All Questions
Tagged with symbolic-logic propositions
4
questions
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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 ...
- 1,191
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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,...
- 63
3
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What are the rules for a zero-premise derivation involving disjunctions?
I'm having trouble with the following zero-premise deduction that involves two disjunctions:
The solution seems simple, but I'm unsure of how to proceed with the two disjunctions. If it were just ...
4
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Implication Introduction formulated as a theorem?
While making a list of the rules of inference for my math students, I came across this list on Wikipedia:
I noticed a pattern: for every introduction rule, there seems to be an elimination rule, and ...
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