Talk:Logical form

message: Now I've created the article I see the article "argument form" is similar.  My research on the history of the expression (Joyce, Wittgenstein, Russell, historically, most modern usage) suggests "logical form" is appropriate.
E.g.
:In order to understand a sentence, it is necessary to have knowledge both of the constituents and of the particular instances of the form.  It is in this way that a sentence conveys information , since it tells us that certain known objects are related according to a certain known form.  Thus some kind of knowledge of logical forms, though with most people it is not explicit, is involved in all understanding of discourse.  (Russell OKEW 53).
:'If p then p' is supposedly a "valid logical form", from which it should follow that every instance is true, indeed, is valid, is a truth of logic.  However, the alleged instance 'if John is sick then John is sick" may not be true if 'sick' is understood in one of its meanings on its first occurrence, another on the second.  Logical forms presuppose a pattern of recurrence: they assume that for each schematic letter, each token of it is to be understood as making the same contribution to logical truth and validity.  If we are to recognise a genuine instance of a logical form as valid, we must be able to recognise that replacements of equiform tokens of schematic letters make equal contributions.  Hence the concept of logical validity requires the notion of a relation between tokens which obtains only on condition that they make the same contribution to validity, and whose obtaining can be manifest to reasoners."  Sainsbury, Departing from Frege p.134.
Spinoza1111 06:22, 13 January 2006 (UTC)
thread_title:  Similar article 

message: It has been suggested that Argument form be merged into this article logical form.
The merger has been proposed a while ago already, however, as far as I can see there is substantial overlap between the two articles. Morton Shumway—talk 10:31, 20 April 2011 (UTC)
replies: text: Approve I would support that mergePhilogo (talk) 00:01, 8 February 2011 (UTC)

text: Support as it was not me who did the merger proposal. Close to identical articles, and 'argument form' in the sense of 'logical form of an argument' can easily be mentioned in the article. Morton Shumway—talk 17:06, 22 April 2011 (UTC)
thread_title: [[Argument form]]  merge into [[logical form]].

message: : Both notions are vague, but it seems that argument form necessarily uses some notion of implication.  . Or perhaps has a broader meaning, who knows. Vague philosophical stuff. . At least in basic logic texts, they are equivalent:  (Well, I see Beall treats paraconsistency in that book as well, so perhaps not so basic.) Apparently to some logical form means using a formal language, while argument form may do without . This intro logic book  also says they're the same notion, so I think we can ignore the idiosyncrasy of some philosophers and merge+redirect argument form here. Tijfo098 (talk) 19:56, 20 April 2011 (UTC)
replies: text: The terms are not equivalent.  The logical form of an argument is its argument form, but the logical form of a sentence/proposition/statement is not an argument form becuase it is not an argument.  Re argument form necessarily uses some notion of implication see  Corresponding conditional:-
In logic, the corresponding conditional of an argument (or derivation) is a material conditional whose antecedent is the conjunction of the argument's (or derivation's) premises and whose consequent is the argument's conclusion. An argument is valid if and only if its corresponding conditional is a logical truth. It follows that an argument is valid if and only if the negation of its corresponding conditional is a contradiction.  The construction of a corresponding conditional therefore provides a useful technique for determining the validity of argument
— Philogos (talk)  21:01, 21 April 2011 (UTC)
replies: text:  Is that quote from a source or are you quoting a Wikipedia article? It's also strange that you supported a merge right above, given that you see them as different. I'm fine with pointing out whatever fine distinctions some see in the joint/merged article, as long as they are sourced; there's at least one source (D. Hitchcock ) among those I found that sees such a distinction, but frankly we'd have to quote an entire paragraph from it, because it's not clear to me what it's saying in order to rephrase it. Tijfo098 (talk) 06:31, 22 April 2011 (UTC)

text:  D. Hitchcock's theory of argument form (as a broader notion than logical form) is about informal logic; see p. xvii in the intro. Hitchcock whose theory is discussed there by Pinto seems to be this guy. Tijfo098 (talk) 06:59, 22 April 2011 (UTC)
replies: text: The quote was from the Wiki article (to save you looking it up).  The terms logical form and argument form (cf argument schema) are distinct but that does not preclude merging the articles under logical form, sinc an argument form is an instance of a logical form.  (Perhaps Mr Hithccock is useing the term argument form in a unconventional way.)  This can be explained in one line in the merged argument.  I'll insert that now pre any merge, so you can see what I mean.— Philogos (talk)  12:41, 22 April 2011 (UTC)

text: It is unclear whether Tijfo098 supports or opposes the proposed merge. — Philogos (talk)  12:41, 22 April 2011 (UTC)

text: Hmm, I should have read the whole page in Beall, he does say something to that effect; I've edited the article. Tijfo098 (talk) 19:05, 22 April 2011 (UTC)
thread_title:  General discussion (moved here from merger discussion, please stick to protocol [[WP:MERGE]]) 

message: As written here it contradicts Tomassi , who sees logical form and argument form as equivalent. Like I wrote before (but apparently nobody read), Beall also defines them as synonymous. I admit it's entirely possible that someone defines it as written in this wiki article, but it requires citation, and the Tomassi-Beall-type usage should probably be mentioned as well. Tijfo098 (talk) 16:11, 22 April 2011 (UTC)
replies: text: Hmm, I should have read the whole page in Beall, he does say something to that effect; I've edited the article. Tijfo098 (talk) 19:05, 22 April 2011 (UTC)
thread_title:  Argument form def 

