Talk:Syllogism

There, cleaned it up a bit and wrote the stuff about majors and minors. Removed cleanup tag, but it still needs tender loving attention from a father-figure logician, the poor thing. I just don't know enough about the subject. saturnight 22:53, Sep 3, 2004 (UTC)

Note that Term logic and Talk:Term logic contain even more about syllogisms than this article does. Things need to be moved from there to here. I'd do it if I knew anything about syllogisms (which I don't at present). — mark ✎ 15:07, 2 Mar 2005 (UTC)

Looking for Something about Square of opposition

This is a relatively important logical construct, and needs to be added as a link, along with the logical relationships of contraries, subalterns, subcontraries, and contradictions. I recently took a course in logic that was heavy into syllogism, and we used the square of opposition a lot. Thought or feelings? Is there a place within the article that would best describe and illucidate this concept, or am I really best just to put a link in the "see also" section? Thanks. Asday85 (talk) 17:07, 30 January 2008 (UTC)

Question

Any relationship to "JISM"? —Preceding unsigned comment added by 68.96.213.27 (talk) 23:42, 1 October 2007 (UTC)

Not that I know of... can you be more clear? 129.93.16.77 (talk) 21:04, 14 January 2008 (UTC)

A Philosopher Professor

Come on. Is there seriously no professor in logic who has taken to editing this article? Get with the program, academia. "...deductive reasoning, where facts are determined by combining existing statements, in contrast to inductive reasoning where facts are determined by repeated observations." Who on earth wrote that? existing statements? Denito 16:26, 25 August 2007 (UTC)

men (will) die

This piece is, pedantically speaking, wrong.

Men die. (general principle)

Socrates is a man. (specific statement)

Socrates will die. (application of major to minor)

The correct conclusion would be "Socrates dies." The problem is that semantics and syntax are funnily linked, such that for semactic equivalence "will" has to be included in the conclusion. Solutions I can think of:

• men die -> men will die; probably wrong though
• Socrates will die -> Socrates dies; probably equally wrong semantically as the previous option
• die -> die some day
• die -> have finite lifespan
• men die -> Every human will die; Good and also makes the implied "every" which is needed for this to be valid reasoning, explicit.

Comments? --MarSch 12:38, 2 September 2005 (UTC)

Actually the next sentence in the article hints that the major used to be "All men are mortal", which is probably even better. I will reinstate this. --MarSch 12:41, 2 September 2005 (UTC)

I added a bit about this, too, to explore the relationship of time in syllogisms  :-) Ted 18:41, 17 January 2006 (UTC)

Made some additions

I added a good bit to the syllogisms page. I thought it would be nice to have something more accessible than formal logic normally gets. Comments and revisions are (of course) welcome. Twrigley 18:58, 15 January 2006 (UTC)

WHY is it called the Barbara Syllogism?

I just searched the net, and found not a single explanation of why it's called the Barbara Syllogism.

Anyone here know? That definitely should be included in the article.Kaz 16:52, 19 January 2006 (UTC)

According to Bertrand Russell, it is an acronym from Greek. That ought to help you in your search. The book was in my high school library, so now you have an even short search list, meaning that it couldn't have been a very esoteric title by Russell, but one of his popularizations. --Ancheta Wis 17:56, 19 January 2006 (UTC)

It's part of a medieval mnemonic. Each syllogism involves three propositions labelled "A", "E", "I" or "O", and so each syllogism is given a word that contains those three letters in order. Hence the syllogism deriving an All conclusion from two All premises needs a word with three As as its first three vowels: Barbara was chosen, but it could have been calamari. --- Charles Stewart^(talk) 18:00, 19 January 2006 (UTC)

So that explains why celarent was another of those mnemonics. --Ancheta Wis 18:13, 19 January 2006 (UTC)

In fact the whole mnemonic is given and explained at Term logic#Conversion and reduction. Should this page should be merged there? --- Charles Stewart^(talk) 19:04, 19 January 2006 (UTC)

I'm not certain about merging - I'm still trying to get a handle on the over-all structure of wikipedia, while Wittgenstein laughs at me from the back of my head (hierarchical knowledge structures; please!!!). for a pro-tem solution, though, I'll add your explanatory link.  :-) Ted 18:54, 20 January 2006 (UTC)

I came here looking for an explanation of the consonants in the mnemonic words for syllogisms, and apparently that text no longer exists on this page or Term logic. I was able to get some information from historical versions of Term logic but it seems like it should be on an active page. Gimmetrow 20:54, 15 May 2006 (UTC)

---

well, I went and looked through the Term logic page, and there is a lot of overlap. certainly the sections on syllogisms parallel what is given here. it seems our choices (aside form leaving things exactly as they are - lol) are these:

1. bring the sections on syllogisms from term logic and integrate them here, leaving a link
2. create a single combined page under the heading term logic
3. create a single combined page under the heading syllogisms

personally, I think 'syllogism' is the more common term, but what do I know? at any rate, we'd need to link the unused term back to the new term; does anyone know how to do that? Ted 19:58, 20 January 2006 (UTC)

---

There's an answer to this. The medieval mnemonic (attributed to Peter of Spain, is hardly a secret. It encodes, not just which pairs of premises in each figure give a conclusion and what that conclusion is, but also how Aristotle proves the validity of that syllogism in Prior Analytics I.4-6. Names are constructed like this:

1. The vowels "a","e","i", and "o" are used for the four types of categorical sentence:
   • "a" = universal affirmati
   • "e" = universal negative
   • "i" = particular affirmative
   • "o" = "particular negative"
Allegedly, the vowels are chosen because "a" and "i" (for the affirmative types) are the first two vowels in "affirmo" ("I affirm") and "e" and "o" the vowels in "nego" ("I deny").
2. The names for the four first-figure forms begin with the first four consonants of the alphabet: B, C, D, F
3. Consonants then get added for euphony (but note that "r" and "l" dominate and that there's no "s", "m", "c", "p"): Barbara, Celarent, Darii, Ferio
4. The four first-figure forms are "perfect" and need no proof
5. For the second and third figure moods (Aristotle does not recognize a fourth figure), the name is an encoding of Aristotle's method of proof. His proofs consist of what he calls "reduction" to a first-figure form, which is a matter of (1) replacing premises by other sentences they imply until a pair of first-figure premises is reached, (2) drawing the conclusion of that pair, (3) if needed, drawing a further consequence of that conclusion to get a form that fits the original figure. For these replacements, Aristotle only uses "conversion", which is interchanging subject and predicate of a sentence. An "e" or "i" sentence implies its converse, and an "a" sentence implies the sentence you get by converting it and changing to an "i". The mnenomic calls the first of these "simple conversion" (conversio simplex, abbreviated by "s" after the premise's letter) and the second "conversion per accidens" (conversio per accidens, abbreviated by "p" after the premise's letter). Sometimes, major and minor premise must be swapped to get to the first figure; "m" is used to abbreviate this. We then get mnemonics like these:
   • Camestres (2nd fig.): (1) convert the "e" premise (Camestres); (2) swap major and minor premises (Camestres); (3) this gives you Celarent in the first figure (Celarent), with an "e" conclusion; (4) convert the conclusion (Camestres) to get the second-figure conclusion you need
   • Felapton (3rd fig.): (1) convert the "a" premise (Felapton); (2) this gives you Ferio in the first figure (Felapton), with an "o" conclusion/li>

