[FOM] The liar "revenge"?

Arnon Avron aa at tau.ac.il
Sun Jul 19 15:41:01 EDT 2015

I started today to read Weaver's new book "Truth & Assertibility",
and already at the very first page I came across
an argument that amazed me. It is not that it was the first time
that I encounter that argument, but it is the first time
I see it taken seriously by someone that I really respect (I hope
that the rest of the book does not depend on it!). It
runs as follows:

"The first impression most people have about the liar sentence
is that it is completely meaningless. But surely a meaningless
sentence cannot also be true. So if it is meaningless
then in particular it is not true, and that is just what 
it says of itself... which would make it true. We have
reached a contradiction again."

Well, to me it seems that Weaver could have shorten the 
"argument" by saying that if the liar sentence is meaningless,
then since it is meaningful we have reached a contradiction again...
Surely a meaningless sentence cannot say anything about
anything, in particular not about itself (or anything else). So
relying on what "it says of itself" depends on taking 
for granted that it is meaningful. Therefore the above  argument
is hopelessly circular!

I do wonder now if I am missing something here, and if so -
what can it possibly be.

Needless to say, for me the "liar sentences" of all types
are indeed completely  meaningless, which is why I was never bothered
by them (in contrast to the so-called logical paradoxes).

Arnon Avron

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