PPT: Syllogism | Logical Reasoning for CLAT PDF Download

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S y l l o g i s m
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S y l l o g i s m
What is Syllogism?
Definition
A syllogism is a form of reasoning 
where a conclusion is drawn from two 
given premises. These premises are 
statements that are assumed to be 
true, and the conclusion must logically 
follow from them.
Types of Premises
Type 1: All As are Bs (Universal 
Affirmative)
Type 2: Some As are Bs (Particular 
Affirmative)
Type 3: No A is B (Universal Negative)
Type 4: Some As are not Bs (Particular 
Negative)
Valid Reactions
When "All As are Bs," a valid 
conclusion would be "Some As are 
Bs." Similarly, when "No A is B," we 
can validly conclude "No B is A." 
Understanding these patterns is 
essential for solving syllogism 
problems.
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S y l l o g i s m
What is Syllogism?
Definition
A syllogism is a form of reasoning 
where a conclusion is drawn from two 
given premises. These premises are 
statements that are assumed to be 
true, and the conclusion must logically 
follow from them.
Types of Premises
Type 1: All As are Bs (Universal 
Affirmative)
Type 2: Some As are Bs (Particular 
Affirmative)
Type 3: No A is B (Universal Negative)
Type 4: Some As are not Bs (Particular 
Negative)
Valid Reactions
When "All As are Bs," a valid 
conclusion would be "Some As are 
Bs." Similarly, when "No A is B," we 
can validly conclude "No B is A." 
Understanding these patterns is 
essential for solving syllogism 
problems.
Method 1: Analytical Method
The analytical method requires understanding statement types and their conclusions.
Two Statement 
Rules
Two particulars yield no 
universal conclusion. 
Two positives can't 
produce negatives.
Statement 
Compatibility
Two negatives won't 
yield positives. 'I' type 
statements can reverse 
for new 'I' conclusions.
Single Statement 
Reversals
Type 'E' reverses to 'E 
& O'. Type 'A' reverses 
to 'I'.
Reversal 
Limitations
Type 'I' reverses to 'I'. 
Type 'O' yields no 
conclusion when 
reversed.
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S y l l o g i s m
What is Syllogism?
Definition
A syllogism is a form of reasoning 
where a conclusion is drawn from two 
given premises. These premises are 
statements that are assumed to be 
true, and the conclusion must logically 
follow from them.
Types of Premises
Type 1: All As are Bs (Universal 
Affirmative)
Type 2: Some As are Bs (Particular 
Affirmative)
Type 3: No A is B (Universal Negative)
Type 4: Some As are not Bs (Particular 
Negative)
Valid Reactions
When "All As are Bs," a valid 
conclusion would be "Some As are 
Bs." Similarly, when "No A is B," we 
can validly conclude "No B is A." 
Understanding these patterns is 
essential for solving syllogism 
problems.
Method 1: Analytical Method
The analytical method requires understanding statement types and their conclusions.
Two Statement 
Rules
Two particulars yield no 
universal conclusion. 
Two positives can't 
produce negatives.
Statement 
Compatibility
Two negatives won't 
yield positives. 'I' type 
statements can reverse 
for new 'I' conclusions.
Single Statement 
Reversals
Type 'E' reverses to 'E 
& O'. Type 'A' reverses 
to 'I'.
Reversal 
Limitations
Type 'I' reverses to 'I'. 
Type 'O' yields no 
conclusion when 
reversed.
Method 2: Venn Diagrams
Draw All 
Possibilities
When solving 
syllogism questions 
using Venn diagrams, 
it's crucial to 
represent all possible 
relationships between 
the sets mentioned in 
the statements.
Verify 
Conclusions
A conclusion is 
considered true only if 
it can be deduced 
from all possible Venn 
diagram 
representations of the 
given statements.
Reject Invalid 
Conclusions
If a conclusion follows 
from one possible 
Venn diagram but not 
from another, that 
conclusion must be 
rejected as false or 
invalid.
Venn diagrams provide a visual approach to solving syllogism problems, 
making it easier to see the relationships between different sets and 
determine which conclusions are valid.
Page 5


S y l l o g i s m
What is Syllogism?
Definition
A syllogism is a form of reasoning 
where a conclusion is drawn from two 
given premises. These premises are 
statements that are assumed to be 
true, and the conclusion must logically 
follow from them.
Types of Premises
Type 1: All As are Bs (Universal 
Affirmative)
Type 2: Some As are Bs (Particular 
Affirmative)
Type 3: No A is B (Universal Negative)
Type 4: Some As are not Bs (Particular 
Negative)
Valid Reactions
When "All As are Bs," a valid 
conclusion would be "Some As are 
Bs." Similarly, when "No A is B," we 
can validly conclude "No B is A." 
Understanding these patterns is 
essential for solving syllogism 
problems.
Method 1: Analytical Method
The analytical method requires understanding statement types and their conclusions.
Two Statement 
Rules
Two particulars yield no 
universal conclusion. 
Two positives can't 
produce negatives.
Statement 
Compatibility
Two negatives won't 
yield positives. 'I' type 
statements can reverse 
for new 'I' conclusions.
Single Statement 
Reversals
Type 'E' reverses to 'E 
& O'. Type 'A' reverses 
to 'I'.
Reversal 
Limitations
Type 'I' reverses to 'I'. 
Type 'O' yields no 
conclusion when 
reversed.
Method 2: Venn Diagrams
Draw All 
Possibilities
When solving 
syllogism questions 
using Venn diagrams, 
it's crucial to 
represent all possible 
relationships between 
the sets mentioned in 
the statements.
Verify 
Conclusions
A conclusion is 
considered true only if 
it can be deduced 
from all possible Venn 
diagram 
representations of the 
given statements.
Reject Invalid 
Conclusions
If a conclusion follows 
from one possible 
Venn diagram but not 
from another, that 
conclusion must be 
rejected as false or 
invalid.
Venn diagrams provide a visual approach to solving syllogism problems, 
making it easier to see the relationships between different sets and 
determine which conclusions are valid.
Different Types of Questions
Standard Format
Most syllogism questions provide two or three statements 
followed by multiple conclusions. Your task is to 
determine which conclusions logically follow from the 
given statements, even if they seem contrary to common 
knowledge.
For example: "All roses are flowers. Some flowers are 
red." From this, we can conclude "Some roses are red" 
but not "All red things are roses."
Complex Format
More complex questions may involve three statements 
with four possible conclusions, requiring careful analysis 
of all logical relationships.
When analyzing such questions, it's essential to draw all 
possible Venn diagrams to verify which conclusions are 
valid across all possible interpretations of the statements.