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

The admission officers at Punjab College's Summer Political Science Seminar are offering special financial aid packages to applicants from the area, which score above the 90 percentile in a local competition. Applicants from other areas who score above the 90 percentile in the national competition will also be offered the package. The officers want to make sure that the applicants who are offered packages are the top scorers.

Which one of the following statements would serve to undermine the admission officers' intent?

  1. The highest scoring applicants can also apply to other seminars and choose not to attend the Punjab College's seminar.

  2. Competitions can be biased and therefore are the unfair measures of an applicant's potential performance.

  3. Those applicants scoring above the 90 percentile in the competition might be able to afford to attend the seminar without the financial aid package.

  4. Some of the applicants offered the financial aid package might have lower scores in the competition than some who are not offered packages.

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The admission officers want to offer the overall highest scorers the package, yet they are basing the scores on a national and local test. It is possible that the top 10 percent of the local people are not nearly as successful at the competition as the top half of the national people. But, the best among locals, who are not, in this instance, the top scorers, would still be offered the package.

Multiple choice

A food product is considered nutritious if it meets two criteria. It must meet some BIS standard for fat content and it must not contribute to a vitamin deficiency. For instance, ice cream, which contains milk, does not contribute to a vitamin deficiency, but it does not meet BIS standards for fat content. Therefore, ice cream is not a nutritious food.

If all of the above statements are true, each of the following must also be true EXCEPT

  1. not contributing to a vitamin deficiency must be a criterion met by a nutritious food.

  2. manufacturers of ice cream are not concerned with the nutritional value of their product.

  3. ice cream contains nothing that would be a detrimental to vitamin intake.

  4. some foods that contain milk are not nutritious.

  5. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

From the argument it is impossible to tell whether ice cream manufacturers are concerned with the nutritional value of their product.

Multiple choice

Resolution produces proofs by

  1. refutation

  2. matching

  3. substitution

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

Resolution is a rule of inference used in automated theorem proving that works by showing that the negation of the goal leads to a contradiction, thus proving the goal by refutation.

Multiple choice

Knowledge level describes

  1. information

  2. facts

  3. rules

  4. values
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The knowledge level, as defined by Allen Newell, is the level of abstraction where we describe a system in terms of its knowledge (facts) and goals, independent of how that knowledge is implemented.

Multiple choice

In forward reasoning, search proceeds from

  1. the goal states

  2. the start states

  3. the problem states

  4. the intermediate states
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Forward reasoning (or data-driven reasoning) starts from the known facts (the start state) and applies rules to derive new facts until the goal state is reached.

Multiple choice

In procedural representation, logical assertions are viewed as

  1. data

  2. program

  3. both (1) and (2)

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In procedural representation, knowledge is encoded as a set of instructions or procedures to be executed. Therefore, logical assertions are viewed as programs that perform actions to solve problems.

Multiple choice

Predicate logic is the way of representing

  1. knowledge

  2. data

  3. facts

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

Predicate logic is a formal system used to represent facts and relationships between objects in a domain. It allows for the expression of complex statements about entities and their properties.

Multiple choice

Research shows that people aged 30-50 yrs are more inclined to buy computer and video games as compared to youngsters or children, who are widely perceived to be much fonder of such entertainment media. The popular belief about the youngsters and children must be, therefore, discarded.

The argument presented above suffers from the major fallacy of

  1. not giving any information about people older than 50

  2. discussing only one item of purchase made by older people

  3. failing to differentiate between a buyer and an end-user

  4. talking about only games rather than books and magazines

  5. relating purchase behavior to specific age groups
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The discrepancy can be explained only in terms of a distinction between a buyer and an end-user. Every buyer of a commodity is definitely not its end- user. Adults, perhaps parents, might be buying these for their children.

Multiple choice

V.X. Ivan must be a charming man. This is his third marriage and each time he marries an heiress.

Which of the following can be most correctly stated about the above claim?

  1. The claim is based on the similarity between two or more events.

  2. The claim suffers from the fallacy of ambiguity.

  3. The claim is made valid only by an underlying assumption.

  4. The claim makes mockery of the laws of monogamy.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

There is no evidence to prove Ivan is a charming man, it's an assumption. Only the fact of the assumption that “anyone who has been married thrice must be charming” makes this claim valid.

Multiple choice

That which cannot be avoided.

  1. Inevitable

  2. Irreparable

  3. Incomparable

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

Inevitable means certain to happen; unavoidable. Irreparable means impossible to rectify or repair.