Syllogism For CLAT Preparation

Syllogism is a form of deductive reasoning. In which two general statements are given, and you need to form a specific conclusion based on two statements that are assumed to be true. These assumptions or premises are given in the question, and you need to draw the most plausible conclusion. Syllogism for CLAT preparation will help you. 

Here are the four major types of statements discussed below: 

Sr. No.	Type of Statement	Denoted by the letter	Example
1.	Universal Affirmative	A	All girls are beautiful
2.	Universal Negative	E	No girl is clever
3.	Particular Affirmative	I	Some dogs are lion
4.	Particular Negative	O	Some cats are not dogs

• Universal Affirmative sentences include words like All, Every, Each, Particular name, One, Everyone.
• Universal Negative sentences will include words like None, No one, Never, Nothing.
• Particular Affirmative sentences will include words like Some, Many, Several, Very Few, Most, At least, Some.
• Particular Negative will include words like Some-not. 

While deriving the conclusions, following points should be considered:

• With two particular statements, no universal conclusion is possible.
• With two positive statements, no negative conclusion is possible.
• With two negative statements, no positive conclusion is possible.
• With two particular statements, no conclusion is possible, except when an ‘I’ type of statement is given and then by reversing it, an ‘I’ type of conclusion is given. 

You can use this table to draw conclusions-

Here O* mean that the conclusion is of type O but the subject of inference is the predicate of second the second statement and the predicate of the inference is the subject of the first statement, this means that its format is opposite to the normal format of the conclusion.

 Points to Remember

1.There are 6 cases in which no conclusion can be drawn –

• A+I = No Conclusion
• A+O = No Conclusion
• E+E= No Conclusion
• E+O = No Conclusion
• I+I = No Conclusion
• I+O = No Conclusion

2. In Syllogism, a conclusion has to be drawn from two prepositions.

3. If two prepositions have no common term then no conclusion can be drawn.

Universal Affirmative ‘A’

Example: All A are B 

From this statement we can say that: 

• Some A are B 
• Some B are A is a definite conclusion 

Note: All B are A is a possibility but it may not be true in all cases. 

Universal Negative ‘E’

Example: No A are B. 

From this statement we can say that: 

• Some A are not B 
• No B are A
• Some B are not A

Particular Affirmative ‘I’

i, ii, and iii respectively. 

Example: Some A are B 

From this statement we can say that: 

• Some B are A (i)
• However, All A are B (i)
• All B are A
• Some A are B
• Some A are not B and Some B are not A is a definite conclusion. 

Particular Negative ‘O’

Example: Some A are not B. 

No logical conclusions can be drawn from this given statement. There can be more than one possibility in which this argument can be represented. 

Conclusion:

Some dogs are cats.

Some lions are dogs. 

The shaded portion shows A, which is not B.

Understand this example- 

Example: All A are B 

From this statement we can say that: 

• Some A are B 
• Some B are A is a definite conclusion 

Note: All B are A is a possibility but it may not be true in all cases. 

Statement I. Some cats are dogs.

Statement II. Some dogs are lions.

Solution: Since both the statements are type- I, therefore, no mediate conclusion follows. But immediate conclusions can be followed from statements I and II.

Let us see the following examples:

Example 1:

Statement I. All desks are chairs.

Statement II. Some desks are cats.

Example 2:

Statement I. Some desks are chairs.

Statement II. Some cats are desks.

Example 3:

Statement I. All desks are chairs.

Statement II. All desks are cats.

From the above examples, we see that there is a common word in the two statements. Aligning the two statements means that the pair of statements must be written in a way that the common term becomes the predicate of statement I and the subject of the II statement. 

Example 1 can be converted into

I. Some chairs are desks.

II. Some desks are cats.

Example 2 can be aligned as

II. Some cats are desks.

I. Some desks are chairs.

Example 3 can be aligned as

• By converting the I statement or by changing the order of the sentences.
• Or, converting the statement II.

I. Some chairs are desks.

II. All desks are cats.              Or,

II. Some cats are desks.

I. All desks are chairs.

As per the nature of the sentences, the alignment is done:

• By converting the sentences
• Only by converting sentences.
• By changing the order of the sentences.
• By changing the order of the statements given, and converting one of the sentences.

Thus, to solve the problems of syllogism you can follow the two main steps:

• Using the conclusion table to draw the conclusions.
• Aligning the pair of sentences.

For a better understanding of this topic, you can refer to the CLAT Online Course on our website.