   In some cases, it's impossible to get a proof using the conversion methods (second-figure Baroco, third-figure Bocardo). So, Aristotle uses indirect proof (assume the contrary of the desired conclusion, which with one of the premises will give you a first-figure form; the conclusion of this is the contradictory of the other premise; infer the desired conclusion by reductio ad absurdum). The mnemonics mark such cases with a "c" (for per contradictionem) after the premise that's contradicted. So:

   • Baroco 2nd. figure): Given premises "all Bs are As" and "some Cs are not As", assume "All Cs are Bs"; with the first premise, this gives (via Barbara) "All Cs are As, which contradicts the second premise; therefore, infer the denial of the assumption "All Cs are Bs" to get "Some Cs are not Bs".

   That at any rate is a brief account of the mnemonics. Aristotle of course knew nothing about them.

For a more detailed discussion of the significance of these names, see Paul Spade, <a href="http://pvspade.com/Logic/docs/thoughts1_1a.pdf">Thoughts, Words, and Things: An Introduction to Medieval Logic and Semantic Theory</a>, pp. 21-25.

--Robin Smith (Actually, my translation of the Prior Analytics is cited in the bibliography for this page) 128.194.75.5 (talk) 14:32, 25 August 2008 (UTC)

Major Change

I've integrated the Term Logic and Syllogism pages, and redirected the former to the latter. I've still got itchy little stuff to do (formatting and highlighting, and checking related pages to restructure things) but I think this works. let me know if you disagree. Ted 04:24, 5 February 2006 (UTC)

I'm uncomfortable with the change. There's more to term logic that the syllogism, even if syllogistic inference is the center of term logic. For example, there are two forms of inference in Aristotelian logic that are non syllogisms: axioms such as "A is A", and those that are recorded in the square of oppositions, such that the inference of contradiction from All As are B and Some As are not B.

Let's not hurry about reversing the change: I like the gathering together of all the scraps of content into one article. We should figure out what differences we mean between:

1. Term logic

2. Aristotelian logic, and

3. Syllogistic logic

--- Charles Stewart^(talk) 18:36, 5 February 2006 (UTC)

ok. I'll confess it wasn't clear to me exactly what 'term logic' referred to. sometimes it seemed to be an alternate phrase for syllogisms, sometimes to be a broader term for aristotelian logic (but only to the parts that dealt with syllogisms, since it never seems to apply to propositional logic). perhaps I was a bit over-aggressive in my integration.  :-) tentative breakdown, along your lines:

• Aristotelian Logic: everything discussed in the Prior Analytics and On Interpretation (to distinguish it from Organon proper)
• Term Logic: the system of logical deduction dealing with internal categorical structures that developed (over a millennium or two) from Aristotelian Logic.
• Syllogisms: the particular symbolic form that Term Logic takes.

By this breakdown, section 1 would clearly go on a term logic page, sections 3 and 4 on a syllogism page. section 2 is less clear: parts go one way, parts go another, and some are just stuck in the middle, spinning. comments or ideas? Ted 22:05, 5 February 2006 (UTC)

Excessive subtext

• JA: Could active editors put all but routine editorial comments and communications on the discussion page instead of enscouncing sotto voce asides in the article, as the latter are really hard to follow what's going on for interested bystanders watching the diff and hist displays. Gratia in futuro, Jon Awbrey 18:28, 5 February 2006 (UTC)

sure thing, sorry. Ted 22:03, 5 February 2006 (UTC)

oh dear

Oh no! I wrote the original article "Term Logic". I've just noticed the change that incorporates Term Logic into "Syllogism". This was not the right thing to do. Broadly:

• "Term logic" signifies the crucial feature of Aristotelian logic that analyses propositions into two terms, with the logical constants "all" "some" &c. Thus "All/some/no A's are / aren't B's". • "Aristotelian logic" signifies the logic developed by Aristotle in the books collectively known as the Organon. This happens to be a form of term logic. • "Syllogistic" refers to the form of inference that is connected with term logic. It is a much narrower concept, in fact is a part of term logic.

Thus Term logic = semantics of terms + theory of the proposition + syllogistic

Aristotelian logic = a version of term logic ( the only version as it happens, but the two should not be confused. An alien civilisation might develop a form of term logic, but it wouldn't properly be 'Aristotelian' logic).

I will have to change all this back in a way that is logical. Dbuckner 11:20, 6 March 2006 (UTC)

yes, this is acceptable. Charles made a similar comment some time back, and I see the point. the only difficulty I've had (which is why I haven't effected such a change myself - still pondering) is that there's a certain overlap in the content that's difficult to parse. as far as I can see it, the original distinction between propositional logic and syllogistic logic was Aristotle's: he split the analysis of the relationship between propositions from the analysis of the internal structure of a singular proposition. term logic developed as an elaboration and refinement of syllogistic logic, which (despite it's sophisitication) never seems to step beyond the bounds of Aristotle's original construct. in terms of structure, your equation holds; in terms of historical development, term logic is derivative of syllogisms; in pragmatic terms there are certain things (like mood and figure) that it would seem need to be discussed on both articles, thus creating a good bit of redundancy.

options:

• rewrite and restructure to make the distinction clearer, but keep the content on one page

this may involve renaming the page Term Logic and redirecting syllogisms there

• split the page into two, dividing content appropriately

how then to divide some of the mutually relevent content? Ted 14:47, 6 March 2006 (UTC)

Personal essay

I've reverted to an earlier version because this seems to have turned into a personal essay, which is not to say that nothing good had been added (some of it is worth keeping, for sure), but the tone is unencyclopedic in places e.g. "Note, however, that the decline was a protracted affair. It is simply not true that there was a brief "Frege Russell" period 1890-1910 in which the old logic vanished overnight." These phrases "Note, however ..." and "It is simply not true ..." are POV. We report what reputable publications have written and no more, and the material has to be sourced. See WP:NOR, WP:V, and WP:RS. SlimVirgin ^(talk) 19:08, 6 March 2006 (UTC)

Twrigley, I have no problem with some of the good material being restored, but it needs to be built up slowly and sourced properly. As it stands, it looks like someone's personal essay. SlimVirgin ^(talk) 19:26, 6 March 2006 (UTC)

Slim, thanks, but please consider two things:

1. the other editors and I are about to restructure the page again, to separate term logic from syllogisms; this should eliminate your 'personal essay' concerns. (you should also know that the part you are marking as a personal essay wasn't my work, but that of another editor that I worked into this article at his request)
2. the current version is a substantial improvement over the earlier; I believe the other editors would agree that editing is preferred to reversion at this point.

