Questions tagged [syllogism]
A syllogism is a form of deductive reasoning described by Aristotle containing two premises and a conclusion. Each of the premises and the conclusion contain a subject and a predicate.
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I need help understanding Sound reasoning! Deductive validity and truth
No arguments with false premises and a true conclusion are valid for If an argument is valid and the premises are true, then it's a sound argument.
no arguments with mood and figure IAI-4 are ...
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Aristotelian Syllogisms: Validity by reduction via reductio ad impossibile?
I'm trying to learn Aristotle's Organon but am finding Chapter 7 (volume I) of Prior Analytics difficult to comprehend, i.e., providing validity indirect (reductio ad impossibile) reduction.
Indirect ...
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In what work did Venn use his diagrams to analyze syllogisms?
In what work did Venn first use his diagrams to analyze syllogisms?
cf. the diagrams here
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How do complex propositions and Aristotle's logic work?
Is it allowed to create a syllogism with complex propositions?
Here is my example where P is a sequence of actions and M is a final cause.
S = "Cake maker"
P = "Finding of ingredients, ...
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Is this Barbara syllogism of a final cause right?
Hi i'm trying to learn how to make an explanation of a final cause in the form of a Barbara syllogism but I don't know if I have the terms in the right order.
The Barbara definition I'm using is from ...
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Which author(s) first talked of Aristotle's syllogistic as a logic of terms?
Which author(s) first talked of Aristotle's syllogistic as a logic of terms?
Thank you for any scholarly references.
Aristotle does defines the notion of "term" in Prior Analytics:
I call a ...
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Converting a Euclidian proposition to a syllogism format
I am attempting to analyze Euclid's proof demonstrating that the interior angles of a triangle are equal to two right angles (book 1, prop 32). In particular, I'm looking for a way to convert the ...
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Can one look at philosophy under the light of fictionalism? What ideas follow from this thought process? [closed]
I understand that fictionalism can be attributed to a majority of disciplines, the ones I am familiar with are modal fictionalism, mathematical fictionalism and moral fictionalism, so I was thinking ...
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Colored areas in categorical proposition Venn diagrams
This recent question prompted me to read about the square of opposition and I am confused about the purpose of red and white regions in Venn diagrams from this diagram. I think these Venn diagrams are ...
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Existential import in "No A is B"
I have doubts about the existential import in categorial propositions of the form "No A is B" under Aristotelian interpretation. In "No A is B", it is assumed that both A and B are ...
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Questions about categorial propositions
I have some doubts regarding categorial propositions used in syllogism.
Does "No A is B" implies "Some A is not B" and "Some B is not A"? Is there any counterexamples to ...
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Do you gain further truth from syllogisms
If you have a valid syllogism thats conclusion is true, have you gained any further truth?
I'll explain my reasoning.
The syllogism:
All men are mortal.
Socrates is a man
Conclusion: Socrates is a ...
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Does subalternation apply only to syllogistic logic, but not to other logic systems?
According to Copi's Introduction to Logic, in the square of opposition in Aristotle's Syllogistic Logic, there are four kinds of relationships between propositions:
contradictory: two propositions ...
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Do "No S is P" and "All S are not P" mean the same?
I am reading about categorical syllogism in Copi's Introduction to Logic. I was wondering what differences are between the following statements:
No S is P.
All S are not P.
Am I correct that
Their ...
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How did Aristotle discover his logic?
Supposedly Euclid employed analysis (conclusions→principles) and not synthesis (principles→conclusions) when he devised his definitions/postulates/axioms in his Elements.
How did Aristotle discover ...
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Does an argument require an explicit statement of conclusion?
The book I'm reading Critical Thinking by Brooke Noel Moore, Richard Parker says that the following is an argument.
John Montgomery has been the Eastern Baseball League’s best closer this
season. ...
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What is the name of "syllogisms" having conclusions with major and minor terms reversed? Can such "syllogisms" be valid?
