Questions tagged [propositions]
The propositions tag has no usage guidance.
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Why is the statement false: If (A⊃B)∨(A⊃C) is true, then A implies either B or C
I'm reviewing my previous exams for the final, and the only two true or false questions that confuse me are:
If (A⊃B)∨(A⊃C) is true, then A implies either B or C.
(P⊃Q)∨(P⊃~Q) means P⊃(Q∨~Q).
The ...
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Intuitively, why are Universal Statements true in the Empty Universe?
Source: p 165. Sweet Reason: A Field Guide to Modern Logic (2010 2 ed) by Henle, Garfield, Tymoczko.
I read this on Math SE; please advise if it pertains to my simpler question.
One property of ...
user8572
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Why isn't "I am Bill" a proposition?
In fleshing out the traditional definition of omniscience, William Lane Craig distinguishes between propositional knowledge and non-propositional knowledge, claiming that to be omniscient is to know ...
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Can the material conditional be used in other situations?
Can the material conditional in classical logic (e.g. propositional logic or predicate logic like first-order logic) be used to reason about propositions that are not factual? E.g., using a ...
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can we know whether the self-referential statement: "It's not possible to deduce whether P1 is true or false" is undecidable?
Update: Simple concise version
Thanks to Nick R for pointing in the right direction.
The statement P0: "this statement is false" is undecidable.
The statement P1: "this statement is undecidable" is ...
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Does the existence of the proposition require language to be referential?
If we grant that there is a proposition wherein something meaningful is being asserted, does that require us to think of language as essentially representative in some way?
If language didn't contain ...
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What are factual propositions?
I've been reading up on epistemology, after having studied a bit of logic. Given that, I am in a good (or at least better) position to understand a proposition, and it's properties. One such property ...
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Truth Value of Sentences Containing Logical Contradictions
Do propositions containing logical contradictions have truth values, or are they meaningless? For example:
A) Some married bachelors exist.
B) 95% of married bachelors live in Maryland.
C) ...
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Wittgenstein and Picturing Relationships
I've been listening to BBC's "In Our Time" on Wittgenstein here, but I can't seem to understand why Wittgenstein thought that "a proposition can't picture the pictorial relationship." One of the ...
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How do you prove that this is a tautology?
((p->q) and (r->s) and (p or r)) -> (q or s)
How would you prove that this is a tautology? Using natural deduction?
My attempt on this question is the following.
Since a tautology means W entails ...
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Is what makes a proposition true only determined by its referent?
I was wondering if it is trivial that when the content of a belief can be given or "determined" by mind independent reality, the belief is "about" mind independent reality.
I think that the content ...
user6917
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What distinctions between Exclusive vs Exceptive Propositions have I overlooked?
Abbreviate 'Standard Form Categorical Propositions' to SFCP and 'Ordinary Statements' to OS.
Source: p 256-257, A Concise Introduction to Logic (12 Ed, 2014) by Patrick Hurley.
The textbook did not ...
user8572
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Would the absence of universals not make it impossible to make and/or express judgments?
Predication is an integral part of making a judgement, which is expressed in propositions (such as 'the sun is round'). Predication itself is possible because in some sense something can be said of ...
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Wittgenstein criticizes Coffey's work 'The Science of Logic' in its assumption that every proposition requires a subject and a predicate. Why?
Why does Wittgenstein believe there can be propositions that lack a subject or predicate? What examples does Wittgenstein give in support of this belief?
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If we assume that principles are the simplest propositions that can be said about an object, can they coherently be rejected?
An argument for some sort of 'principles' in the Aristotelian sense is as follows:
1.) If we can think something about something, we must be able to think at least the most simple of propositions ...
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