raydpratt
08-16-07, 05:41 PM
I'm hoping for some feedback on the following arguments, largely inductive, about the Liar's Paradox from anyone well versed such arguments. If the argument fails, I would like to know exactly where.
The Liar's Paradox arises from statements like "This very statement is a false proposition." As the argument pointing out the paradox goes, if such a statement is taken as true, then it must be false as it claims; but, if it is false as it claims, then it has made a truthful statement about its falsity and must be taken as true, and thus the argument begins anew, ad infinitum.
Normally, as a matter of logic, a statement declared to be true or false is a statement that was compared to some referent fact or concept and either found to match or not to match.
Thus, when we say that a statement is true or false, we imply or show that such a comparative process can be and has been carried out.
With the correct process in mind for how to comparatively find a statement to be true or false, let us look closer at the exact meaning of a statement that gives rise to the Liar's Paradox:
"This very statement is a false proposition."
The subject-class of this proposition is the whole statement itself, and the proposition ascribes to its subject-class the predicate-class quality of being a statement that can be proven false by comparison to a referent fact or concept.
In judging the truth value of the statement, we need only compare the attributes of the subject class -- here the statement itself -- with the attributes of the predicate class -- here the comparative process of how we find statements to be true or false (inductively).
The subject class of the statement declares itself to be false, ipse dexit, but this is at variance with the predicate class which requires that statements be proven true or false by comparison to a referent fact or concept.
So, the statement has made a provably false proposition, and thus it correctly states that it makes a false proposition, and thus its final outside truth value is true.
Conversely, to clarify the point, the opposite statement that "This very statement is a true proposition," would have a final outside truth value of false because the statement asserts itself to be true rather than being found true. The subject class -- the statement itself -- falsely ascribes to itself the predicate-class quality of being found true by comparison to a referent fact or concept.
Someone will urge, of course, that we have not dispensed with the Liar's Paradox because we must change our final outside truth value because it is contradicted by the self-assigned truth value of the statement itself -- whether it be the positive version or the negative version of the statement (the negative version gets the most press).
We should counter, of course, that the self-assigned truth values of either the positive or negative versions of the statement were a part of the very matter that we judged with a correct, comparative process for determining the truth or falsity of propositions. Thus, we may reject as unsound the argument that we must change our final outside truth values based solely on the contradictory truth values alleged in the statements themselves.
Specifically, with the little-discussed positive version of the statement above (a.k.a. "The Truth Teller"), we have simply and correctly disagreed that it states a true proposition.
Likewise, with the negative version of the statement, we have come to correctly understand the statement and have agreed with its assertion that it makes a false proposition -- thus, there is either no contradiction in giving the statement a final outside truth value of true or, at the very least, we have correctly disagreed with the statement's self-asserted final outside truth value of being false.
In short, we prefer a sound process for determining the truth or falsity of propositions, not an unsound rule that changes our final judgments with a simple decree of disagreement.
This should be the logical death of the Liar's Paradox, and a very welcome death for those of us who value logic as a practical matter.
Many of us have been doubtlessly tortured by the endless sing-song chants of "if true, then false, and if false, then true," etc., printed endlessly onto the paper remains of ever more dead trees.
Let's work together to spread and even sharpen the logical necessity of the long-awaited demise of the Liar's Paradox.
Very Respectfully,
Ray Donald Pratt
The Liar's Paradox arises from statements like "This very statement is a false proposition." As the argument pointing out the paradox goes, if such a statement is taken as true, then it must be false as it claims; but, if it is false as it claims, then it has made a truthful statement about its falsity and must be taken as true, and thus the argument begins anew, ad infinitum.
Normally, as a matter of logic, a statement declared to be true or false is a statement that was compared to some referent fact or concept and either found to match or not to match.
Thus, when we say that a statement is true or false, we imply or show that such a comparative process can be and has been carried out.
With the correct process in mind for how to comparatively find a statement to be true or false, let us look closer at the exact meaning of a statement that gives rise to the Liar's Paradox:
"This very statement is a false proposition."
The subject-class of this proposition is the whole statement itself, and the proposition ascribes to its subject-class the predicate-class quality of being a statement that can be proven false by comparison to a referent fact or concept.
In judging the truth value of the statement, we need only compare the attributes of the subject class -- here the statement itself -- with the attributes of the predicate class -- here the comparative process of how we find statements to be true or false (inductively).
The subject class of the statement declares itself to be false, ipse dexit, but this is at variance with the predicate class which requires that statements be proven true or false by comparison to a referent fact or concept.
So, the statement has made a provably false proposition, and thus it correctly states that it makes a false proposition, and thus its final outside truth value is true.
Conversely, to clarify the point, the opposite statement that "This very statement is a true proposition," would have a final outside truth value of false because the statement asserts itself to be true rather than being found true. The subject class -- the statement itself -- falsely ascribes to itself the predicate-class quality of being found true by comparison to a referent fact or concept.
Someone will urge, of course, that we have not dispensed with the Liar's Paradox because we must change our final outside truth value because it is contradicted by the self-assigned truth value of the statement itself -- whether it be the positive version or the negative version of the statement (the negative version gets the most press).
We should counter, of course, that the self-assigned truth values of either the positive or negative versions of the statement were a part of the very matter that we judged with a correct, comparative process for determining the truth or falsity of propositions. Thus, we may reject as unsound the argument that we must change our final outside truth values based solely on the contradictory truth values alleged in the statements themselves.
Specifically, with the little-discussed positive version of the statement above (a.k.a. "The Truth Teller"), we have simply and correctly disagreed that it states a true proposition.
Likewise, with the negative version of the statement, we have come to correctly understand the statement and have agreed with its assertion that it makes a false proposition -- thus, there is either no contradiction in giving the statement a final outside truth value of true or, at the very least, we have correctly disagreed with the statement's self-asserted final outside truth value of being false.
In short, we prefer a sound process for determining the truth or falsity of propositions, not an unsound rule that changes our final judgments with a simple decree of disagreement.
This should be the logical death of the Liar's Paradox, and a very welcome death for those of us who value logic as a practical matter.
Many of us have been doubtlessly tortured by the endless sing-song chants of "if true, then false, and if false, then true," etc., printed endlessly onto the paper remains of ever more dead trees.
Let's work together to spread and even sharpen the logical necessity of the long-awaited demise of the Liar's Paradox.
Very Respectfully,
Ray Donald Pratt