It seems we can write a correct and incorrect version of any syllogistic form, depending on the order of the major and minor terms in the conclusion. Take, for example, AAA-4.
Correct version:
All P ...
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Chapter 22 in Organon, negative apodeictic term and problematic premise
Paragraph 4 in Chapter 22 in Prior Analytics of Aristotle:
For let us assume that A necessarily does not apply to C, and that B may apply to all C. Then by conversion of the affirmative premiss BC ...
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Does the free-logic-style semantics for traditional syllogisms imply that something exists?
I'm looking at Option 3 in Bumble's answer here which references this article on existential import in term logic in the Logic Museum website.
Does the free-logic-style semantics for term logic ...
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Possible vs may (or impossible vs cannot) in Aristotle's Prior Analytics
In chapter 13 of the Prior Analytics, it is written that "it is evident if it is possible for A to apply to B, it is also possible for it not to apply". Which naively speaking makes sense, ...
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Which practical applications of the fourth figure of syllogism exist?
There are four figures of simple categorical syllogism, well-known since Aristotles.
I started to wonder about practical applications of each figure, so I've addressed different literature, obtaining ...
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Logic reasoning problems books
Could you, please, recommend any books with a set of logic problems or exercises on deductive and inductive reasoning, syllogism.
Something that contains a set of questions, such as
It is known that ...
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What is the fallacy Carl Jung is alluding to in this passage?
What kind of fallacy did he mean?
We start, for instance with a perfectly reasonable assumption,
such as "NO UNREASONABLE BEING IS FREE" - in other words, has free will.
This is ...
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How can syllogisms with contradictory premises be valid?
A syllogism is valid if it is impossible for the premises to be true and at the same time the conclusion to be false.
Consider the following syllogism:
P1: This apple is red.
P2: This apple is not red....
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Is categorical logic the same as predicate logic
In philosophical logic, categorical logic is the logic that deals with the logical relationship between categorical statements. I wonder if categorical logic is considered the same as predicate logic (...
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How is the syllogism in my question called?
We all know the most famous syllogism introduced by Aristotle:
All men (people) are mortal. Socrates is a man. Therefore Socrates is mortal.
But what if we say:
All mortals are men (people). Alice ...
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Could someone please write this argument's form
"No rock is sentient. Some mammals are sentient. Hence, no mammal is a rock."
I wrote a form and it's apparently wrong, but I don't get how.
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Why bother with anything else besides Aristotle's syllogistic logic?
Disclaimer: this a "devil's advocate's question", meaning I know a lot of the answer, but for the sake of playing the Q&A game, I won't self-answer right away. The main reason I'm ...
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Does this argument disprove immaterialism?
-Every observation we have analysed has a material cause.
-By inductive reasoning, all observations have materialistic causes.
-Hence, there are no immaterial causes and immaterialism doesn't exist.
(...
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What are the differences between an argument and a syllogism?
What are the differences between an argument and a syllogism?
Along with definitions and usages, I would like examples to understand the differences.
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Structure of a deductive argument
I wonder if this is true for all deductive arguments,
a deductive argument must have at least one premise where the term
"ALL" or "NONE" or an equivalent word appears
Is it true? ...
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Non-equivalence of `i`-form and a claim of existence
What's the difference in meaning between an i-sentence and its corresponding existential claim?
In traditional logic, the following inference is valid
All As are Bs. AaB
----------------- --...
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Term Logic Paraconsistency -- Is it just a meta-level manifestation of existential import?
This lecture by Graham Priest contains an interesting claim, namely that term logic is paraconsistent.
I have two questions about this:
Is paraconsistency in this context ever considered a meta-level ...
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Question of Validity in syllogisms of deductive argument
I read the following excerpt from my A-Level Philosophy book:
"Two key terms that you need to understand in relation to deductions and other
forms of argument are ‘validity’ and ‘soundness’. ...
