in first-order dialethetic logic
to say the saucer is not in the intermediate blue-and-not-blue state,
does it help any if I say "The saucer is not blue and 'The saucer is
blue' is not true."?

------- -- ---- - --- -- --------- -----
Sandy Hodges / Alameda,  California,   USA
mail to SandyHodges at attbi.com will reach me.

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