I was expecting your visit, though it makes me sad. please feel free to edit without destroying the structure of the page. Ted 19:29, 6 March 2006 (UTC)

Charles, Dbuckner: SlimVirgin is pissed at me because I gave her a hard time on a different page. this is payback, I suppose... I'm going to go report her for vandalism right now; please, if one of you would revert the page to it's established form? I see know reason why you or the page should suffer because of her bad temper.

Thanks Ted 19:33, 6 March 2006 (UTC)

I saw some of your work here, for example, [1] which is why I'm concerned. We can't include edits such as "Formal logic is a complex game. And I do mean game ..."

As for this being "payback," please AGF. I'm not here because I'm "pissed" at you, but because I'm not convinced you're familiar with our content policies, and so I've looked at your edits. As I said, I have no trouble with some of the good material being added back, but you'll need to provide at least some sources, and they have to be published professional philosophers. You also need to keep your own personal comments and opinions out of the article. SlimVirgin ^(talk) 19:38, 6 March 2006 (UTC)

SlimVirgin you have violated another standard of wikipedia by disrupting the work of several editors to make a point. [2] The reversion took place after your discussion with the before-said editor over similiar inappropriate behavior elsewhere. This is further proof of your violation of wikipedia rules, and the violation of your position. I request you ceast and desist in your harassment here and let the editors who have put many hours into this page, alone. To revert an entire article is un-called for and I DEMAND a verifiable reason for what you have done. --Northmeister 02:13, 8 March 2006 (UTC)

• More specifically, what do you SlimVirgin consider to be Original Research, please indicate here so Ted has a chance to state his case.
• Second, what do you consider not verifiable according to the policy on such?
• Third, what sources do you challenge on this subject? Please show this community what particular parts of this article you consider to violate the above, since you seem to indicate that the above rules were somehow violated.

Civility is a cornerstone of understanding and respect. Good Faith presumes that Ted was acting as such when editing this article. Good Faith should be shown by yourself and any others who wish to challenge this article. Therefore present your case so Ted knows what your talking about and then let CONSENSUS determine what is to be changed or what is not right. --Northmeister 02:51, 8 March 2006 (UTC)

I further find it offensive that you bring material from a previous edit up as if it were a recent edit to scold an editor. This is not proper. The edit in question by you (SlimVirgin):

• "Formal logic is a complex game. And I do mean game ..."

The above sentence was changed by Kazvorpal on 19 January 2006 [3]to:

• "Formal logic is a complex game. Literally a game,"

This was accepted by Twrigley until an improvement was made by him on 05 February 2006 [4]to read:

• "A syllogism's ability to explore errors of reasoning, however, relies on its structural validity. Not every trio of propositions creates a valid syllogism, and often - particularly when variant moods and figures are involved - the validity of a syllogism becomes ambiguous and difficult to ascertain. e.g.:"

This reading has been accepted since it was added into the article on that before said date. Since then the following users have helped to edit the article: Ancheta_Wis, Chalst, Mhss_en, Brian0918; including the following anonymous users: 66.26.38.109, 71.136.83.144, 70.242.141.195; and did not dispute the change made by Ted.

I ask that you present reasonable instances to the community of error in this article or that you stop your efforts at disruption and allow those editors mentioned earlier to edit as they were in the wiki fashion of collaboration and consensus. I am sure this article is not perfect, but no article at Wikipedia is. --Northmeister 04:27, 8 March 2006 (UTC)

Rewrite

Sorry if I've seemed to bull in and do a major rewrite without consultation, but as it stood the article was in dire need of help. The term "Barbara", for example, was introduced with no explanation or context, and I doubt whether an intelligent reader who was ignorant of the subject would have been any the wiser (actually, even someone who did know something of the subject would have been puzzled at points). The last section, on validity, is also a bit of a mess (confused, obscure, bitty), but I ran out of time. I'll be back soon, though if anyone else wants to pitch in... --Mel Etitis (Μελ Ετητης) 22:17, 6 March 2006 (UTC)

Thank you, Mel. That's a huge improvement. SlimVirgin ^(talk) 22:38, 6 March 2006 (UTC)

Where did Baralipton go from the list? — ₀₉₁₈^BRIAN • 2006-03-6 22:46

Baralipton is an indirect mood (like Frisesomorum, Fapesmo, Dabitis, etc.); I'll add a section on those, but this was a first go, and meant to be simple and straightforward. --Mel Etitis (Μελ Ετητης) 23:04, 6 March 2006 (UTC)

After double edit conflict:

Ah, I've just looked at the History, and found this version. It's better than what I replaced in many respects, though it too often reads like a (somewhat facetious) personal (and PoV) essay, and goes into rather too much detail for an encyclopædia article on some matters (History pf logic would be a good place for a lot of it). If this had been in place when I came along, I'd have still wanted to subject it to a good shave and haircut, though I'd have been less inclined to replace it wholesale. Perhaps some compromise can be found, adding material from the version in history to what's now in place?

