In the expression "this sentence is false", which sentence is "this" referring to?
There are several possibilities.
Possibility two
It could be referring to itself. In this case, the sentence "this sentence is false" means that the expression "this sentence" is false. But this is meaningless, and is similar to saying "this house" is false. — RussellA
In the expression "this sentence has five words", which sentence is "this" referring to?
Possibility 2
It could be referring to itself. In this case, the sentence "this sentence has five words" means that the expression "this sentence" has five words. Of course it's false, but per your reasoning it appears meaningful. — EricH
Mark Twain is Samuel Clemens.
— TonesInDeepFreeze
Open to doubt. — RussellA
is this something X in the world Samuel Clemens, or has the something X in the world been named "Samuel Clemens"? — RussellA
As naming something in the world "a cat" doesn't make that something a cat, in that I could name a horse "a cat", naming something in the world "Samuel Clemens" doesn't make that something Samuel Clemens. — RussellA
My naming that tall tower in Paris in the 7th Arr of Champs de Mars "a kangaroo" doesn't make that something in the world a kangaroo. — RussellA
Giving something in the world a name doesn't make that something into what has been named. — RussellA
Just because something in the world has been named "Samuel Clemens", that doesn't mean that Samuel Clemens exists in the world. — RussellA
Although "Samuel Clemens" and "Mark Twain" exist in language, as neither Samuel Clemens nor Mark Twain exist in the world, then it is not correct to to say that Mark Twain is Samuel Clemens. — RussellA
"The Pentastring" is a name for the expression "This string has five words".
— TonesInDeepFreeze
No problem, setting aside what "this string has five words" means, and treating it as a set of words such as "a b c d e", and ignoring any meaning that it may or may not have. — RussellA
The Pentastring is "This string has words".
— TonesInDeepFreeze
Open to doubt. — RussellA
As before, my assumption has been that because "This string has five words" is in quotation marks, this means that "This string has five words" is an expression in language, and because the Pentastring is not in quotation marks, this means that the Pentastring is something that exists in the world.
The problem is, you are not saying that "this string has five words" is the name of the Pentastring, you are saying that "this string of five words" is the Pentastring. — RussellA
If A is B then B is A. If "this string has five words" is the Pentastring, then the Pentastring is "this string has five words". — RussellA
How can an expression in language be something in the world? — RussellA
How can "London" be a city? — RussellA
This is not a side issue, as crucial to your argument that a self-referencing expression can be meaningful. — RussellA
"This string has five words" was named "The Pentastring", and "This string has five words" is the Pentastring. — TonesInDeepFreeze
"London" is a city. (false - "London" is a word, not a city) — TonesInDeepFreeze
You think Mark Twain was someone other Samuel Clemens? — TonesInDeepFreeze
That baby was named "Samuel Langhorne Clemens" and was Samuel Clemens — TonesInDeepFreeze
the question was about the truth of the words - this sentence has five words.
The question was not about the truth of the words - "this sentence has five words". — RussellA
As regards "this sentence has five words", it all depends on what "this sentence" is referring to. — RussellA
If it is self-referential, then it is meaningless — RussellA
"this sentence" is referring to "this sentence". — RussellA
"This string has five words" was named "The Pentastring", and "This string has five words" is the Pentastring.
— TonesInDeepFreeze
No problem that "this string has five words" was named "the Pentastring"
I agree when you say:
"London" is a city. (false - "London" is a word, not a city)
— TonesInDeepFreeze
Then how can "this string has five words" be the Pentastring? — RussellA
You think Mark Twain was someone other Samuel Clemens?
— TonesInDeepFreeze
My problem is:
That baby was named "Samuel Langhorne Clemens" and was Samuel Clemens
— TonesInDeepFreeze
Sense and reference
"Mark Twain" and "Samuel Clemens" both refer to the same thing in the world, although the names have a different senses — RussellA
in that "Mark Twain" was an author whereas "Samuel Clemens" wasn't. — RussellA
As regards reference, "Mark Twain" and "Samuel Clemens" are both referring to the same thing in the world. Let this something be both Mark Twain and Samuel Clemens. In this event, Mark Twain is Samuel Clemens. — RussellA
As regards sense, "Mark Twain" is referring — RussellA
That "Samuel Clemens" is Samuel Clemens would give rise to logical contradictions. — RussellA
If person A, born in Hannibal, is named "Samuel Clemens" then that person becomes Samuel Clemens. If person B, born in New York is also named "Samuel Clemens" than that person also becomes Samuel Clemens. In logic, the law of identity states that each thing is identical with itself, in this case, that Samuel Clemens is Samuel Clemens. But this means that person A born in Hannibal is person B born in New York. Something is wrong. — RussellA
A group of Modernists name a painting "good", meaning that the painting is good. A group of Post-Modernists name the same painting "bad", meaning that the same painting is bad. But this means that good is bad, which breaks logic. — RussellA
"Mark Twain" and "Samuel Clemens" exist in the mind not the world. If there were no minds, then neither "Mark Twain" nor "Samuel Clemens" would exist. — RussellA
How can "London" be a city?
