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

Which of the following is a sufficient condition for a deductive argument to be sound?

  1. The premises must be true.

  2. The conclusion must be true.

  3. The premises must be relevant to the conclusion.

  4. The argument must be in a standard logical form.
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

A deductive argument is sound if it is both valid and has true premises. This means that the argument must have a structure that guarantees the conclusion follows from the premises, and the premises must accurately represent the facts of the situation.

Multiple choice

Which of the following is not a type of valid inference recognized in Nyaya logic?

  1. Kevalavyatireki (simple negative inference)

  2. Anvayavyatireki (conjunctive inference)

  3. Savyabhichara (inconclusive inference)

  4. Rupakarana (hypothetical inference)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Savyabhichara, or inconclusive inference, is not a type of valid inference recognized in Nyaya logic.

Multiple choice

Which of these is NOT a type of fallacy identified by the Nyaya school?

  1. Affirming the Consequent

  2. Denying the Antecedent

  3. Appeal to Ignorance

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

Ad Hominem, which involves attacking the person making an argument rather than the argument itself, is not a fallacy specifically identified by the Nyaya school.

Multiple choice

In a hypothesis testing scenario, what is the null hypothesis?

  1. The hypothesis that is being tested

  2. The hypothesis that is assumed to be true

  3. The hypothesis that is rejected

  4. The hypothesis that is accepted
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The null hypothesis is the statement that is assumed to be true until there is evidence to reject it.

Multiple choice

Which of the following is a valid formula in Second-Order Logic?

  1. ∃x∀yP(x, y)

  2. ∀x∃yP(x, y)

  3. ∃x∀y∃zP(x, y, z)

  4. ∀x∃y∀zP(x, y, z)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In Second-Order Logic, a valid formula is one that is true in all interpretations. The formula ∀x∃yP(x, y) is valid because for any interpretation, there exists a y such that P(x, y) is true for all x.

Multiple choice

Which of the following is a decidable fragment of Second-Order Logic?

  1. Monadic Second-Order Logic

  2. Second-Order Logic with Equality

  3. Second-Order Logic with Transitive Closure

  4. Second-Order Logic with Counting
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Monadic Second-Order Logic is a decidable fragment of Second-Order Logic.

Multiple choice

Which of the following is a decidable fragment of second-order logic?

  1. Monadic second-order logic

  2. Second-order logic with equality

  3. Second-order logic with transitive closure

  4. Second-order logic with counting
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Monadic second-order logic is a decidable fragment of second-order logic.

Multiple choice

In a syllogism, the conclusion is:

  1. A statement that follows logically from the premises.

  2. A statement that is unrelated to the premises.

  3. A statement that contradicts the premises.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a syllogism, the conclusion is a statement that is derived from the premises using the rules of logical inference.

Multiple choice

In a categorical proposition, the predicate term refers to:

  1. The category of things that the proposition is about.

  2. The property or characteristic that is being attributed to the subject term.

  3. The relationship between the subject term and the property or characteristic.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a categorical proposition, the predicate term refers to the property or characteristic that is being attributed to the subject term.

Multiple choice

Which of the following is an example of a universal negative proposition?

  1. All dogs are mammals.

  2. Some birds can fly.

  3. No cats are fish.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A universal negative proposition is a statement that denies that any members of a category have a certain property. In the example given, the statement "No cats are fish" denies that any members of the category of cats have the property of being fish.

Multiple choice

In a syllogism, the major premise is:

  1. The premise that contains the major term.

  2. The premise that contains the minor term.

  3. The premise that contains the middle term.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a syllogism, the major premise is the premise that contains the major term, which is the term that appears in the conclusion.

Multiple choice

In a syllogism, the minor premise is:

  1. The premise that contains the major term.

  2. The premise that contains the minor term.

  3. The premise that contains the middle term.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a syllogism, the minor premise is the premise that contains the minor term, which is the term that appears in the conclusion.

Multiple choice

In a syllogism, the middle term is:

  1. The term that appears in both premises but not in the conclusion.

  2. The term that appears in the conclusion but not in either premise.

  3. The term that appears in both premises and the conclusion.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a syllogism, the middle term is the term that appears in both premises but not in the conclusion.

Multiple choice

Which of the following is an example of a valid syllogism?

  1. All men are mortal. Socrates is a man. Therefore, Socrates is mortal.

  2. All dogs are mammals. Some mammals are carnivores. Therefore, all dogs are carnivores.

  3. Some birds can fly. All eagles are birds. Therefore, all eagles can fly.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A valid syllogism is a syllogism in which the conclusion follows logically from the premises. In the example given, the conclusion "Socrates is mortal" follows logically from the premises "All men are mortal" and "Socrates is a man".

Multiple choice

Which of the following is an example of an adversative transition?

  1. But

  2. Therefore

  3. So

  4. As a result
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

But is an example of an adversative transition, which is used to contrast two ideas.