This sentence is false.

[Xenocide]

What do you guys think?

 

[SithDoughnut]

No it isn't. It's not true either. It's not a logical sentence.

 

[pgp_protector]

Liar paradox - Wikipedia, the free encyclopedia

 

[GrowingSmaller]

I thibnk that due to convention it is assumes that the sentence is an assetion, and therefore implicitly claims that it is true. So therefore it is more of a logical contradiction that a paradox when understood 'correctly'. Not sure if whatI have said stems from Frege's logic with it's assertion marks.

 

[GrowingSmaller]

More threads please xenocide.

 

[quatona]

What do you guys think?

Who cares? The sentence just points to itself and has no further implications, anyway.

 

[Eudaimonist]

What do you guys think?

Sentences aren't true or false. Claims are. What is the claim in that sentence?


eudaimonia,

Mark

 

[Tuddrussell]

False dichotomy, the implication is that a sentence must be either true or false. In reality it is merely incorrect.

 

[GrowingSmaller]

How is a sentence incorrect?

 

[Tuddrussell]

There are many way's which on a serntance can be incorrect, the op's is one.

 

[quatona]

Another one are spelling mistakes.

 

[Tuddrussell]

Also syntax, grammar, flow, tense, and any number of errors. The point is that they are not corrected, therefore it is incorrect. Intent is irrelevent.

 

[Eudaimonist]

I believe the claim was that the sentence which contains it is false.

Consider:

Claim: The earth is flat.

One can say in response "That claim is false". One could legitimately say: "It is false that the earth is flat."

But "this sentence" isn't a claim or part of a claim. Even "This sentence is false" isn't a claim, because falseness isn't attached to an observation any sort.

Watch me fix that...

"This sentence is four words long is false".

Now there is a claim for which the evaluation is falseness.


eudaimonia,

Mark

 

[KCfromNC]

I think it's interesting how it breaks the intuitive idea that an assertion must be true or false. Inconsistencies and paradoxes drive the evolution of science.

No. Science is driven by evidence and induction. Deductive logic problems like these are interesting but unrelated, except as so far that math is a useful language for communicating ideas in science.

But this kind of statement doesn't have anything to do with that.

 

[Eudaimonist]

"this sentence" is not a claim, "this sentence is false" refers to the whole sentence, which does make an observation about itself.

It seems to make a claim about itself, but this strikes me as a linguistic trick.

If I say that "X is false", X is the claim (if there is one), and the "is false" is an evaluation of the truth-status of the claim.

"This sentence is false" is not a claim; it is an evaluation of something's truth status. However, neither "this sentence" nor "this sentence is false" has a truth status. Neither one is a claim about anything.

Another example:

"This chair is comfortable" is false. (Includes a claim)
This chair is false. (Is just an evaluation of a truth-status, but of what? There is no claim.)


eudaimonia,

Mark

 

[Eudaimonist]

1+1=2 is false

That statement clearly has a truth value

Okay, I will grant that this may be so, but ONLY if there is a claim inside that is claimed (in this case) to be false. "1+1=2" is a claim. "This sentence" is not.

Making an assumption about the truth of "this statement is false" imbues it with a truth value

Imbues? How does it do this? It sounds like you are making this totally subjective. It's like saying "This chair is false" has a truth value because we make an "assumption" about the truth of the statement.


eudaimonia,

Mark

 

[Eudaimonist]

Once again, "this sentence" is not the claim, it is a self-reference to the claim "this sentence is false".

As I see it, there are three layers of claims. They go like this:

1) "This sentence is false" is false.
2) This sentence is false.
3) "This sentence"

(1) is saying that (2) is false. And (2) is saying that (3) is false.

So basically what I mean is that once you make an assumption about A's truth, you can determine a truth value of "A is false" based on your assumption.

Okay, understood.


eudaimonia,

Mark

 

[GrowingSmaller]

My solution is best:

I think "the sun is yelow" makes the claim: this sentence is true and this sentence also states the sun is yellow.

You know, when we say "the sun is yellow" it is assumed that we are in the assetoric mode, making an assertion or positive claim. Hence the appendage "this sentence is true" shows what is implied in ordinary language. When I say "London is in England" I mean "the sentence "London is in England" is true".

So when we examine the claim "this sentence is false" we involve ourselves in a contradiction, namely stating "this sentence is true and this sentence also states this sentence is false..." in other words we are claiming A and not-A at the same time.

If we use for an analogy the picture theory of meaning we could put it this way: "this picture is white and this picture is black". It's a dumb claim to make.

 

[GrowingSmaller]

Mark I like your solution. Were you taught it or did you read it, or is it your own creation?

 

[Nanopants]

What do you guys think?

If I were to ask you if that was an invalid syntax, would your answer be the same as your answer to this question?