As this is specifically and only about the syllogism, though, we need to be careful not to overdo the general history-of-logic stuff. --Mel Etitis (Μελ Ετητης) 22:56, 6 March 2006 (UTC)

hey, Mel, Slim. Suit yourselves. if you want this page, it's yours. might as well start renaming this place crapipedia... later. Ted 22:58, 6 March 2006 (UTC)

oops. We need a process, that is clear. Some civility is called for here. It is probably discomfitting when the electric fence shows up, but we eventually reveal ourselves when we edit here long enough. When the articles reach stability, all too often the consensus is unspoken although real. This could all have been avoided with a general call for approval on the talk page, periodically. Please don't feel too aggrieved; it would probably be best if you simply retracted the above. If you do so, you have my permission to delete my statement as well. Peace. But we have just crossed a line here. Perhap we need some breathing room as well. --Ancheta Wis 23:11, 6 March 2006 (UTC)

OK, perhaps I was wrong about compromise, and thinking that we could all work together. Still, if other editors would care to join in? --Mel Etitis (Μελ Ετητης) 23:04, 6 March 2006 (UTC)

Mel, please, neither you nor Slim showed any interest in this page until after I got in a tiff with her. and I really don't want the to badger either of you about. it saddens me that the two of you would go out of your way to muck up a page just to try to punish me, so I'm hoping that if I stop participating for a while you guys will come to your senses. drop me a line if you care to discuss things, otherwise I'll check back in in a month or so.

Ted 23:09, 6 March 2006 (UTC)

No one's "punishing" anyone. It was just that the version that was on the page before I reverted was too much of a personal essay, and the one that I reverted to was inadequate. As Mel says, somewhere in between would be ideal, being careful to leave out personal opinions, or else attributing them to a published source. SlimVirgin ^(talk) 23:12, 6 March 2006 (UTC)

No, you have violated Wikipedia rules of civility by reverting hours of work by an editor. You have disrupted this page to make a point, among other things. As above you are in violation of [5] and I ask you stop harassing Twrigley because he mediated a case in which you would not participate. It is uncalled for. If an editor has a problem with a portion of this article, let that individual editor present his case here and with civility work out the problem with Twrigely who has put hours into this. --Northmeister 02:27, 8 March 2006 (UTC)

What's happened?

We have now lost the whole of the original article on term logic - here is a recent version.

[[6]]

At some point it was turned into a rambling essay, then got merged with syllogism, then SlimVirgin cut it down completely. I agree some that some reduction was necessary, but now we have lost all the stuff on why there are two terms in the proposition, what terms are and so on. Dbuckner 12:30, 7 March 2006 (UTC)

Would it be acceptable to revert to the term logic Revision as of 03:41, 20 January 2006 and disconnect from this article, for now? Anyone? --Ancheta Wis 13:38, 7 March 2006 (UTC)

Well not really, as Mel's rewrite of this article is quite good, and the old Term logic did overlap a lot. I need to think of a way to bring in the material that was lost. Dbuckner 13:57, 7 March 2006 (UTC)

Twrigley, by all means start merging back some of the old version (in consultation with the other editors), but please don't delete Mel's additions, because they really are improvements. SlimVirgin ^(talk) 13:29, 8 March 2006 (UTC)

I agree with "Slim Virgin". I wrote the article "Term Logic" some years ago when WP style was chattier. Since then additions were made that were stylistically awful, and I'm happy to see it go in the dustbin. Plus, Mel's rewrite is high quality stuff and we should keep it. So, Ted, please be constructive about this. Dbuckner 08:54, 9 March 2006 (UTC)

Versions

this page has been reverted to it's state before this argument began. please see my discussion with Mel Etitis on my talk page, here. Mel, since you agree that the original version was superior to the version you found on your first edit, I suggest that we begin revisions (however extensive you would like those to be, beginning here.

I agree with your comments on wordiness, and while I disagree in strong terms with SlimVirgin's claims about personal essays, I'm willing to discuss the matter. her actions, however, destroyed far too much new and worthwhile content to be considered appropriate.

shall we discuss a plan for revisions, or simply feel our way through the process? as I said, I've had ongoing discussions with two other established editors of this page about changes, and there's no need for particular hurry in the matter. — Preceding unsigned comment added by Twrigley (talk • contribs)

Ted, your discussion with Mel on his talk page shows that he agrees some of the old version should be merged into this one, but not all of it, because as he said some of the old had POV problems and parts were written in an unencyclopedic style. Mel has said that once his busy period is over, he'll be able to start collaborating on transferring material from one version to the other. I think you should wait for him to do that, because you'll probably end up with a great article as a result. SlimVirgin ^(talk) 13:42, 8 March 2006 (UTC)

SV... thank you: I'm more than happy to collaborate with Mel. however, I personally feel it's much better to start with a relatively complete page and pare it down, than to begin with a skeletal page and build it up. you are free to disagree, and we can discuss this if you like.

but it appears from the immediate reversion that you've marshalled people to make sure that we do it your way. that's cool. very bad faith on your part, but none of my business. Ted 13:56, 8 March 2006 (UTC)

• I've just seen that User:Twrigley has reverted the page (twice) with the extremely misleading edit summary "rv. per discussion with Mel. please see discussion on talk page". Even if he's using "per" in an extremely non-standard way, I find it very difficult to assume good faith with regard to this; nothing in what I've said here or on his Talk page comes close to justifying a reversion (quite the contrary). I shall continue to make use of his material when expanding and up-dating the article, but it seems clear that he's not in fact interested in collaboration. I think that that's a pity, but it's silly for me to use up further time and energy trying to achieve an amicable joint approach given his behaviour, so I'll leave it there, and spend the time trying to improve Wikipedia. --Mel Etitis (Μελ Ετητης) 21:55, 8 March 2006 (UTC)

I reverted originally and just now, because SlimVirgin broke rules of civility and her administrator discretion by reverting an entire page she has never engaged in or had been asked to look at. She did this after a mediation case in which she was accused of breaking other rules and defining wikipedia arbcom cases against the wishes of Jimbo Wales. She refused the mediation. Ted got involved in that indirectly as the one who chose to mediate as he was on the Mediation Cabal as it is called. He was attacked by SlimVirgin for his decision done in fairness and honesty. SlimVirgin immediatly came here and reverted days! of edits. You arrived after this and put in hours. I appreciate your work Mel, and offered a suggestion you work with Ted from his original version which did need work. SlimVirgins explanations for reverting an entire work of material were not appropriate as I've shown above. She has failed to answer my legitimate questions. As a wikipedia editor I have every right to question anyone who acts in this manner. I expect answers from her abuse of Ted still. You have been hostile towards me, understandable if you thought I was directing the reversion against your edits...I was not. I actually approve of your edits, but I had to right a wrong when it came to Ted from SlimVirgin who was abusing her role here and continues to do so. My suggestion again, is to work together with Ted, the both of you could put together a wonderful and accurate article. I will continue to uphold his version and insist according to procedures here at wikipedia, that you show sentences you disagree with and show us here in the community your changes with citations, if you refuse to collaborate with Ted who has spent days on this before the unwarranted reversion. --Northmeister 00:38, 9 March 2006 (UTC)

