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Most people, when first encountering the Liar Paradox, react in one of two ways. One reaction is not to take the Paradox seriously and say they will not reason any more about it. - Dowden, IEP article 'Liar Paradox'

Why is this? In view of its revelation on semantic closure in language, the challenge it poses to formulating a theory of truth and so forth, it seems utterly bewildering that anyone would take the Liar Paradox so lightly. Does anyone know any reference on why this is?

Context: If it helps, I am currently writing my thesis on dialetheism, so naturally I have to discuss why the Liar is important and why it warrants revising the law of non-contradiction.

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    He goes on to say that the "more popular reaction is to say the Liar Sentence must be meaningless". Is it really surprising that at least a minority of people do not see semantic closure and theories of truth as burning issues in their lives? I suspect they would have the same reaction to the string theory or to the Riemann hypothesis. But there is even a philosophical attitude that considers such paradoxes to be overhyped by logicians, and an artifact of their own abuse of ordinary language. Wittgenstein's "bewitchment of our intelligence by means of language" to be cured by his therapy.
    – Conifold
    May 3 at 7:07
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    One clear reason why paradoxes are taken so lightly is that it has more to do with Psychology & Rhetoric than Philosophy itself. Case in point the paradox would fail to be a paradox if we use different sentences in place of what we already have been given. Suppose we use synonyms for most of the words. Would the paradox lose its impact? Surely we can represent the same propositions with different wordings without changing the proposition itself. Special words were chosen for paradoxes to work. This is no accident. Changing the wording alone can kill the effect of the paradox.
    – Logikal
    May 3 at 12:01
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    Some may feel that propositions which are just about the truth-value of propositions and don't refer to any "real" entities should not be judged true or false, even where there's no paradox--see the example with the 3 switches and the example with the 3 people saying some others are lying on p. 26-27 of ch. 1 of Maudlin's Truth and Paradox & the comment on p. 27 'their little conversation has no content at all beyond referring to one another: what could be the grounds which make any of their claims true or false?'
    – Hypnosifl
    May 3 at 15:12
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    Certain philosophical ideas, imo, reek of "tricky superficiality". Liar paradox is one of them... ontological argument is another. I think the average person is very good at recognizing these kinds of arguments and decide they are not worth the time. They feel less about substance, more about wordplay. May 4 at 0:49
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    Most people are naturally deflationary towards language sentences, imho this may be a major reason... May 4 at 3:06
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To give you an example (a few more are cited in that paper of Weaver) those who hold it as unimportant generally do not write in usual academic venues about it, but it goes something like:

As the logician Arnon Avron puts it

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 . . . 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 fact if you follow the FOM discussion referenced, Avron goes on to say:

On Sun, Jul 19, 2015 at 05:07:10PM -0500, Nik Weaver wrote:

So you would agree that the liar sentence is not true?

My immediate answer is: No, I do not agree, because a bunch of words should be a meaningful sentence before it deserves the honor of asking whether it is true or not.

However, you might have intended to use the above words in order to ask a question which is different from that which I have just answered. (Thus intuitionists use the word "not", but the meaning they attach to it - whatever it is - is not the meaning that ordinary people attach to it.) So in order to find out what is the real intended meaning of your question, and then answer it accordingly, please tell me your answers to the following questions:

  1. Would you agree that Eiffel tower is not true?
  2. Would you agree that the number 7 is not yellow?
  3. Would you agree that the liar sentence is not yellow?
  4. Would you agree that "This sentence is true" is not true?
  5. Would you agree that 1/0 is not less than 7, and also not greater than 7?
  6. Would you agree that the liar sentence is not less than 7, and also not greater than 7?

In a later post Avron mentions that:

the liar is known for two thousands years or so, and (as far as I know) mathematicians never really care about it. The story was completely different when they faced Russel's paradox (or the other "logical paradoxes") - and for good reasons.

So that's generally the gist of the "opposition" to it.

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Appearances being deceiving here, consider that the liar sentence (and the truth-teller sentence too, for that matter) could only be as they say they are in the effective equivalent of a private language. This can be illustrated in terms of the idea of the One True Fact: if the liar sentence is true by corresponding to a fact, the way this fact would exist would keep it "apart from" all other facts, all of those being united apart from it. So if true, its truth would be separated from all other truth. Why think, then, that its ability to consistently assume inconsistent truth-values has anything to do with the rule of consistency for the other truths?

I admit, this is just my view of the matter; I don't know (and I am surprised that I don't, given how near and dear to me this topic is!) why anyone else thinks the liar paradox isn't "dangerous," so to say. There is a "deflationist" approach to the liar paradox that might be relevant and worth looking into, that's the best outside reference I can make, here.

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  • You seem a staunch correspondent approach proponent towards language sentences. I guess most people are naturally deflationary... I somehow agree with u that deflationary may be not ideal and useful compared to correspondent. May 4 at 3:12
  • At the very least, consider, "This sentence doesn't correspond to a fact," in place of, "This sentence doesn't map to TRUE"? May 4 at 21:37
  • Certainly correspond will be much better than map since the former vividly implies the latter and fully satisfies deflationists while keep others like yourself endurable... May 6 at 3:29

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