Structure of Arguments Questions and Answers

Answer: A

The correct diagram is (A): three circles in a row, the middle one overlapping both outer ones.

Let the middle circle be Students. Some boys are students and some are not, so the Boys circle overlaps Students without lying inside it; the same holds for Girls. No one is both a boy and a girl, so the Boys and Girls circles do not touch. That is exactly diagram (A).

Diagram (B) would put all boys and all girls inside Students, which is too strong. (C) nests the three sets inside one another, and (D) makes the two inner sets overlap, which would mean some boys are girls.

Answer: B

The logical order is 2-4-1-5-3: Population, Unemployment, Poverty, Disease, Death.

The chain runs from cause to effect. A growing population outstrips the jobs available, causing unemployment. Without income, people fall into poverty. Poverty brings malnutrition and poor sanitation, and so disease, and untreated disease ends in death.

The other orders break the causal chain: one puts unemployment before population, one starts with poverty and puts population in the middle, and one starts with disease.

Answer: B

The correct diagram is (B).

All mothers are women, so the Mothers circle lies wholly inside the Women circle. Some athletes are women and some are not, and some athletes are mothers and some are not, so the Athletes circle must overlap both the Women circle and the Mothers circle inside it. Diagram (B) shows a small circle inside a larger one, with a third circle cutting across both.

(A) shows Athletes linking two separate overlapping groups, with no subset relation. (C) puts all three inside each other, making every mother an athlete. (D) puts two overlapping groups inside a third, which would make all athletes women.

Answer: B

An argument offers reasons (premises) to support a conclusion. Assertion I gives a reason, that thieves cannot go to heaven, for the conclusion that you should keep your wealth in heaven, so it is an argument. Assertion II states the difference of skin colour of beings and gives its cause, the distance from the sun and the body's reaction to the sun; it explains a fact, it does not try to prove a conclusion. So the first assertion is an argument and the second is not. The answer is that the assertion-I is an argument but the assertion-II is not.

Answer: C

The expressions 'first President of India', 'author of Godan', 'books in my library', 'blue things' and 'students who work hard' are all descriptive phrases. Each describes a thing or a class by a property or a relation instead of naming it, so each is classed as a description. Common names are single words for classes, like 'book', and proper names are names of individuals, like 'Rajendra Prasad', and neither fits phrases of this kind. The key does not use the option of an indefinite description. The answer is descriptive phrases.

Answer: D

The statement 'Nothing is larger than itself' says that no thing stands in the relation 'is larger than' to itself, and a relation of which that is true for every object is called irreflexive. The relation is also asymmetrical and transitive, but the statement only expresses the first of these. It is not intransitive, since larger than is transitive, and antisymmetric is a condition on pairs of different things which is not what the expression says. The answer is irreflexive.

Answer: A

The key marks the first option, that (A) is true, (R) is doubtful and (R) is not the correct explanation of (A). The assertion states a fact about the number of laws and crimes today, which may be accepted. The reason says that to reduce crime we must eliminate the laws, which is a doubtful claim, and in any case it does not explain why there are more laws and more crimes, since it is a remedy and not a cause. The options that call the assertion false or doubtful, or the reason true and explanatory, do not agree with the key. The answer is the first option.

Answer: B

The definition of abortion as the ruthless murdering of innocent beings is a persuasive definition. It uses words with a strong emotional charge, ruthless, murdering and innocent, to move the hearer to a particular attitude, and it does not simply report the meaning of the word. A lexical definition reports the standard usage in a dictionary, a stipulative definition assigns a new meaning to a term for a purpose, and a theoretical definition gives a scientific or theoretical account of the thing. The answer is persuasive.

Answer: B

An argument is a group of statements in which some, the premises, are offered as support for another, the conclusion, and it is shown by words such as so, since and therefore. Options A, C and D each give a premise with a conclusion drawn from it by 'so' or 'since'. Option B is a single conditional statement, 'if he is growing fat and does not eat during the day, he will be eating at night', which asserts a link between its parts but does not offer one as the ground for the other, so it is not an argument. The answer is the conditional statement in option B.

Answer: A

A Venn diagram is a way of representing the classes of a syllogism by overlapping circles, and it is used both to represent a syllogistic form and to assess its validity: if shading the premises also shades or marks the conclusion, the form is valid. So the first option is right. A Venn diagram is about validity and not truth, because the truth of the premises depends on facts that no diagram can show, and so the options referring to the truth of inferences are wrong. The option that it represents but cannot assess validity is also wrong. The answer is that it represents and assesses the validity of elementary inferences of syllogistic form.