Northmeister, you're trolling, pure and simple, and have no knowledge of or interest in the subject matter, so please give it a rest. SlimVirgin ^(talk) 02:36, 9 March 2006 (UTC)

SlimVirgin, I am trying to defend someone who tried to help wikipedia out through mediation and who was 'punished' by yourself through reversion. Please answer my questions above. I have every right to discuss this article since your reversion, since that is the topic here, unneccessary reversion. You should of discussed why you wanted to revert before you reverted. You should know this, and the fact you have been around awhile, makes this doubly so. I want civility here. I request in all good faith that you stop 'harassing' Ted and allow this page alone to be edited by those who were working on it before your reversion. I remind you in this official manner: I see you have been experimenting with Wikipedia. Your change was determined to be unhelpful, and has been reverted or removed. Please use the sandbox for any tests you want to do. Take a look at the welcome page if you would like to learn more about contributing to our encyclopedia. Thanks., that reverting an entire page without prior notice or any Good Faith observations of Ted is wrong. You should know this. My interest in this page will end when the 'harassment' and abuse ends. It looks as if Ted left because of what you did, and what Mel has done since your reversion. I extend good faith to Mel, maybe he is an innocent bystander who decided to edit just at the wrong time, not sure, so he should understand that my reversion was done to fix a wrong, and work from the original article with Ted to improve it. We both (you and I SlimVirgin) should stay out of it. --Northmeister 02:45, 9 March 2006 (UTC)

None of this protracted ad hominem addresses the important question of the relative quality of Mel's work versus the quality of the work he replaced. My judgment is that Mel's work is better (I have studied syllogistic and traditional logic for nearly thirty years). By a long way (see my comments below). I'm sorry if anyone has been offended or upset, but at the end of the day we are trying to write a quality encyclopedia, and the sections on logic and philosophy need all the quality they can attract. So please: chill out. Dbuckner 09:26, 9 March 2006 (UTC)

Yes, I agree a quality article is the most important. Your statement below is incorrect. SlimVirgin reverted an entire article and Mel came in right after that. Mel's contributions are excellent, but the work of Twrigley was also well done. I've seen no real explanation that Twrigley's work on the article was wrong. The first standard of an encyclopedia is getting it right. The second is writing it straight. Everyone says Twrigley got it right, including SlimVirgin. Even Mel acknowledged a better version that was interestingly Twrigley's. The point then is to restore that better version by his own admittance and then include the changes Mel wishes to make. First we right the wrong done by SlimVirgin. Then we collectively replace any material that Mel has done better into the article to improve it. Thus we have structure, fairness, and cohesion to the entire process. I restored Twrigley's version. Mel now may edit that original article that was vandalised with any better material. Let's do this paragraph by paragraph as a starting remedy. The end results will clearify all disorder and restore vitality and accuracy to wikipedia and this article. Let us engage. --Northmeister 14:43, 9 March 2006 (UTC)

Suggestion

Some more thoughts. I've read again through the edit that "Ted" and "Northmeister" want to revert. Their complaint is that a lot of material has been deleted by Mel's rewrite, which is true.

Bit I would NOT want to lose Mel's rewrite, as this deals with the syllogism in a compact and efficient way. He introduces the syllogism with a short definition, moreover in a way that defers to Aristotle in the medieval style. Then he introduces the idea of major and minor premiss in an economical way, by the key concepts of major, minor, minor and middle term. Nearly all you need to know about the syllogism is in the introductory paras, which is the essence of good writing. So, well done Mel.

However, the problem is that 'Traditional Logic' is a far wider area than just the syllogism, and the original article 'Term Logic', which was (cursory) attempt to deal with the wider subject, is now completely lost. Can I therefore suggest that this issue is dealt with in the upcoming rewrite of all the logic pages, which Charles Stewart ((talk) ) (an accomplished logician) and myself (a not so accomplished logician, but I do have a detailed knowledge of the history of logic). Rather than get into a protracted edit war, can I suggest that solution.

I.e. in SUMMARY: keep Mel's rewrite, but work towards a proper organisation of the logic pages, and moreover work together without these protracted and silly arguments. Yes? Dbuckner 09:26, 9 March 2006 (UTC)

Speaking for the bystanders, thank you for your precis. Might we see a sketch of a roadmap for the logic pages at some time? That might even attract others to the pages. --Ancheta Wis 10:27, 9 March 2006 (UTC)

Yes. At the top we have the article on Logic. The idea of the recent rewrite as proposed here User:Dbuckner/logic was to emphasise the elements that 'traditional' logic have in common with 'mathematical' logic (of schema and logical form, of inference and validity and so on).

The article Organon should cover precisely what Aristotle covered in the books now called by that name. I have done some work on the sub-articles such as Posterior Analytics, but I slapped on a 'developed or reviewed' notice on Organon itself as there are numerous inaccuracies.

There should be an article Aristotelian Logic. This should cover the 'Peripatetic' logic of the Middle Ages, including the additions (such as the theory of consequences, supposition theory, the theory of mental language and so on).

There ought to be something on Traditional logic, covering the period from Arnauld to Mill, as this is fairly distinct and leads naturally into modern logic.

Regarding modern logic, there are already some very good articles, e.g. Mathematical logic, on the mathematical logic side. It is less good in the area of Philosophical logic however. I have contributed ad hoc articles – a complete rewrite of Existence for example, plus Plural quantification and some others, but there needs to be more work here. Enough? Dbuckner 11:53, 9 March 2006 (UTC)

A further problem is that any of the more general subjects such as Truth will come under attack from the Usenet fringe. I'm surprised Existence hasn't yet. I'm hoping that Logic is enough of a specialist subject to avoid detection by elements who imagine that generality of subject matter is an excuse for ignorance of it. A notable casualty of this is the Philosophy article, which genuine philosophers such as Mel have avoided (end of sermon). Dbuckner 11:53, 9 March 2006 (UTC)

As per by latest statement

Let us engage. Paragraph by paragraph, Mel offer your rewording here for the community to consider both paragraphs and to work with yours and Twrigley's for accuracy and detail. Together much can be accomplished. --Northmeister 14:46, 9 March 2006 (UTC)

I will start with the first two opening paragraphs which in my opinion are much better for their historical background and for lay-person wishing to understand this page, like myself works better. Here is the paragraphs:

"Syllogisms are the cornerstone of the logical tradition, known as term logic or Aristotelian logic, that originated with Aristotle (see Prior Analytics, Book I, c. 1.) and survived broadly unchanged until the advent of modern predicate logic in the late nineteenth century. A syllogism (Greek sullogismos, meaning deduction) consists of three interrelated propositions, in which the last proposition is shown to be necessary if the first two propositions are true. Occasionally these are called categorical syllogisms because the propositions they contain involve relatively simple declarations about categories, objects, and the properties that apply to these categories and objects. Syllogisms are usually considered to be a form of inference, but the inferences drawn in syllogisms are generally viewed by nominalists as trivial and tautological. Instead, syllogisms are used to examine the validity of reasoning involved in a given statement by exposing questionable assumptions and incorrect category relations. This article provides an introduction to syllogisms (categorical syllogisms, term logic), giving some historical background, a description of the basic use and structure of syllogisms, an analysis of common errors in reasoning, and suggestions for further reading.

