jsfisher
ETcorngods survivor
- Joined
- Dec 23, 2005
- Messages
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Please direct me to the point I were (mis-)responding to.
You are having that much trouble figuring out what part of my post you responded to?
Please direct me to the point I were (mis-)responding to.
I agree with you that I wrongly assumed that your professional level of mathematics enables you to understand that {a,b,c,...} or {{},{a,b,c,...},...} are expressions that are used "without loss of generality".
You wrote that I were (mis-)responding to something, so please direct me to the part of your post that were (mis-)responded by me.You are having that much trouble figuring out what part of my post you responded to?
The claim that philosophy has no impact on the math, is simply your philosophical point of view, so?Whether you accept or agree with Cantor on a philosophic basis has no impact on the math.
You wrote that I were (mis-)responding to something, so please direct me to the part of your post that were (mis-)responded by me.
The claim that philosophy has no impact on the math, is simply your philosophical point of view, so?
{a,b,c,...} or {{},{a,b,c,...},...} are easily understood as A and P(A) expressions without a loss of generality, unless one insists to deal with notations instead of notions, and probably this is your case.That's the thing about Mathematics.
Not at all. It is the one involving P(A) members that is not paired with any A member, such that both P(A) and A members are inaccessible to the platonic common objective (discovered) level of actual infinity (notated the outer "{" and "}" in both sets).If it is the one involving the cardinality of a set and its power set, then there is a whole preface you need to provide about cardinality. Yet another thing you omitted.
It is the one involving P(A) members that is not paired with any A member, such that both P(A) and A members are inaccessible to the platonic common objective (discovered) level of actual infinity (notated the outer "{" and "}" in both sets).
{a,b,c,...} or {{},{a,b,c,...},...} are easily understood as A and P(A) expressions without a loss of generality, unless one insists to deal with notations instead of notions, and probably this is your case.
That there is no bijection between P(A) and A members, which is a relative measure that is inaccessible to the absolute level of the platonic common existence of both sets (which is notated by the outer "{" and "}" of {a,b,c,...} or {{},{a,b,c,...},...} that are easily understood as A and P(A) expressions without a loss of generality).Edited by full replacement:
So, what is the statement of Cantor's Theorem you had in mind?
jsfisher said:... defining cardinality of sets in terms of numbers isn't appropriate. Instead, we can define it as a relative measure, the comparison of the cardinality of two sets, and thereby avoid the use of numbers (until later).
"There exists set X" is only a tautology, where what comes after "such that" is not only a tautology (and in the case of Cantor's Theorem, J's "existence" involved with contradiction, where this contradiction has no impacted on the platonic common level of existence of both P(A) and A, because this common level of existence is only a tautology).
That there is no bijection between P(A) and A members, which is a relative measure that is inaccessible to the absolute level of the platonic common existence of both sets (which is notated by the outer "{" and "}" of {a,b,c,...} or {{},{a,b,c,...},...} that are easily understood as A and P(A) expressions without a loss of generality).
As long as one does not understand that platonic existence is a discovery that does no need any meaning in order to exist (it is a tautology of existence that does not need any further interpretation or meaning), one wrongly gets this discovery only in terms of subjective invented multiple interpretations and meanings that are not the discovered tautology of existence.
No jsfisher, once again you get discovery in terms of invention.Excellent. You finally admit your invented terminology has no meaning. On this we can all agree.
The claim that philosophy has no impact on the math, is simply your philosophical point of view, so?
It is gibberish from your one level reasoning of set, which does not distinguish between the discovered level of A and P(A) (notated by the outer "{" and "}") and the invented level of A and P(A) (notated by their members, and the mapping (which is not bijective, in this case) is done at the invented level of members of these sets).By the way, Doron, do you realize that a bijection between A and P(A) isn't the same as between the members of A and P(A)? The latter is gibberish.
1. Axioms in the framework of mathematics do not need any proof, otherwise they are not axioms, in the first place.You are the one that is claiming philosophy has an impact on math. Too bad you haven't provided any proof of that. Lots of claims, no proof.
As long as one does not understand that platonic existence is a discovery that does no need any meaning in order to exist (it is a tautology of existence that does not need any further interpretation or meaning), one wrongly gets this discovery only in terms of subjective invented multiple interpretations and meanings that are not the discovered tautology of existence.
No jsfisher, once again you get discovery in terms of invention.
2. By using philosophical view of these axioms, I explicitly demonstrated that they are derived from using platonic and non-platonic levels, where the existence at the platonic level is only tautology.
Let's take. for example the Axiom Of Infinity:
"There exists a set X (the discovered level of set X) such that (the invented level of set X) the empty set is a member of X and, whenever a set y is a member of X, then Sis also a member of X".
Please look again at the end of http://www.internationalskeptics.com/forums/showpost.php?p=10024836&postcount=3762.Citation needed. Please show exactly where you got the full quote.
"Invention of the discovered" does not make sense.
"Discovery of the invented" makes sense.
