Reasoning
Logic and Fallacies
1,803 Questions
Understand the fundamentals of propositional logic, logical inference rules, and paradoxes. This set includes identifying logical fallacies, including those found in classical Nyaya logic. Strong grasp of these concepts is crucial for scoring well in the reasoning sections of competitive tests.
Propositional logic modelsLogical inference rulesTypes of logical fallaciesParadoxes and contingent truthsNyaya logic concepts
Logic and Fallacies Questions
What is the name of the epistemic logic rule of inference that allows us to infer knowledge of a disjunction from knowledge of one of its disjuncts?
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Conjunction Rule
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Disjunction Rule
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Modus Ponens
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Modus Tollens
B
Correct answer
Explanation
The epistemic logic rule of inference that allows us to infer knowledge of a disjunction from knowledge of one of its disjuncts is called the Disjunction Rule. It is expressed as follows: If Kφ or Kψ, then K(φ∨ψ).
Which of the following is an example of an epistemic closure principle?
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If you know that A, then you know that A or B.
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If you know that A, then you know that not A.
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If you know that A, then you know that A implies B.
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If you know that A, then you know that B implies A.
C
Correct answer
Explanation
An epistemic closure principle is a principle that states that if you know a proposition, then you also know all of its logical consequences. The principle 'If you know that A, then you know that A implies B' is an example of an epistemic closure principle.
Which of the following is an example of a violation of epistemic closure?
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You know that all bachelors are unmarried, but you do not know that all unmarried men are bachelors.
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You know that all dogs are mammals, but you do not know that all mammals are dogs.
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You know that all cats are animals, but you do not know that all animals are cats.
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You know that all humans are mortal, but you do not know that all mortals are humans.
A
Correct answer
Explanation
A violation of epistemic closure occurs when you know a proposition but do not know one of its logical consequences. The example 'You know that all bachelors are unmarried, but you do not know that all unmarried men are bachelors' is an example of a violation of epistemic closure.