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Archive 1 |
I will revert such additions as [1] until the source where the rule of inference is called "material conditional" (not versa) will be demonstrated. Incnis Mrsi ( talk) 07:03, 24 February 2012 (UTC)
Okay, so there are many instances where concepts under "arguments," "theorems" and "rules of inference" have more than one article, and some where there is only one. There is this particular rule of inference here we are having a problem with right now. I wonder how you intend to address the larger issue? Is there some other name for this that you prefer? If we decide to merge many of these instances where more than one can be merged into one, it would be nice to make sure to provide for the rules of inference. If we make separate articles for each, it would be nice to provide a connection to the other articles expressing the same concept. In the case of material implication, I have to stand by the Hurley use "valid rule of inference that allows a horseshoe to be replaced by a wedge if and only if the antecedent is negated" He abbreviates it Impl as does Moore/Parker. I don't understand why anyone is ignoring that. However, what I would like to know is if you have a different name, or just are against this as a concept or what. Greg Bard ( talk) 11:41, 27 February 2012 (UTC)
Someone explain to me how Hurley is not a reliable source. It's in it's tenth edition at least. Also explain the reliable source which uses each of your proposals. Listen, I don't really feel strongly about it. Just figure out a name, and have a real good reason for moving it, and I'll go along. So far, tenaciously ignoring sources presented is not a good way to be. I would like to stay consistent with this transformation rules template. I would be open to moving it to material implication (rule of inference) if that avoids the issue somehow. But then why would that change anything? Greg Bard ( talk) 20:27, 27 February 2012 (UTC)
Please note that, since the cited article says that material implication is a CONNECTIVE, the disputed tag should remain until resolved. I have not been able to access the cited book, but most books say the same thing (indeed, the phrase "material implication is a rule" gets zero hits). I believe the article author has misunderstood what they have read. It is of course a fact that is equivalent to , but this fact is stated at material conditional. I recommend redirecting this article to that target. -- 202.124.73.250 ( talk) 22:10, 24 February 2012 (UTC)
I note also that a book search for "material conditional or material implication" finds several books stating that the phrases both refer to the same connective, i.e. material conditional. -- 202.124.73.250 ( talk) 22:18, 24 February 2012 (UTC)
The material implication is not just any of the symbols or .
This article and the related one material conditional pay too much attention in the meaning of the implication connective. That should be part of the article about logic. The problem that makes important the material adjective comes from examples like this:
although the antecedent speaks about a different thing than consequent, it is a true statement because according to the true table for implication: false => true is true, moreover, one can conclude anything from a false antecedent, for that reason a set of premises should be consistent, false should not be obtained from them, otherwise any conclusion can be derived.
That is, the adjective material, is needed when one refers to implication with its meaning as the implication true table, to distinguish it from the deeper problem that gave rise to modal logics, barely speaking, the need to represent more accurately the relation between premises and conclusions.
