PPT: Syllogisms

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S y llogisms
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S y llogisms
What Are Syllogisms?
Definition
A s yllo gism is a form of logical reasoning that applies deductive reasoning to arrive at a 
conclusion based on two propositions that are asserted or assumed to be true.
Key Point: Syllogisms follow the structure: If A is true and B is true, then C must be 
true.
Major Premise
General statement about 
a category
Minor Premise
Specific statement 
about an individual
Conclusion
Logical result from both 
premises
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S y llogisms
What Are Syllogisms?
Definition
A s yllo gism is a form of logical reasoning that applies deductive reasoning to arrive at a 
conclusion based on two propositions that are asserted or assumed to be true.
Key Point: Syllogisms follow the structure: If A is true and B is true, then C must be 
true.
Major Premise
General statement about 
a category
Minor Premise
Specific statement 
about an individual
Conclusion
Logical result from both 
premises
The Classical Syllogism 
Structure
Classic Example:
Major Premise: All humans are mortal.
Minor Premise: Socrates is a human.
Conclusion: Therefore, Socrates is mortal.
This three-part structure forms the backbone of logical 
reasoning. The major premise establishes a universal rule, the 
minor premise provides a specific instance, and the 
conclusion applies the rule to that instance.
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S y llogisms
What Are Syllogisms?
Definition
A s yllo gism is a form of logical reasoning that applies deductive reasoning to arrive at a 
conclusion based on two propositions that are asserted or assumed to be true.
Key Point: Syllogisms follow the structure: If A is true and B is true, then C must be 
true.
Major Premise
General statement about 
a category
Minor Premise
Specific statement 
about an individual
Conclusion
Logical result from both 
premises
The Classical Syllogism 
Structure
Classic Example:
Major Premise: All humans are mortal.
Minor Premise: Socrates is a human.
Conclusion: Therefore, Socrates is mortal.
This three-part structure forms the backbone of logical 
reasoning. The major premise establishes a universal rule, the 
minor premise provides a specific instance, and the 
conclusion applies the rule to that instance.
Types of Statements in Syllogisms
Universal Affirmative (A)
F orm: All S are P
Ex ample: All cats are mammals
This affirms that every member of 
subject S belongs to predicate P
Universal Negative (E)
F orm: No S are P
Ex ample: No birds are mammals
This denies that any member of S 
belongs to P
Particular Affirmative (I)
F orm: Some S are P
Ex ample: Some students are athletes
This affirms that at least one S belongs 
to P
Particular Negative (O)
F orm: Some S are not P
Ex ample: Some books are not fiction
This denies that at least one S belongs 
to P
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S y llogisms
What Are Syllogisms?
Definition
A s yllo gism is a form of logical reasoning that applies deductive reasoning to arrive at a 
conclusion based on two propositions that are asserted or assumed to be true.
Key Point: Syllogisms follow the structure: If A is true and B is true, then C must be 
true.
Major Premise
General statement about 
a category
Minor Premise
Specific statement 
about an individual
Conclusion
Logical result from both 
premises
The Classical Syllogism 
Structure
Classic Example:
Major Premise: All humans are mortal.
Minor Premise: Socrates is a human.
Conclusion: Therefore, Socrates is mortal.
This three-part structure forms the backbone of logical 
reasoning. The major premise establishes a universal rule, the 
minor premise provides a specific instance, and the 
conclusion applies the rule to that instance.
Types of Statements in Syllogisms
Universal Affirmative (A)
F orm: All S are P
Ex ample: All cats are mammals
This affirms that every member of 
subject S belongs to predicate P
Universal Negative (E)
F orm: No S are P
Ex ample: No birds are mammals
This denies that any member of S 
belongs to P
Particular Affirmative (I)
F orm: Some S are P
Ex ample: Some students are athletes
This affirms that at least one S belongs 
to P
Particular Negative (O)
F orm: Some S are not P
Ex ample: Some books are not fiction
This denies that at least one S belongs 
to P
AEIOU Memory Trick
A - Affirmo
All are (Universal Affirmative)
E - nEgo
No are (Universal Negative)
I - affIrmo
Some are (Particular Affirmative)
O - negO
Some not (Particular Negative)
Pro Tip: Remember "All Elephants In Our" zoo to recall the order A-E-I-O!