Questions tagged [logic]
Use this tag for general questions about logic that are not categorizable under some more specific tag, like "mathematical logic", "informal logic", "classical logic", etc.
4,244 questions
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Does math admit (care about) the existence of an entity?
Philosophers always concern about the existence of entities. For example, they discuss the propositions like "The bird exists." or "Unicorn does not exist". But in math, ...
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Should an ad hoc modification of a theory be rejected? [closed]
Suppose someone has theory X which proposes to explain datum {A, B, C, D}
Now the theory has an “all-or-nothing” stance, if X doesn’t explain A then it doesn’t explain the rest.
Suppose now that A in-...
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How Knowledge Claims and Logic Presuppose God [duplicate]
P1: Logic is objective.
P2: Since it is objective, it has existence in reality, otherwise logic doesn't exist and so contradictions can exist in reality. Laws of logic are not physical or contingent ...
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Is the statement “Nothing is perfect” self-contradictory because it implies perfection through imperfection?
The common saying is that “Nothing is perfect.” But if everything in the universe is imperfect, then imperfection itself applies universally without exception. In that case, imperfection is consistent ...
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Why does first-order Peano Arithmetic need induction at all?
Here is the signature of Peano Arithmetic:
{Z (0), S (1), P (2), T (2)}
I will use capital letters to focus on logic as formal manipulation of strings of symbols. N stands for ¬, A for ∀, I for →, E ...
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Condition in disjunct, is this an exclusive or inclusive disjunction?
"You've got to do one of two things when you've got to keep people happy: either, give them something that will satisfy them, better food, better clothes, better homes; or if you can't do that, ...
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is the following argument valid?
Premise 1 : if the consequent of premise 1 is true , then the antecedent of premise 1 is true
Premise 2 : the antecedent of premise 1 is true
Therefore,
Conclusion : the consequent of premise 1 is ...
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How would you formalise the sentence "I am a liar" in first order logic?
How would you formalise the sentence "I am a liar" in first order logic?
ChatGPT can't do that, what seems to be the problem?
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is the duality law referring to contraposition?
Is the duality law referring to contraposition?
I ask because of the following:
According to Wolfram MathWorld, the duality law is as follows: A metatheorem stating that every theorem on partially ...
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How come you don’t use DeMorgan’s Laws on Statements with Generalized Quantifiers
How come you don’t use DeMorgan’s Laws on statements with generalized quantifiers? For more information as to what a generalized quantifier is, see the following link: https://plato.stanford.edu/...
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Some humans are not horses
From https://en.wikipedia.org/wiki/Syllogism
Camestros (AEO-2)
Similar: Calemos (AEO-4)
All horses have hooves. (PaM)
No humans have hooves. (SeM)
∴ Some humans are not horses. (SoP)
While that's ...
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Too logical to be true? [closed]
This is not a repetition of my last question; it's not about specific conditions, but about the cause for the non-transferability of φ as such.
However, the premises for the questions are the same, ...
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Does using Meinongian Logic simplify Mathematical Proofs? [closed]
Does using Meinongian Logic simplify Mathematical Proofs? I ask because it does seem to simplify mathematical proofs. Especially when existence is treated as a predicate. To show what I mean consider ...
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Is an idea stronger with many reasoning chains or only one solid chain?
I wonder if a conclusion or idea becomes more robust when it is supported by many different reasoning chains, or if only one strong chain is enough.
For example, in daily life when I want to decide if ...
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Is falsifying an inductive hypothesis an example of modus tollens?
Is falsifying an inductive hypothesis an example of modus tollens?
To illustrate what I mean consider the following: We observe some swans are white. And by induction we make the hypothesis that given ...
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