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What is Syllogism?

The word syllogism is derived from the Greek word “syllogismos” which means “conclusion,
inference”. Syllogisms are a logical argument of statements using deductive reasoning to arrive at a
conclusion. The major contribution to the filed of syllogisms is attributed to Aristotle.

To know more about Govt Exams, check at the linked article.

The questions which are asked in this section contain two or more statements, and two or more
conclusions follow these statements. One has to find out which of these conclusions logically follow
the given statements. The statements have to be taken true even if they seem to be at variance from
the commonly known facts.

There are many ways of solving questions of syllogisms. The most effective and efficient method of
all is using a Venn diagram. Based on the given statements, one should draw all the possible
diagrams and then solve each of these diagrams separately. Finally, the answer common to all the
diagrams is taken as the correct one.

Statements of syllogisms

The questions of syllogisms of three main parts.

1. Major premise
2. Minor premise
3. Conclusion
The central premise is a statement in general, believed to be true by the author.

Example: All women are smart.

The minor premise is a specific example of the major premise.

Example: Amanda is a woman.

The conclusion is a specific statement which logically follows both major and minor statement.

Example: Amanda is smart.

Application of Venn diagrams

To identify whether the given conclusion is correct or not draw the Venn diagrams according to major
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and minor statements.

Statements of syllogisms

The questions of syllogisms of three main parts.

Note: The conclusion should be true according to all the possible cases. One should draw all possible
cases before arriving at a conclusion. Below the table that provides that correct combination of Venn
diagrams of major and minor premises.

Steps to solve syllogism questions:

1. Note the number of variables present in the given statements

Ex: Man, doctor, pilot, etc.

1. Draw a Venn diagram corresponding to each variable; several Venn diagrams is equal to the
number of variables.
2. Deduce the logical level by reading the statements and draw the corresponding Venn
diagram
3. Check the conclusions given by comparing it with the Venn diagram obtained
4. Select the correct conclusion.
The following table gives the correct representation of Venn diagrams applying the above rules.
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Solved examples:

Type 1 questions of syllogisms

Instructions: Observe the following statements and select if the conclusion is

Correct/ Incorrect

Example 1:

Major premise: All Actors are right-handed.

Minor premise: All right-handed are Artists.

The conclusion is: Some Artists are Actors.

A. Correct

B. Incorrect

Solution:

Explanation:

Case 1:

The Venn diagram of actors is inside right-handed and which in turn is inside the Venn
of artists. According to the diagram, the portion of the red Venn diagram overlapping
with green indicates that some actors artist are actors. Hence the conclusion is correct
according to this diagram, but can not be concluded as the final answer until the second
case is checked.

Case 2: Since all the Venn diagrams are overlapping with each other, according to the
diagram all the artists are actors or all the actors are artists. Hence the conclusion is “
some artists are actors” is wrong. Since the conclusion is wrong according to the
second Venn diagram. The correct answer will be option B incorrect.
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Instructions: Observe the following premises and select if the conclusion is

Correct/ Incorrect

Example 2:

Major premise: No pencil is cloth.

Minor premise: No sweaters are pencils.

The conclusion is: All sweaters are cloth

A. Correct

B. Incorrect

Solution:

Explanation:

In this case, as can be seen, there are three possible scenarios.

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Since “ No pencil is cloth” The diagram of pencil and cloth do not have any overlapping.
Hence, they are just touching each other( the diagram can also be represented by
keeping them apart, but that will not affect the logical conclusion). According to the
minor premise, since no sweaters are pencils, the diagrams of sweaters and pencil do
not overlap.

Case 1: If no sweaters are pencil, one possibility is there can be no sweater which is no
cloth also.

Case 2: There can be a sweater which is also cloth. Hence a part of sweater and cloth
overlap with each other.

Case 3: All clothes can be a sweater, as there is not any promise which says this
combination is not possible.

The conclusion “all sweaters are cloths” is correct only according to 3rd case but not
with respect to the 1st and 2nd case. Hence the conclusion is incorrect.
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For questions from the various other topics under the reasoning ability section,
candidates can visit the Logical Reasoning Questions page.

Type 2 questions of syllogisms.

Observe the following premises and select the correct conclusion.

Example 3:

Major premise: All engineers are innovative.

Minor premise: All students are engineers.

Conclusions:

1. All innovative are students

2. All students are innovative
3. No innovative are students
4. No engineers are students
Solution:

Explanation:
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The first conclusion “ All innovative are students” is wrong according to case 1 and case
2. The second conclusion is correct in all three cases. Conclusion 3 and 4 are not correct
according to all the three cases. Hence the correct answer is option B.

Example 4:

Major premise: No computers are televisions.

Minor premise: All radios are televisions.

Conclusions:

1. All radios are computers

2. No radios are computers
3. All computers are radio
4. None of the above
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Explanation:

The conclusion “ All radios are computers” is not true according to both the Venn
diagrams. The second conclusion is true, according to both the diagrams. As both the
Venn diagrams do not overlap with each other anywhere. The conclusion “ All
computers are radio” is also wrong according to both the diagrams. Hence the correct
answer is option B.

Type 3 questions of syllogisms.

Example 5:

Statements:

1. All Stones are Hammers

2. No Hammer is Ring
3. Some rings are doors
4. All doors are windows
Conclusions:

1. Some hammers are stones

2. Some windows are rings
3. Only (1) conclusion follows
4. Only (2) conclusion follows
5. Either(1) or (2) follows
6. Neither(1) nor (2) follows
7. Both (1) and (2) follow
Solution:
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Explanation:

The first conclusion “Some hammers are stones” is not true according to case 5, where
all the shammers are stones. The second conclusion” Some windows are rings “ is true
in all the three cases. Hence the correct answer option is B.

Example 6:

Statements:
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All cups are books.

All books are shirts.

Conclusions:

i. Some cups are not shirts.

ii. Some shirts are cups.

1. Only (1) conclusion follows

2. Only (2) conclusion follows
3. Either(1) or (2) follows
4. Neither(1) nor (2) follows
5. Both (1) and (2) follow
Solution:

Explanation:

Four combinations of Venn diagrams are possible according to the two premises. The
first conclusion “some cups are not shirts” is not true in all the three cases, as all the
cups are shirts in every case. The second conclusion “ some shorts are cups” is true
only in the first three cases, whereas in the last case it’s not true(all the shirts are cups).
Hence neither conclusion 1 nor 2 is correct. Hence the correct answer is option D.