Non-categorical syllogisms deal with the truth values of proposition in relation to other propositions, rather than looking at their internal structure of propositions as is done here. Propositions are taken as single, non-decomposable elements in non-categorical syllogisms, each with a given truth value, without considering internal validity or derivation. See disjunctive and hypothetical syllogisms."

Considering the above two paragraphs, what within them needs changing to improve these two. Let us engage in discourse and improvement. --Northmeister 14:52, 9 March 2006 (UTC)

1. In the tradition referred to the conclusion is not 'shown to be necessary' it 'results of necessity'.

2. The explanation 'These are called categorical syllogisms because the propositions they contain involve relatively simple declarations about categories, objects, and the properties that apply to these categories and objects.' is not a very good explanation. It presupposes understanding of 'categorical'. (Actually Mel's is not much better here).

3. 'inferences drawn in syllogisms are generally viewed by nominalists as trivial and tautological' – there is a grain of truth in this, but presupposes a much wider debate which it would not be wise to bring in at this point.

4. " Non-categorical syllogisms deal with the truth values of proposition in relation to other propositions, rather than looking at their internal structure of propositions as is done here. Propositions are taken as single, non-decomposable elements in non-categorical syllogisms, each with a given truth value, without considering internal validity or derivation. See disjunctive and hypothetical syllogisms." This is incomprehensible.

5. Much of the rest of the article comes from the article I wrote in September 2003 which is [here], and which is much broader in scope. I have already said I do not mind if it falls by the wayside for now.

6. Northmeister: please stop this mindless reverting. You left a message on talk page saying "my sense of justice precludes me from starting anywhere than Twrigley's original article". Most of this is not Twrigley's, and my view, if you forgive my saying, is that he did not improve what I had originally written (quite the reverse). Dbuckner 15:28, 9 March 2006 (UTC)

As evidence of this, Twrigley wrote in a previous edit. "Formal logic is a complex game. And I do mean game - in its intricacies it resembles the world's best crossword puzzle. For the most part, these intricacies develop from difficulties with variant category constructions: subsets, negations, exclusions. e.g." Dbuckner 15:34, 9 March 2006 (UTC)

Dbuckner, I didn't have time to photoshop an LCD monitor into Rembrandt's picture. But I can see a phone on the desk and a printer in the window. Please reconsider leaving the encyclopedia. Regards, the lot of us.

In fact if any more of this nonsense goes on it will be me who leaves Wikipedia. I've had enough of it. Philosophy was bad enough. My professional work involves drafting complex documents using teams of people. To do this we hire people with proven ability by a complex system of exams and work experience. This works. The idea that you can do the same except without the qualifications is completely mad. Wikipedia was a brave social experiment. It has failed. Dbuckner 15:34, 9 March 2006 (UTC)

I actually share your sympathies above. The social experiment of wikipedia is failing and the example of what has happened to me (per history articles-my field of expertise) is sad. My attempt to defend an innocent bystander from disruptions and ill-will seems also to be failing. That is all true. As I have stated often, I do not debate the contents, but the wrong done. There is no need to bring the above statement up again, I already questioned SlimVirgin for doing so, since this statement was changed after it was written weeks ago. My proposition that we -right the wrong done by SlimVirgin and work from there, is out of sense of justice. Then as a community, Mel, yourself, Ted (if he ever returns) can work together to improve this article. That is how wikipedia works, to get it right through collaboration and consensus. I do not wish to argue continuously. It is as if no one listens, but simply responds. No war exists here. Simply a struggle to right the original wrong, use Mel's improvements, and your thoughts on the subject to improve the article. I got involved here because of what SlimVirgin did. This is your range of expertise, and when the wrong is righted and the community works together, achievement can result. Only the few make it harder on the rest of us. But the many, united together in common hope, with evidence and facts, can through the rule of consensus progress toward works of excellence. That is what we came here for. You came here and I, to offer our expertise, to engage with the community at large to put together a free-encyclopedia that the world could turn to and gather information from for their studies; to build together and work out our problems through citations and fact. We came because we love knowledge, we are pushed around by the few, who have ruined our experience. But they are the few, that very small few, and once recognized for their actions, the many who want harmony and truth, can united to prevail for that truth, that justice, that Wiki-way. Let us not turn back but forward and face this situation with all that brought us here. Let us work together and as a community and overcome the small molehills that like a mirage in the blinding sun of the desert, looks as if it were a mountain. --Northmeister 15:52, 9 March 2006 (UTC)

Northmeister, it appears that Mel, Dbuckner, Charles Stewart, and Ancheta Wis have the expertise needed to write a good article based on Mel's version, while retaining the good material in the previous version. Please allow them to get on with that. SlimVirgin ^(talk) 16:11, 9 March 2006 (UTC)

Nonetheless Then I leave Wikipedia, after many years of work, and many articles on philosophy. Just to be clear, it is because of people like you [Northmeister], who say (your words) "I do not debate the contents, but the wrong done". It's not clear that any wrong was done here. Mel, who is a professional philosopher and a good writer, reverted an edit by someone who is not a professional philosopher, and is not a good writer. What's wrong with that? And in any case, the most important thing is the contents. I'm fed up with working with people like you. Dbuckner 16:19, 9 March 2006 (UTC)

I'll come back when there is a decent editorial policy. It's unfair that people who have some sort of respect within their peer group, have to put up with this constant low level of aggregation. It was not like this when I started on WP. The lunatics will eventually take over the asylum. Dbuckner 16:19, 9 March 2006 (UTC)

