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

Multiple choice

Which of the following is an example of a deontic fallacy?

  1. The fallacy of appeal to emotion

  2. The fallacy of affirming the consequent

  3. The fallacy of denying the antecedent

  4. The fallacy of composition
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The fallacy of affirming the consequent is a deontic fallacy that occurs when someone assumes that because a certain action is permitted, it is also obligatory.

Multiple choice

Which of the following is a type of modal logic?

  1. Alethic modal logic

  2. Deontic modal logic

  3. Epistemic modal logic

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

Alethic modal logic deals with the concept of truth and necessity, deontic modal logic deals with the concept of obligation and permission, and epistemic modal logic deals with the concept of knowledge and belief.

Multiple choice

In modal logic, what is a possible world?

  1. A world that is consistent with the laws of logic

  2. A world that is consistent with the laws of nature

  3. A world that is consistent with the laws of morality

  4. A world that is consistent with the laws of mathematics
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A possible world is a world that is consistent with the laws of logic. This means that the laws of logic are true in all possible worlds.

Multiple choice

Which of the following is a valid logical argument?

  1. All men are mortal.

  2. Socrates is a man.

  3. Therefore, Socrates is mortal.
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

This is a valid syllogism, where the conclusion follows logically from the premises.

Multiple choice

Which of the following is an example of a proposition?

  1. Socrates is a man.

  2. All men are mortal.

  3. The sky is blue.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A proposition is a statement that is either true or false. The statement "The sky is blue" is a proposition because it can be either true or false.

Multiple choice

What is the law of non-contradiction?

  1. A thing cannot be both itself and something else at the same time.

  2. Nothing can come from nothing.

  3. The whole is greater than the sum of its parts.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The law of non-contradiction states that a thing cannot be both itself and something else at the same time. This means that a thing cannot be both true and false at the same time.

Multiple choice

What is the law of the excluded middle?

  1. A thing is either true or false.

  2. Nothing can come from nothing.

  3. The whole is greater than the sum of its parts.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The law of the excluded middle states that a thing is either true or false. This means that there is no third option.

Multiple choice

Which of the following is NOT a type of scientific explanation?

  1. Deductive explanation

  2. Inductive explanation

  3. Teleological explanation

  4. Mechanistic explanation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Teleological explanations are not scientific explanations because they appeal to purpose or final causes. Scientific explanations must be based on natural causes.

Multiple choice

Which of the following is NOT a type of scientific reasoning?

  1. Deductive reasoning

  2. Inductive reasoning

  3. Abductive reasoning

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

Analogical reasoning is not a type of scientific reasoning. It is a type of reasoning that involves drawing a comparison between two things.

Multiple choice

Which of the following is a central concept in modal logic?

  1. Possible worlds

  2. Syllogisms

  3. Categorical propositions

  4. Natural deduction
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Modal logic is a system of logic that deals with the concepts of possibility and necessity. Possible worlds are a key concept in modal logic, as they are used to represent the different ways that the world could be.

Multiple choice

Which of the following is an example of a modal proposition?

  1. All men are mortal

  2. It is possible that the moon is made of cheese

  3. 2 + 2 = 4

  4. Socrates is a philosopher
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A modal proposition is a proposition that contains a modal operator, such as 'possible', 'necessary', or 'impossible'. The proposition 'It is possible that the moon is made of cheese' is a modal proposition because it contains the modal operator 'possible'.

Multiple choice

Which of the following is a type of modal logic?

  1. Alethic modal logic

  2. Deontic modal logic

  3. Epistemic modal logic

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

There are three main types of modal logic: alethic modal logic, deontic modal logic, and epistemic modal logic. Alethic modal logic deals with the concepts of possibility and necessity, deontic modal logic deals with the concepts of obligation and permission, and epistemic modal logic deals with the concepts of knowledge and belief.

Multiple choice

Which of the following is a famous modal fallacy?

  1. The fallacy of affirming the consequent

  2. The fallacy of denying the antecedent

  3. The fallacy of modal transposition

  4. The fallacy of modal syllogism
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The fallacy of modal transposition is a modal fallacy that occurs when a modal operator is moved from one proposition to another in an invalid way. For example, the argument 'It is possible that Socrates is a philosopher, therefore it is necessary that Socrates is a philosopher' is a fallacy of modal transposition.

Multiple choice

What is the Münchhausen trilemma?

  1. A logical argument that shows that all attempts to justify our beliefs must ultimately rely on circular reasoning, infinite regress, or an unjustified assumption.

  2. A logical argument that shows that all attempts to justify our beliefs must ultimately rely on evidence, reason, or testimony.

  3. A logical argument that shows that all attempts to justify our beliefs must ultimately rely on intuition, faith, or revelation.

  4. None of the above.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Münchhausen trilemma is a logical argument that shows that all attempts to justify our beliefs must ultimately rely on circular reasoning, infinite regress, or an unjustified assumption.

Multiple choice

Which of the following is a key concept in Charles Sanders Peirce's pragmatism?

  1. Abduction

  2. Deduction

  3. Induction

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

Abduction is a key concept in Charles Sanders Peirce's pragmatism. It is the process of forming a hypothesis based on limited evidence.