Definition talk:Syllogism

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Wikipedia suggests that a syllogism has two or more premises - it may not be limited to exactly two.

Also, apart from vaguely dating from the same sort of time period and culture as the classical syllogisms, why is a Sorites in the "also see" here? From what I understand, a sorites is not a syllogism but a paradox, requiring the answer: at what point does a collection of sand grains become a heap? At what point does the last straw break the camel's back? and so on, easy to answer mathematically but brain-crushing to a muggle. --prime mover 14:45, 27 December 2011 (CST)

Okay I've always learned:
Syllogism: 2 premises, 1 conclusion.
Sorites: 3 or more premises, 1 conclusion.
Wikipedia has sorites as a disambiguation page, one for a sorites paradox that you're referring to, and one for a "polysyllogism". As for "2 or more", I disagree with wikipedia on this one, I just have to find the citation. I believe it's in Carroll's symbolic logic, which I don't have a copy of offhand, I've been using my school's copy and it's closed for the holidays. --GFauxPas 15:03, 27 December 2011 (CST)
Found a source for exactly two, I'll see if I come across any others I can use to build a fortress defending myself from angry wikipedians. --GFauxPas 15:29, 27 December 2011 (CST)
Hmm ... not sure if I'm being elitist here or not, but I don't know how seriously to take Carroll as a source work. The danger with going back to these historical sources (and in this context, earlier than about 1950 is historical) is that the language has changed, as have the mathematical tools to codify it. Bear in mind that when Carroll wrote his Symbolic Logic, he was still inventing the language. What he called a "thing" we now call an "object", but the concept originated with him, that anything could be the subject of a logical statement. Therefore a lot of what he laid down has been greatly refined since, to such an extent that the very techniques for solving syllogisms have been subsumed directly into predicate calculus which didn't even burp when it swallowed them. So it all becomes marginally relevant now, like the techniques originally used to find solutions to cubics so as to avoid invoking negative numbers.
Anyway, there is clearly more than one way to define a syllogism: some say one thing, some say another. Unfortunately, mere mortals are predisposed to take the first definition they encounter and treat it as the holy word of God. :-) The technique is to register all definitions found for a concept, under the banner: "Some sources say this, some say that, blablabla ..." In this context it matters little what definition you jump down on, they're all prehistoric anyway.
BTW you're safe from Wikipedians here, this is not Wikipedia.
I have it in mind to plunder Carroll properly sometime, but not at the moment, I find him boring. --prime mover 15:33, 27 December 2011 (CST)
I think you're right about being wary of Carroll, but I've seen it in more than one place. What I did with that book is basically read only the parts with editor's notes. I wasn't planning on adding too much on syllogisms because of the reasons you mentioned, but now I'm wondering if my "not too much" is perhaps too much. Fundamentally, the old traditional logic forms only a fragment of the new, a fragment moreover which, from the point of view ... of mathematics in particular, is entirely insignificant. - Tarski --GFauxPas 15:50, 27 December 2011 (CST)
I'm not saying "don't keep it in", what I am saying is "don't get hung up on supplanted definitions". The truths stay the same, the language they are couched in is updated. I was going to cover categorical syllogisms myself at some stage, but I keep finding myself with other stuff to do ... --prime mover 15:54, 27 December 2011 (CST)