The cited bibliography is introductory and do not address this problem in depth. This subject is better addressed in more philosophical books in modal logics, and the handbook of modal logic. This article seems written by enthusiastic, but confused, students, that have not that knowledge yet. Please refrain to write about subjects that you don't have a deep knowledge, an introductory course is not enough. This seems a growing problem in wikipedia, lowering it's quality and introducing many absurd disputes. As a computer scientist I could write this article, but I refrain from that because, doing that before in other articles where I can write something correct, was just a waste of my time, when the "owners of the page" fanatically erased my contributions. I do not know if this is the case with this article, but here some more observations:
Who wrote this article does not have clear several things. The symbol <=> is not a metasymbol, p <=> q is an abbreviation of (p => q) & (q => p). (s)he does not have clear what is understood by an axiomatic system. In the axiom (p => q) <=> (~p | q), the symbol <=> may be read as "is equivalent to", there is a relation between the implication =>, and the syntactic turnstile — Preceding unsigned comment added by 201.103.56.195 ( talk) 20:31, 14 June 2012 (UTC)
This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 |
I will revert such additions as [1] until the source where the rule of inference is called "material conditional" (not versa) will be demonstrated. Incnis Mrsi ( talk) 07:03, 24 February 2012 (UTC)
Okay, so there are many instances where concepts under "arguments," "theorems" and "rules of inference" have more than one article, and some where there is only one. There is this particular rule of inference here we are having a problem with right now. I wonder how you intend to address the larger issue? Is there some other name for this that you prefer? If we decide to merge many of these instances where more than one can be merged into one, it would be nice to make sure to provide for the rules of inference. If we make separate articles for each, it would be nice to provide a connection to the other articles expressing the same concept. In the case of material implication, I have to stand by the Hurley use "valid rule of inference that allows a horseshoe to be replaced by a wedge if and only if the antecedent is negated" He abbreviates it Impl as does Moore/Parker. I don't understand why anyone is ignoring that. However, what I would like to know is if you have a different name, or just are against this as a concept or what. Greg Bard ( talk) 11:41, 27 February 2012 (UTC)
Someone explain to me how Hurley is not a reliable source. It's in it's tenth edition at least. Also explain the reliable source which uses each of your proposals. Listen, I don't really feel strongly about it. Just figure out a name, and have a real good reason for moving it, and I'll go along. So far, tenaciously ignoring sources presented is not a good way to be. I would like to stay consistent with this transformation rules template. I would be open to moving it to material implication (rule of inference) if that avoids the issue somehow. But then why would that change anything? Greg Bard ( talk) 20:27, 27 February 2012 (UTC)
Please note that, since the cited article says that material implication is a CONNECTIVE, the disputed tag should remain until resolved. I have not been able to access the cited book, but most books say the same thing (indeed, the phrase "material implication is a rule" gets zero hits). I believe the article author has misunderstood what they have read. It is of course a fact that is equivalent to , but this fact is stated at material conditional. I recommend redirecting this article to that target. -- 202.124.73.250 ( talk) 22:10, 24 February 2012 (UTC)
I note also that a book search for "material conditional or material implication" finds several books stating that the phrases both refer to the same connective, i.e. material conditional. -- 202.124.73.250 ( talk) 22:18, 24 February 2012 (UTC)
The material implication is not just any of the symbols or .
This article and the related one material conditional pay too much attention in the meaning of the implication connective. That should be part of the article about logic. The problem that makes important the material adjective comes from examples like this:
although the antecedent speaks about a different thing than consequent, it is a true statement because according to the true table for implication: false => true is true, moreover, one can conclude anything from a false antecedent, for that reason a set of premises should be consistent, false should not be obtained from them, otherwise any conclusion can be derived.
That is, the adjective material, is needed when one refers to implication with its meaning as the implication true table, to distinguish it from the deeper problem that gave rise to modal logics, barely speaking, the need to represent more accurately the relation between premises and conclusions.
The cited bibliography is introductory and do not address this problem in depth. This subject is better addressed in more philosophical books in modal logics, and the handbook of modal logic. This article seems written by enthusiastic, but confused, students, that have not that knowledge yet. Please refrain to write about subjects that you don't have a deep knowledge, an introductory course is not enough. This seems a growing problem in wikipedia, lowering it's quality and introducing many absurd disputes. As a computer scientist I could write this article, but I refrain from that because, doing that before in other articles where I can write something correct, was just a waste of my time, when the "owners of the page" fanatically erased my contributions. I do not know if this is the case with this article, but here some more observations:
Who wrote this article does not have clear several things. The symbol <=> is not a metasymbol, p <=> q is an abbreviation of (p => q) & (q => p). (s)he does not have clear what is understood by an axiomatic system. In the axiom (p => q) <=> (~p | q), the symbol <=> may be read as "is equivalent to", there is a relation between the implication =>, and the syntactic turnstile — Preceding unsigned comment added by 201.103.56.195 ( talk) 20:31, 14 June 2012 (UTC)