By using Cantor's theorem it is shown in example 1 of http://www.internationalskeptics.com/forums/showpost.php?p=10030370&postcount=3795 that set {} exists even if according to its definition (as used by Cantor's theorem) any attempt to define some A member as its member, is involved with contradiction (at the level of members of that set).
No it has not been shown. It has been claimed.
There is a fundamental difference between the two.
Citation needed. Please show exactly where you got the full quote.
Please look again at the end of http://www.internationalskeptics.com/forums/showpost.php?p=10024836&postcount=3762.
Let's take. for example the Axiom Of Infinity:
"There exists a set X (the discovered level of set X) such that (the invented level of set X) the empty set is a member of X and, whenever a set y is a member of X, then Sis also a member of X".
For example, nothing was stripped or "slightly hacked" from ZFC by post http://www.internationalskeptics.com/forums/showpost.php?p=10017698&postcount=3731, only in your one level imagination.
My mistake (I used what is written in http://en.wikipedia.org/wiki/Zermelo–Fraenkel_set_theory without first checking it) the correct one is "the empty set ({})". Thank you for your remark.
"There exists a set X (the discovered level of set X) such that (the invented level of set X) the empty set is a member of X and, whenever a set y is a member of X, then Sis also a member of X".
This time please read what is written in http://en.wikipedia.org/wiki/Zermelo–Fraenkel_set_theory about the axiom of infinity.So once again doronshadmi, give me the citation which shows:
I explain Cantor's theorem by using an example without loss of generality (http://en.wikipedia.org/wiki/Without_loss_of_generality), where this kind of explanation is supported by http://en.wikipedia.org/wiki/Cantor...ion_of_the_proof_when_X_is_countably_infinite.It is worse than that. He's not even using Cantor's Theorem, and even if Cantor's Theorem were anything like what he imagines Cantor's Theorem to be, he still wouldn't be using Cantor's Theorem.
Cantor's Theorem, always available for anyone to use, is simply |S| < |P(S)| for any set S.
Doron is not using that (or anything like it) at all. Instead, he's convinced the theorem is actually its standard proof method, and it is the proof method he is misconstruing and misapplying (and then fantasizing about addition stuff he'd really like included).
It is fun to watch, though.
{ a , b , c , ... }
↕ ↕ ↕
{{a},{b},{c}, ... }
It is worse than that. He's not even using Cantor's Theorem, and even if Cantor's Theorem were anything like what he imagines Cantor's Theorem to be, he still wouldn't be using Cantor's Theorem.
Cantor's Theorem, always available for anyone to use, is simply |S| < |P(S)| for any set S.
Doron is not using that (or anything like it) at all. Instead, he's convinced the theorem is actually its standard proof method, and it is the proof method he is misconstruing and misapplying (and then fantasizing about addition stuff he'd really like included).
It is fun to watch, though.
Jsfisher, it is realized that your "Cantor's Theorem, always available for anyone to use, is simply |S| < |P(S)| for any set S" statement is not supported by your understanding that Cantor's Theorem rigorously can be explained by using examples without loss of generality.
This time please read what is written in http://en.wikipedia.org/wiki/Zermelo–Fraenkel_set_theory about the axiom of infinity.
The above quoted from wikipedia...7. Axiom of infinity[edit]
Main article: Axiom of infinity
Let S(w)\! abbreviate w \cup \{w\} \!, where w \! is some set (We can see that \{w\} is a valid set by applying the Axiom of Pairing with x=y=w \! so that the set z\! is \{w\} \!). Then there exists a set X such that the empty set \varnothing is a member of X and, whenever a set y is a member of X, then S\! is also a member of X.
\exist X \left [\varnothing \in X \and \forall y (y \in X \Rightarrow S\in X)\right ].
More colloquially, there exists a set X having infinitely many members. The minimal set X satisfying the axiom of infinity is the von Neumann ordinal ω, which can also be thought of as the set of natural numbers \mathbb{N}.
This is nothing but your philosophical view, which does not agree with, for example, Poincaré's philosophical view (as appears at the end of http://en.wikipedia.org/wiki/Set-theoretic_definition_of_natural_numbers#Problem):However, since arithmetic is built on set theory and not the other way around, defining cardinality of sets in terms of numbers isn't appropriate. Instead, we can define it as a relative measure, the comparison of the cardinality of two sets, and thereby avoid the use of numbers (until later).
These problems with defining number disappear if one takes, as Poincaré did, the concept of number as basic i.e. preliminary to and implicit in any logical thought whatsoever. Note that from such a viewpoint, set theory does not precede number theory.
This is nothing but your philosophical view, which does not agree with, for example, Poincaré's philosophical view (as appears at the end of http://en.wikipedia.org/wiki/Set-theoretic_definition_of_natural_numbers#Problem)
I explain Cantor's theorem by using an example....
You go to such amazing lengths to make things seem far more complicated than they are. Cantor's Theorem is not at all hard to explain. For any set S, |S| < |P(S)|. See? Easy.