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How can we prove this argument is invalid?
Let's say below is the argument,
Premise 1: All men are mortal
Premise 2: Socrates is a man
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Conclusion: Therefore, Socrates can think
Now, to prove an ...
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What's wrong with this syllogism?
No one held for murder is given bail
Smith isn't held for murder
Hence Smith is given bail
no M is B
s is not M
s is B
What's wrong with the conclusion?
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What is it called when the conclusion of one syllogism is inserted as the minor premise of a second?
As an example in Lewis's "Mere Christianity," he argues for objective morality with:
Major: If you can judge one moral code (M1) to be better than another (M2) then objective morality exists.
Minor: ...
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Is this argument about the disjuncive syllogism valid and sound?
If some arguments of the form disjunctive syllogism have false premises, then some arguments with false premises are deductively valid. Some arguments of the form disjunctive syllogism have false ...
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Is this the correct way to phrase a logical argument with multiple syllogisms?
I'm not familiar with phrasing arguments in the form of traditional logical syllogisms, so I'd like to ask if this formulation is correct, or if it can be expressed more concisely. Note, I'm not ...
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What's the difference between "All A are B" and "A is B"?
I'm having trouble catching the difference between these two forms. I tried to draw some Venn diagrams but it's not helping.
"All A are B" means A is contained in B.
Does "A is B" mean A is also ...
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Why does the Principle of Explosion not make Mathematical Logic inconsistent? [closed]
Step Proposition Derivation
1 ------P --------- Assumption
2 ---- ¬P --------- Assumption
3 ----- P ∨ Q ----- Disjunction introduction (1)
4 ----- Q --------- Disjunctive syllogism (3,2)
https:...
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Problem with existential import in syllogisms (Barbara)
For a syllogism in Barbara, why is it the case that
All men are mortal.
James’ son is a man.
Therefore James’ son is mortal.
assumes that James has a son but in the case of saying
All ...
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How to solve this natural deduction problem?
This one is driving me crazy. I don't understand most keys for de morgan, modus ponens, etc, so please abbreviate if possible? EX: DM, MP, SIMP, HS, Conj, Imp (material Implication). Thank you anybody ...
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major/minor term of a syllogism when order of conclusion can be reversed
Consider:
All ‘A’s are ‘B’s
No ‘B’s are ‘C’s
Is it not the case that the conclusion to this could either be:
No ‘A’s are ‘C’s
or
No ‘C’s are ‘A’s
?
Is it not also the case that the minor term ...
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Why is there an O type conclusion in modus celaront
Modus celaront is type logical syllogism.
No reptiles have fur. (MeP)
All snakes are reptiles. (SaM)
∴ Some snakes have no fur. (SoP)
The conclusion is of a O type(Some .. are not ...). Why is ...
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Could the link between virtues and pleasures and pains in the third chapter of Nicomachean Ethics' book II be considered a hypothetical syllogism?
In the chapter 3 of Nicomachean Ethics' book II, Aristotle says:
Again, if the virtues are concerned with actions and passions,
and every passion and every action is accompanied by pleasure and
...
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Which logical fallacy is this: A is a C, B is a C, therefore A is a B?
Does this kind of logical fallacy have a name?
Apples are fruit.
Oranges are fruit.
Therefore, apples are oranges.
I'm guessing it's a particular kind of statistical syllogism?
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"Syllogisms which produce understanding"
I remember reading somewhere that the aim of Aristotle's Prior and Posterior analytics was to show which kinds of syllogisms produce understanding. I do not remember where I read this but I think it ...
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Do I have to use the BARBARA, CELARENT... etc?
My logic book is making me memorize the mnemonic that lists all these Latin names in order to remember valid syllogism forms, as well as how to reduce them into the first figure. My question is, do I ...
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Is this an example of Undistributed Middle?
Is this an example of Undistributed Middle?
John is not a teenager, since all teenagers are impulsive, and John is not impulsive.
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