Reasoning

Logic and Fallacies

1,716 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

Multiple choice

What is the fallacy of denying the antecedent?

  1. If P, then Q. Not P. Therefore, not Q.

  2. If P, then Q. Q. Therefore, P.

  3. If P, then Q. Not Q. Therefore, P.

  4. If P, then Q. P. Therefore, Q.
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

The fallacy of denying the antecedent is the logical fallacy of concluding P from not Q and the conditional proposition "If P, then Q".

Multiple choice

What is the method of truth tables?

  1. A method for determining the truth value of a compound proposition based on the truth values of its component propositions.

  2. A method for determining the validity of an argument based on the truth values of its premises and conclusion.

  3. A method for constructing a proof for a proposition.

  4. A method for finding the truth value of a proposition based on its logical form.
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

The method of truth tables is a method for determining the truth value of a compound proposition based on the truth values of its component propositions.

Multiple choice

What is the principle of explosion?

  1. If a proposition is false, then any proposition can be derived from it.

  2. If a proposition is true, then any proposition can be derived from it.

  3. If a proposition is true, then its negation can be derived from it.

  4. If a proposition is false, then its negation can be derived from it.
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

The principle of explosion is the logical principle that if a proposition is false, then any proposition can be derived from it.

Multiple choice

What is the term for the logical fallacy in which a conclusion is drawn from a premise that is not supported by evidence?

  1. Ad hominem

  2. Begging the question

  3. False dichotomy

  4. Non sequitur

  5. Straw man
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Non sequitur is the logical fallacy in which a conclusion is drawn from a premise that is not supported by evidence. The term literally means "it does not follow" in Latin.

Multiple choice

What is the term for the type of inference in which the conclusion is necessarily true if the premises are true?

  1. Deductive inference

  2. Inductive inference

  3. Abductive inference

  4. Analogical inference

  5. Hypothetical inference
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Deductive inference is the type of inference in which the conclusion is necessarily true if the premises are true. In other words, the conclusion is guaranteed to be true if the premises are true.

Multiple choice

According to the Verification Theory of Truth, a statement is considered true if:

  1. It can be verified through empirical observation.

  2. It is consistent with other accepted beliefs.

  3. It is supported by logical reasoning.

  4. It is universally accepted by all people.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Verification Theory of Truth emphasizes the importance of empirical verification as the criterion for truth.

Multiple choice

Which of the following statements is an example of a verifiable statement according to the Verification Theory of Truth?

  1. The sky is blue.

  2. God exists.

  3. Beauty is in the eye of the beholder.

  4. All humans are mortal.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The statement 'The sky is blue' can be verified through empirical observation, making it a verifiable statement.

Multiple choice

Which of the following statements is an example of a statement that is verifiable in principle but not verifiable in practice?

  1. The sun will rise tomorrow.

  2. There is life on other planets.

  3. All humans are mortal.

  4. Beauty is in the eye of the beholder.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The statement 'There is life on other planets' can be verified in principle through empirical observation, but it is not currently verifiable in practice due to technological limitations.

Multiple choice

The concept of aporia in ancient Greek philosophy refers to:

  1. A logical impasse

  2. A paradox

  3. An unanswerable question

  4. A state of doubt
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A Correct answer
Explanation

Aporia is a Greek term that refers to a logical impasse or a situation where there is no clear way to proceed. It is often used in philosophy to describe situations where there are conflicting arguments or evidence, leading to uncertainty or doubt.

Multiple choice

Which of the following is an example of epistemic authority?

  1. A doctor.

  2. A judge.

  3. A politician.

  4. A journalist.
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A Correct answer
Explanation

A doctor is an example of epistemic authority because they have knowledge and expertise in the field of medicine.

Multiple choice

Which of the following is NOT a principle of Formalism?

  1. Unity

  2. Variety

  3. Balance

  4. Representation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Representation, which refers to the depiction of objects, people, or events in a realistic or recognizable manner, is not a principle of Formalism.

Multiple choice

What is Bayes' theorem?

  1. A theorem that relates conditional probabilities

  2. A theorem that relates probability distributions

  3. A theorem that relates random variables

  4. A theorem that relates expected values
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bayes' theorem is a theorem that relates conditional probabilities and is used to update beliefs in light of new evidence.

Multiple choice

Which of the following is a characteristic feature of non-classical logic systems?

  1. The law of excluded middle always holds.

  2. The law of non-contradiction always holds.

  3. Logical connectives may have different truth tables.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In non-classical logic systems, the truth tables for logical connectives may differ from those in classical logic, allowing for a wider range of logical possibilities.

Multiple choice

In propositional non-classical logic, which of the following is a common type of connective?

  1. Negation

  2. Conjunction

  3. Disjunction

  4. Implication
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Implication is a common type of connective in propositional non-classical logic, and its truth table can vary depending on the specific non-classical logic system.

Multiple choice

Which non-classical logic system is known for its focus on possibility and necessity?

  1. Modal Logic

  2. Fuzzy Logic

  3. Intuitionistic Logic

  4. Paraconsistent Logic
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Modal Logic is a non-classical logic system that introduces operators for possibility and necessity, allowing for reasoning about what is possible or necessary in a given situation.