message: It is now necessary to edit the destination page again and delete the redundant content, editing until it looks good and consistent.— Philogos (talk)  21:29, 22 April 2011 (UTC)
replies: text: I was curious why someone created that separate article. Hurley, which was the only source cited in the argument form article defines it as "An argument form is an arrangement of statement variables and operators such that the uniform replacement of the variables by statements results in an argument." Hurley does not use the expression "logical form" at all in his book... Tijfo098 (talk) 23:06, 22 April 2011 (UTC)
replies: text: If you read the Cam Enc of Phil article it explains that an argument form includes the logical form of each premis and the conclusion and then some more: i.e it shows which are the premises and which is the conclusion.  There are various conventions for the latter, eg (a) each premiss on a new line, conclusion last on a new line preceded by a dot or the therefore sign.  (b) premises first seperated by commas then forward slash followed by conclusion.  The former step is acheived by showing the logical form of each premis and the conclusion.  Formal languages were developed specifically to express such logical forms, (hence their name) and is such a way that the grammatical form of a sentence reflects its logical form.  Thus was because with natural languages this was often not the case. (Much emphased by Frege)  However it is not NECESSARY to use a formal language to set out a logical form (merely more convenient and precise): a natural; language can be used but this is less convenient and less precise.  Formal languages are really a relativily recent development, but logicians had been discussing and setting out the logical forms of sentences for centures before their development.  (If of interest this could be set out in the history page.)  To illustrate the above take the old favourite: 
* All Greeks are Men and all men are animals therefore all Greeks are animals. 
The form of this  (i.e. its argument form) can be set out as follows.  First show which are the premises and which is the conclusion: 
* All Greeks are Men, all men are animals/all Greeks are animals
Second, show the logical form of each premis and the conclusion: 
*ALL A IS B, ALL B IS C / ALL A IS C
NB we have not used a formal language, but we have repalaced terms by place-holders. Using modern symbolism (developed post Frege - you should see HIS notation) we might write: 
*x(FxGx), x(GxHx) / x(FxHx)
— Philogos (talk)  03:08, 26 April 2011 (UTC)
thread_title:  merger 

message: Can anyone cite where Russell wrote:
"Some kind of knowledge of logical forms, though with most people it is not explicit, is involved in in all understanding of discourse. It is the business of philosophical logic to extract this knowledge from its concrete integuments, and to render it explicit and pure."— Philogos (talk)  22:05, 22 April 2011 (UTC)
replies: text: The ref cite in the article (free preprint linked, ya know) says it's from Russell, Bertrand. 1993. Our Knowledge of the External World: as a field for scientific method in philosophy. New York: Routledge. p. 53  (Of course, that's a reprint of the 1914 stuff.) Tijfo098 (talk) 22:16, 22 April 2011 (UTC)

text: Thanks— Philogos (talk)  22:33, 22 April 2011 (UTC)
thread_title:  Russell quote 

message: Although the opening sentence is based closely on the article in Camb. Enc of Phil and it was my edit, I don't like it much: I feel the following part it would not mean much to a lay reader
— Philogos (talk)  02:27, 26 April 2011 (UTC)
thread_title:  Opening sentence 

message: I am sorry to say this, but this page is very poorly written. The discussions above about Frege and Wittgenstein would be relevant if the page had more structure and sense. 
Let me note a couple of things. First the opening sentence:
"In logic the logical form of a sentence (or proposition or statement or truthbearer) or set of sentences is the form obtained by abstracting from the subject matter of its content terms or by regarding the content terms as mere placeholders or blanks on a form."
This is biased, unclear and somewhat wrong. First, what is "truthbearer"? Is Kreisel's question forgotten? Or Goedel proof? The logical form has no connection with truth per se. Second, there is no logical form of a set, and therefore not for a set of sentences. A set of sentences can be interpreted as a (larger) sentence, and then has a logical form. Third, what does "abstracting from the content mean"? This is highly biased and wrong as it assumes that there is a logical form for at most natural language sentences. How can one "abstract from the content" the sentence "int main(){}" or "\forall x\exists y P(x,y)". Those are sentences and they have a logical form. 
This is just the first sentence.
In addition, there is no mention of logical forms (!) such as prenex normal forms, Skolem normal forms, Disjunctive normal form, etc. This article is littered with bad "philosophical" logic and should be wholly rewritten.
Skansi.sandro (talk) 20:42, 14 July 2013 (UTC)
thread_title:  Bad page 

message: As a recent computer engineering graduate, I find this page too wordy. The recent introduction is too long.
* The prose doesn't have enough precision and focus on "separating syntax from logical semantics."
* No section with clear and explicit explanation of connection of the logical form to Boolean logic and other logics is sort of bad.
* Introduction of special written syntax for logical forms is not handled well enough.
There are some other style and grammar inconsistencies. I will try and fix them in the coming week. --Atasato (talk) 11:13, 8 June 2018 (UTC)
replies: text: The article also doesn't explain how ambiguous statements are formalized. Wouldn't the logical form of an ambiguous statement be the logical disjunction of all of its possible meanings? Jarble (talk) 01:57, 19 February 2024 (UTC)
thread_title:  Probably needs significant revision