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Aristotle's syllogism.

javi2541997 March 26, 2021 at 15:26 7150 views 17 comments
Aristotle defined the syllogism as an argument in which, establishing some things, it turns out necessarily what they are, a different thing from the last ones.
Syllogism appears to be a law of logics. Classic example: If A is part of B and then B is part of C... C is necessarily part of A.

We can categorise syllogisms in many ways as possible. But somehow, Aristotle, back in the day established the so called perfect syllogism also named as axiom. Thus, an evident argument that cannot be refuted due to pure logic.

So, following Aristotle principle I only have in mind this perfect syllogism as possible:

[u]All humans have limit lives and are deadly (higher premise)
I am a human. (lower premise)
Therefore, my life is limited and I am deadly (logic conclusion that cannot be refuted because this literally happens)[/u]

Then, ending the study of perfect syllogisms, I cannot make or think about others. I guess there is not another perfect one as this. Because is clearly our lives are so limited and therefore deadly.

Here is when I want to ask the illustrious members of this forum about other perfect syllogism and debate about it.

Comments (17)

Deleted User March 26, 2021 at 15:33 #514861
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javi2541997 March 26, 2021 at 15:39 #514867
Reply to tim wood
Start here. Do you see the problems?


To be honest. No, I do not see it.
Amalac March 26, 2021 at 15:44 #514870
Reply to javi2541997

Quoting javi2541997
If A is part of B and then B is part of C... C is necessarily part of A.


I guess you mean something more like: If A is part of B, and C is part of A, then C is also part of B.

One of my university professors (the same one I mentioned in one of my threads) mentioned a similar syllogism, and put into the mouth of a sceptic the following question: How do you know that all men are mortal?

In the first place, we can't know that with certainty until all men have died, and since that includes us we will never be able to know, since even if everyone else died we'd still be alive. And we can't even know with certainty that it is not the case that someone somewhere in the world is, say, 300 years old.

[quote=Bertrand Russell](...)there is nothing logically self-contradictory about an immortal man. We believe the proposition on the basis of induction, because there is no well-authenticated case of a man living more than (say) 150 years; but this only makes the proposition probable, not certain. It cannot be certain so long as living men exist.[/quote]


javi2541997 March 26, 2021 at 15:58 #514876
Reply to Amalac

No. I guess I am right because I am speaking about parts of one thing.
A is part of B. (so B has parts of A)
B is part of C. (B which has some parts of A, also has parts of C)
Then, C has parts of A because somehow it was dragged from the original roots.

Also I really like the quote of Bertrand Russel you quoted. Specifically:
but this only makes the proposition probable, not certain. It cannot be certain so long as living men exist.


It is interesting how he explains it. Of course we cannot argue against it while living men exist.
Amalac March 26, 2021 at 16:05 #514883
Reply to javi2541997

According to that logical structure:

1.Bricks (A) are part of a wall (B)

2.A wall (B) is part of a house (C)

3.Therefore, a house (C) is necessarily part of the bricks (A)

... which is obviously fallacious.

You then changed it to: C has parts of A, which is not the same as: C is necessarily a part of A.

javi2541997 March 26, 2021 at 16:12 #514892
Reply to Amalac

... which is obviously fallacious.

You then changed it too: C has parts of A, which is not the same as: C is necessarily a part of A.


I understand your point here but I guess I was typing the same but with more emphasis. Your example is even better than mine. C (the house) has parts of A (bricks) that have to be connected because they depend each other to build a house. So, C necessarily is part A since the moment where the house was built with the those bricks (A).
It is like a chain where the three parts are necessarily connected to build the house. They are not just parts
Deleted User March 26, 2021 at 16:17 #514893
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javi2541997 March 26, 2021 at 16:51 #514924
Reply to tim wood

I understand your point here. But you used another example. You are talking about A, B and C as indivisible things. I was trying to put an example of a syllogism which parts are some how related each other. This is why I guess Aristotle called it as perfect one
When I said A is part of B (we have here like a component)
B is part of C.
Then, necessarily C has to be part of A when B is already part of A
Like they end up being together.


There are a ton of good books on the subject, even cheap used. Try your library or ask an instructor for a recommendation. And if the book bores you to tears or is incomprehensible, get another book! This isn't rocket science and can be enjoyable as well as useful


Yes! I am looking for buying more like these but I think the issue here is that I am Spanish so I guess when I try to translate it in English by myself I go wrong. Anyways, I going to share with you a pic where I read it from because literally speaks the same argument as yours.

User image[/img]
Deleted User March 26, 2021 at 16:54 #514928
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javi2541997 March 26, 2021 at 17:00 #514934
Reply to tim wood
No. All A is C, some C is A.


Why some C is A? I am interested in this argument.
Deleted User March 26, 2021 at 17:18 #514943
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javi2541997 March 26, 2021 at 17:49 #514975
Reply to tim wood

Ok. I understand you now. Quoting tim wood
But this is why you need a decent textbook.


I will follow your recommendations. Thanks for helping me :up:
javi2541997 March 26, 2021 at 17:50 #514977
Quoting javi2541997
I want to ask the illustrious members of this forum about other perfect syllogism


Also this question is still opened :sweat:
god must be atheist March 26, 2021 at 18:45 #515008
Quoting javi2541997
I want to ask the illustrious members of this forum about other perfect syllogism


I'm illustrious enough so I will answer you.

Some Swedes are not Protestants.
All parishioners are Protestants.
Therefore some Swedes are not Parishioners.

This is the Holy Grail of all luminary syllogisms. This is perfect. Even Plato himself would include it as one of the Forms.

--------------

To be honest, there is no such thing as a perfect syllogism. It is like asking what the perfect two numbers are that you can add together to form a sum.
Deleted User March 26, 2021 at 19:13 #515022
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javi2541997 March 26, 2021 at 19:14 #515024
Quoting god must be atheist
Some Swedes are not Protestants.
All parishioners are Protestants.
Therefore some Swedes are not Parishioners.


Perfect one but somehow this can be refuted which is the main principle of perfect syllogism. I guess at least one parishioner is protestant. So this is why is not “perfect” enough. Nevertheless, when I put previously this one:
All humans have limit lives and are deadly (higher premise)
I am a human. (lower premise)
Therefore, my life is limited and I am deadly (logic conclusion that cannot be refuted because this literally happens).
This literally happens. This is why we cannot refute it because we all are deadly.

Quoting god must be atheist
To be honest, there is no such thing as a perfect syllogism. It is like asking what the perfect two numbers are that you can add together to form a sum.


I think name it as perfect is flawed. I am agree with you. But somehow it is difficult to find another exact syllogism as how deadly humans are. This is why I guess Aristotle named it in this way.
javi2541997 March 26, 2021 at 19:24 #515033
Quoting tim wood
If you mean other valid forms, here:

https://www.friesian.com/aris


Thank you Tim for providing to me these documents. I will check it out. Syllogisms are one of the topics I love the most in philosophy