All Questions
Tagged with propositions logic
43
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Is there any self-contradiction in this statement that "everything is beautiful"?
'Everything is beautiful.'
If you deny the proposition of 1), it is 'something is not beautiful'.
The proposition 'something is not beautiful', which comes from 2), is included in 'everything'.
In ...
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How should an argument containing an exceptive proposition be tested?
IX. Exceptive Propositions in 7.3 Translating Categorical Propositions into Standard Form in Copi's Introduction to Logic says:
Because exceptive propositions are not categorical propositions but
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3
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Truth-functional vs non-truth functional conditionals
I'm struggling to understand truth functionality.
I know that a connective is truth-functional if the truth value of a compound statement formed with that connective is completely determined by the ...
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Universal affirmative propositions and the similarity of individual objects?
I'm trying to understand what counts objects as being members of a class. I'm getting stuck when there are variations for each object of a class but they might still be said to be part of that class.
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Is division of propositions by their modality comprehensive?
I call division of any concept comprehensive if the combination of concepts received by such division has a scope congruent (containing exactly the same objects) to the scope of the divided concept.
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What context do quantifiers make valid expressions?
Say I have a formal language such that x is an individual constant and symbolically has a particular value (say 2) a proposition such as x+1=3 already has the value of true, and I cannot define a ...
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Do all true statements express the same proposition?
Do all true statements express the same proposition? I know that, for example, the statements "2=2" and "1+1>1" are distinct sequences of symbols. However, I want to know, do ...
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Are contradictory propositions in the propositional logic still contradictory in the predicate logic?
There is one seeming issue I happened upon that bothers me to no end.
Take a proposition like “Snow is white”. “Snow is white” and its negation “Snow is not white” are obviously contradictory. However,...
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What is my fallacy? LSAT Reasoning Question: Titanium Ink
I have a question regarding an LSAT Reasoning question and it drives me crazy
Question is:
Until recently it was thought that ink used before the sixteenth century did not
contain titanium. However, ...
user49145
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When is a wish not a proposition?
Consider these sentences:
S1. Would that Los Angeles were not that far away.
S2. I really wish Los Angeles were nearer to New York.
S3. I wish that Los Angeles were not that far away.
S4. It is going ...
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Can the word "probably" be used in a proposition? (logic)
I'm interested in applying logic to day-to-day reasoning. The problem is that formal logic seems really restrictive to limit inductive arguments to be only universal ("all swans are white"). Few ...
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Confused about the answers to two logic problems
True or False? If monkeys can fly, then 1 + 1 = 3.
What is logically equivalent to all x (p(x) + ~q(x))?
For the first one I think it is False.
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How to make the statement "If A or B then C" More Rigorous?
Suppose that I say the following,
If A or B then C
It is clear what happens if only A is true, if only B is true, or if neither A nor B are true.
However, what happens if both A & B are true? ...
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How did Aristotelian logic view this?
I am very interested in the logical aspect of Aristotelian philosophy, especially how it was used by al Farabi and Ibn Sina in explaining understanding and breaking this complicated process down ...
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If logical propositions aren't tautologies (a la Wittgenstein), then what could they be?
This is a historical question about philosophical views. I believe I understand the claim made by Wittgenstein and others that logical propositions are tautologies. I'd like to know what other views ...
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