ME? Mel did not revert first. Check the edit history. It was SlimVirgin. Your arguments continue to state fallacies. You have the personal choice to leave. To blame my defense of someone who was wronged by SlimVirgin (who has wrong others in the past), on your leaving based on your false assumptions above, is specious at best. People like me? What sort of person am I to defend a fellow editor from abuse? What sort of person am I to right a wrong done to Ted after SlimVirgin was ruled against in a mediation case and responded in kind here to revert his entire work? What does that make me? I concur about editorial policy, there is actually a decent one, just the few like SlimVirgin who abuse their positions by what she has caused and done here at this page. Look at the results of it. Had she not violated 'don't disrupt to make a point' this whole thing would not be occuring, as I would not be here trying to defend a good and honest editor who was abused by her. Am I a lunatic by your accusation? If defending others from abuse is lunatic then I am guilty. If attempting to defend wiki-policy on decency and 'do not disrupt' makes me a lunatic, then am I am guilty. If attempting to right a wrong done by SlimVirgin here makes me a lunatic, then guilty. Why are you so hostile towards me? I've never been hostile towards you? It doesn't make any sense. I've called for harmony and working together and I am accused of being a lunatic, once again guilty as charge, if that is the definition. --Northmeister 16:45, 9 March 2006 (UTC)

last comments before I leave for good

I am finding this entire experience exceedingly unpleasant, and so I have decided to leave the Wikipedia community. I'm just waiting for some responses on a couple of issues before I finalize that. I would, however, like to make a few last comments re: this page before I go, which will hopefully settle some disagreements.

Dbuckner, Mel

I wouldn't disagree with you on most of your points. My issue is not with Mel's rewrite, or with DBuckner's desire to re-separate the Syllogism and Term Logic pages. My objection is to SlimVirgin's crass exportation of a personal vendetta into article content. It's a pity that the syllogism page got caught up in that. I will say that the one line you keep bringing up "Formal logic is a complex game. And I do mean game - in its intricacies it resembles the world's best crossword puzzle. For the most part, these intricacies develop from difficulties with variant category constructions: subsets, negations, exclusions. e.g." is one I probably would have cut out myself, except I forgot I put it in. Well... the second half is actually true, if maybe a little on the NOR side... but in itself this was not grounds for reverting the entire article. Frankly, under other circumstances I would have loved to work on the article with both of you, but... I just don't like it here.

Northmeister

If you respect me, and respect that I honestly tried to help you on the other page, please do not bring the fight with SlimVirgin here. Let it be, and let the people who really want to reconstruct the page get to work. I will not be working here, and if you leave as well, SlimVirgin will have no further reason to be here either. She won't control herself (she's not capable of it), so it's up to you to be the responsible one. Ok?

Ancheta, and other observers

My apologies for all this. I got some crap stuck on my shoe in a different context and it dragged itself in here after me. Not much I can do about it, but I do feel bad.

SlimVirgin

Since I'm leaving, I feel free to tell you that you are one of three people in the world that I have reason to disrespect utterly. You have no perspective, no self-discipline, no sense of context, and no sense of decency or propriety. Go away, you're useless.

Administrator trolls, I swear... and you wonder why the social experiment is failing here? Ted 18:29, 9 March 2006 (UTC)

• Thank you for bringing this talk page to the level of MySpace. It is what we have been striving to accomplish. Wikipedia is not a social experiment. It is a site that uses social software to create an encyclopedia. If you want a social experiment, check out MySpace or LiveJournal. I highly doubt the staff of Encyclopaedia Britannica throws nearly as many "hissy fits" as those on Wikipedia. — ₀₉₁₈^BRIAN • 2006-03-9 19:29

<shrug...> I play the cards I'm dealt, my friend. I wish that Wikipedia were what you hope for, and I hope it reaches that state some day, but I recognize a fold hand when I see it.

I do Ted, and I will not intervene here any longer. Sorry to see you leave. Good wishes and luck in the future. --Northmeister 22:09, 9 March 2006 (UTC)

Merge/rewrite project

For those who want to work on the article using the version before the version before my rewrite, I've moved it here. My feeling is that a lot of the material would better moved to Term logic or even to Mediæval logic, but some of it certainly belongs in this article. --Mel Etitis (Μελ Ετητης) 10:03, 13 March 2006 (UTC)

That's well done, Mel. There had almost been an edit war here

Patrolling the ocean called Wikipedia|Tell me about vandals, violations and more... 13:38, 13 March 2006 (UTC)

Types of ... Gibberish?

Sorry to tell you folk, but, at the moment, everything from "Another classification" in Syllogism#Types of syllogism until the start of Syllogism#The place of the syllogism in logic is unexplained, out-of-context, near-gibberish. What is the table for? What is being explained? Who are Barbara and her friends? Please tell us, in plain english please, what you are hoping to tell us here.

After a bit of Googling I think I've been able to clarify it. What seems to be being explained is that there are a finite number of types of syllogism and the article discusses the categorisation scheme for them. Barbara and so forth are mnemonics for the types of valid (logically correct) syllogism. I'll add an example of each type if I can find the time.

It would be nice to have an explanation of why A, E, I and O.

--Ekaterin 12:37, 7 August 2006 (UTC)

The article explains what you were able to find using Google. As for why A, E, I and O, according to Irving M Copi, Introduction to Logic, third edition, The Macmillan Company. (1960):

The letter names are presumed to come from the Latin words "AffIrmo" and "nEgO," which mean "I affirm" and "I deny," respectively.

I've added a note to this effect to the article.

Paul August ☎ 19:01, 7 August 2006 (UTC)

Doesn't sound right to me. Was the choice of A,E, I, and O random? Could any of the other letters of the Latin words have been chosen? It would be different if they were the first letters of the Latin words. But, the letters of the first Latin word are the first and fourth letters. The letters of the second Latin word are the second and fourth letters. There is not even a pattern. It is more likely that they were primarily chosen simply because they are the vowels in well-known order. The Latin words are merely a mnemonic, as an afterthought.

The vowel letters … are symbols or abbreviated names, which are always used to denote the four kinds of proposition; and here will be no difficulty in remembering their meaning if we observe that A and I occur in the Latin affirmo, I affirm, and E and O in nego, I deny.

— William Stanley Jevons, Elementary Lessons in Logic, Lesson VIII

Lestrade

Alternative syllogy

What about the famous parody on these logical examples:

One cat has one tail more than no cat.
No cat has nine tails.
Thus, one cat has ten tails.