— RussellA
What? "London" is not a city. No one said it is. — TonesInDeepFreeze
"This sentence has five words" is the sentence in question. It is true if and only if "This sentence has five words" has five words. — TonesInDeepFreeze
"This sentence has five words" is true IFF "this sentence has five words" has five words.
If this were the case, then it would follow that:
"New York is in France" is true IFF "New York is in France" has five words. — RussellA
"This sentence has five words" is the sentence in question. It is true if and only if "This sentence has five words" has five words. — TonesInDeepFreeze
"New York is in France" makes no mention of the number of words in "New York is in France". — TonesInDeepFreeze
I agree that
1) "snow is white" is true IFF snow is white
2) "New York is in France" is true IFF New York is in France
3) "This sentence has five words" is true IFF this sentence has five words — RussellA
The problem with 3) is what exactly are "this sentence" and (this sentence) referring to? — RussellA
in a non-self-referential case, "this sentence" could be referring to the sentence "New York is in France" — RussellA
(this sentence) could be referring to (New York is in France).
The non self-referential case is meaningful. — RussellA
in a self-referential case, "this sentence" could be referring to the sentence "this sentence has five words", and (this sentence) could be referring to (this sentence has five words). The self-referential case is meaningless. — RussellA
The problem with the self-referential case, is that the content of a sentence contains no information about the form of the sentence.
The content of the sentence "this sentence has five words" is that "this sentence has five words". The form of the sentence "this sentence has five words" is that the sentence "this sentence has five words" has five words. — RussellA
The content of a sentence can say nothing about the form of the sentence. It cannot self-refer. — RussellA
As the sentence "New York is in France" says nothing about how many words are in the sentence "New York is in Paris, the sentence "this sentence has five words" says nothing about how many words are in the sentence "this sentence has five words" — RussellA
I agree when you say:
"New York is in France" makes no mention of the number of words in "New York is in France".
— TonesInDeepFreeze
From the same logic, "this sentence has five words" makes no mention of the number of words in "this sentence has five words". It makes no mention of the fact that "this sentence has five words" has five words. — RussellA
Any similarity in expression is purely accidental. — RussellA
Content cannot refer to its own form. — RussellA
With the sentence "Jack is tall", the sentence makes the claim that Jack is tall...................With the sentence "This sentence has five words", the sentence makes the claim that "This sentence has five words" has five words. — TonesInDeepFreeze
Yes? And the sentence would be false. — Michael
"Jack is tall" is making the claim that "Jack is tall" is true IFF Jack is tall — RussellA
1. This sentence contains five words.
2. This sentence contains fifty words.
(1) is true and (2) is false. It's not complicated. I don't understand the problem you have. — Michael
1. It is raining.
2. "it is raining" is true iff it is raining.
(1) and (2) do not mean the same thing. (1) is true iff it is raining but (2) is true even if it isn't raining. — Michael
If "this sentence" is referring to "this sentence contains fifty words", then this is a case of self-reference, and being a case of self-reference is meaningless. — RussellA
In that event, this sentence, ie the sentence "this sentence contains fifty words", contains fifty words. — RussellA
"This sentence has five words" is true IFF this sentence has five words — RussellA
No it’s not. — Michael
No it doesn’t. It contains five words and so is false. — Michael
That you blatantly skip this point over and over is intellectual dishonesty. — TonesInDeepFreeze
That's why there is a SEP article on the Liar Paradox. — RussellA
But you weren't talking about the liar paradox. You were talking about the sentences "this sentence contains five words" and "this sentence contains fifty words". These two sentences are meaningful, with the first being true and the second being false. — Michael
You say that the sentence "this sentence contains fifty words" is false.
But you don't know that. — RussellA
If "this sentence" is referring to itself, ie, "this sentence contains fifty words", then both the SEP and IEP discuss the problems of self-referential expressions.
The SEP article on the Liar Paradox starts with the sentence "The first sentence in this essay is a lie"
The IEP article Liar Paradox talks about "this sentence is a lie" — RussellA
... self-reference is not a sufficient condition for paradoxicality. The truth-teller sentence “This sentence is true” is not paradoxical, and neither is the sentence “This sentence contains four words” (it is false, though).
there is insufficient information [...] to know which sentence "this sentence" is referring to — RussellA
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