What is this an example of? 惑乱 分からん 23:13, 15 September 2006 (UTC)

The negative phrase "No cat" is being misused as a positive concept. Happens all the time.Lestrade 13:40, 19 September 2006 (UTC)Lestrade

inconsistent opening paragraphs

Hi, I can see that there has been a lot of discussion in this page here, and that the page has gone through numerous rewrites. However, this opening part is blatantly inconsistent and very confusing:

"In Aristotle, each of the premises is in the form "Some/all A belong to B", where "Some/All A' is one term, and "belong to B" is another, but more modern logicians allow some variation. Each of the premises has one term in common with the conclusion: in the case of the major premise this is the major term, i.e., the predicate of the conclusion; in the case of the minor premise it is the minor term, the subject of the conclusion. For example:

Major premise: All men are mortal. Minor premise: Socrates is a man. Conclusion: Socrates is mortal. "

So we read that "each of the premises is in the form "some/all A belong to B," and then we are given the example premise "Socrates is a man." Uhhh, what???? Fix this please. It may just take something as simple as "Socrates is a man is actually technically rendered in a syllogism as 'All things that are Socrates are men," but please clear this up.

One serious problem with this language is that it completely reverses the sense of "belongs" (inherited from Aristotle's terminology in Greek). When Aristotle says, "A belongs to B" (or more precisely what's usually translated as that), what it means is "A is true of what B is true of", or if you like "Things that are B are also A", or to be absolutely traditional, "Bs are As". In other words, in "A belongs to B", A is the predicate term and B is the subject term. It would be accurate to say "each of the premises is of the form "A belongs/does not belon to all/some B" (if a little awkward), but it is actually nonsense to say something like "Some A belong to B" (that would be equivalent to "Bs are some As").

For purposes of exemplification, the example given is also very misleading. The categorical syllogistic requires that every term be a general term, i.e. something that can be used as a predicate. "Socrates" is not such a term: it's a singular term, i.e. a name. The sentence "Socrates is mortal" can't easily be classified as universal ("All Socrates is mortal"?) or as particular ("Some Socrates is mortal"?). There's a long history of discussion about just where to put singular terms in any version of the syllogistic, but in any event "All men are mortal, Socrates is a man, therefore Socrates is mortal" is actually a poor example of a categorical syllogism,---Robin Smith

May I second the above -- as a visitor who also found that passage obscure in an otherwise illuminating article.

A second inconsistency appears in the baroco (A-O-O) example:

All informative things are useful.

Some websites are not useful.

Some websites are not informative.

Surely, the minor premise and conclusion need to be reversed here?! In the major, 'informative' is a subset of 'useful' but not (necessarily) vice versa. So while uninformative websites are not useful, there is no reason to believe that useless websites might not still be informative. Syllogistically speaking. 212.248.167.53 22:35, 24 January 2007 (UTC)Estragon

I agree with the original comment - in default of a detailed explanation about how singular nouns ("Socrates", in the example) are considered to refer to their entire extension in a syllogism, perhaps a change to "All humans are mortal, All philosophers are human, All philosophers are mortal" might be in order. On Estragon's point, this is in fact how Baroco works - a perennial problem with all the second, third, and fourth-figure syllogisms. We can reduce it to a first-figure syllogism (Ferio) by contraposition of the major:

No non-useful thing is informative

Some websites are non-useful

Some websites are not informative.

Tevildo 11:38, 22 April 2007 (UTC)

I also propose to change the "Basic structure" section to just include a canonical example of a perfect syllogism. The "All greeks are human, all humans are mortal, hence all greeks are mortal" would be a viable candidate. This article discusses Aristotle's syllogism, and Aristotle just admits universal terms in his system. Let's shift the discussion the use of singular terms like "Sokrates" in syllogisms into later section, since it is an extension to Aristotelian logic. Łukasiewicz who is mentioned as reference in this article makes a big point in making clear that there are no singular terms in Aristotelian Syllogistic.

Further the opening section would more accessible, if just gave a short description of a syllogism without discussing special cases. Der lunz (talk) 16:09, 14 August 2008 (UTC)

Frege

The logic that Frege invented was second-order not first-order. Both he and Pierce produced second-order logics at around the same time. That students are now taught a first-order variant of Frege's logic is because it was subsequently discovered that second-order logic has certain limitations that are not present in first-order logic. One of the key benefits of Frege's logic was its ability to deal with the problem of multiple generality in a way that Aristotelian logic could not. As a starting point, Wikipedia articles on multiple generality and quantification touch on this point.

Ok, it was corrected! Cyb3r (talk) 17:58, 25 May 2008 (UTC)

Datisi type explanation

Hello,

First of all I'd like to third' the above statements and mention that the opening is indeed confusing and possibly wrong.

Secondly I believe that Datisi under the paragraph Types of syllogism is wrongly stated. Currently is stands as following:

Datisi

   All the industrious boys in this school have red hair.
   Some of the industrious boys are boarders.
   Some boarders in this school have red hair. 

Doesn't this give of the wrong conclusion. This example assumes that there are red haired boarders in the school.

If it sais "Some of the industrious boys IN THE SCHOOL are boarders." than the conclusion would be valid.

A valid point - appropriate changes have been made. Tevildo 16:18, 13 May 2007 (UTC)

Set diagrams and four dimensional structure

The fifteen syllogisms valid in modern logic, represented in the diagrams below, correspond with a four element sets non empty subsets. Is anyone able to explain this curious matter?

Error between language and logic

Consider the following claims: "All humans are not perfect / No humans are perfect." In my opinion, they are different or at least can be interpreted differently. When P is "the object is perfect" and A is "for all humans", the first sentence says -A: P (A = "for all", P is a statement), in other words "it is not true for all humans that they are perfect". The second says -E: P, "there is no human for which holds: he/she is perfect" which has the same value in logic as A: -P. Careful consideration: is there an error or is it just me?86.50.9.167 (talk) 21:30, 27 April 2008 (UTC)

File:Syllogism-Tesseract.jpgFile:Logictesseract.jpg
000L: Modus Darii00L0: Modus Datisi00LL: Modus Ferio0L00: Modus Disamis0L0L: Modus Festino0LL0: Modus Baroco0LLL: Modus CelarentL000: Modus DimatisL00L: Modus BocardoL0L0: Modus FerisonL0LL: Modus CesareLL00: Modus FresisonLL0L: Modus CamestresLLL0: Modus CalemesLLLL: Modus Barbara

Apart from this four dimensional structure, the fifteen diagrams make syllogisms more easy to understand, and could be integrated in the article. Red indicates, that one or more elements exist in this area, black indicates, that an area ist empty. White areas might contain elements or not, and are thus of no importance.

The Venn diagrams are useful to visualise the syllogism itself, and are easily transformed into Euler diagrams visualising just its conclusion. This transformation is shown in the left image below. Greetings...

File:Modusbarbara.jpg