A syllogism has two or more statements followed by conclusions. You must check if the conclusions logically follow from the statements, ignoring what you know about the real world
💡Key Rules
(1) Accept all statements as true, even if they seem wrong in reality. (2) Use only the given information. (3) Draw conclusions based purely on logical connections. (4) 'Some' means 'at least one but not all'. (5) 'All' means '100% without exception'
🔑Venn Diagram Method
This is the most reliable approach. Draw circles to represent each category mentioned in statements. Overlap circles based on relationships given in statements. Check if conclusions match your diagram.
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Exam Patterns
What examiners ask — read before attempting PYQs
📋SSC CGL typically asks
(1) Statement-Conclusion type (2-3 statements, 2-4 conclusions to verify) (2) Only conclusion follows questions (3) Possibility-based conclusions. Most questions use words like All, Some, No, Few.
Shortcut Formula #1 - Conversion Rule: 'All A are B' can be converted to 'Some B are A'. But 'All A are B' cannot be converted to 'All B are A'.
Shortcut Formula #2 - Negative Conclusions: If both statements are positive, the conclusion cannot be negative. If one statement is negative, the conclusion must be negative
✏️Worked Example 1
Statements: (1) All roses are flowers (2) Some flowers are red
Conclusions: (I) Some roses are red (II) All red things are flowers
Solution: Draw three circles - Roses (inside Flowers circle), Flowers (big circle), Red (overlapping with Flowers). From the diagram, roses and red may or may not overlap. Conclusion I is 'possible but not definite' - so FALSE. Conclusion II says all red are flowers, but statement 2 only says some flowers are red, not the reverse - so FALSE
→Answer
Neither conclusion follows
✏️Worked Example 2
Statements: (1) No cats are dogs (2) All cats are animals
Conclusions: (I) No dogs are cats (II) Some animals are cats
Solution: Draw separate circles for cats and dogs (no overlap due to 'No'). Draw animals circle containing cats circle completely
→Conclusion I
'No dogs are cats' is the same as 'No cats are dogs' - TRUE
→Conclusion II
Since all cats are animals, definitely some animals are cats - TRUE
→Answer
Both conclusions follow.
Trick #3 - Possibility Conclusions: When a conclusion uses 'Some X can be Y' or 'X is a possibility', it's asking if the relationship is possible, not definite. Even if something is not proven definite, it might still be possible.
Common Mistake #1: Students use real-world knowledge instead of logical reasoning. For example, if given 'All books are tigers', students reject it as impossible. In syllogism, you must accept this as true for that question and proceed logically
⚡Time-Saving Approach
For statement-conclusion questions, quickly eliminate obviously wrong conclusions first. Look for direct contradictions with statements. Then use Venn diagrams only for remaining conclusions. This saves precious exam time.
Medium/Definite Rule: If conclusion says 'definitely' or uses strong words like 'certainly', it needs 100% proof from statements.
If it says 'can be' or 'possible', it needs only logical possibility, not certainty.
Read the following statements carefully and answer the question.
Statements:
1. All teachers are educated.
2. Some educated people are not disciplined.
3. No disciplined person is lazy.
Which of the following conclusions logically follows from the above statements?
A) All teachers are disciplined.
B) Some teachers are lazy.
C) Either all teachers are disciplined or some teachers are not disciplined.
D) No teacher is lazy.
Practice 2medium
Statements:
1. All musicians are artists.
2. Some artists are not performers.
3. All performers are entertainers.
Conclusion: Some musicians are not entertainers.
Is the conclusion valid?
Practice 3medium
Statements:
1. All athletes are disciplined individuals.
2. No lazy people are disciplined individuals.
3. Some students are lazy people.
Conclusion: Some students are not athletes.
Is the conclusion valid?
Practice 4medium
Statements:
1. No reptiles are warm-blooded animals.
2. All snakes are reptiles.
Conclusion: No snakes are warm-blooded animals.
Is the conclusion valid?
Practice 5medium
Read the following statements carefully and answer the question.
Statements:
1. All engineers are problem-solvers.
2. Some problem-solvers are not innovators.
3. No innovator is lazy.
Which of the following conclusions is definitely true?
A) All engineers are innovators.
B) Some engineers are lazy.
C) Either all problem-solvers are innovators or some engineers are not innovators.
D) No engineer is lazy.
Practice 6medium
Statements:
1. All engineers are problem-solvers.
2. Some problem-solvers are not creative.
Conclusion: Some engineers are not creative.
Is the conclusion valid?
Practice 7hard
Study the following statements carefully and answer the question:
Statement 1: All engineers are problem-solvers.
Statement 2: Some problem-solvers are not innovators.
Statement 3: No innovators are lazy.
Which of the following conclusions is/are definitely true?
I. Some engineers are not innovators.
II. All lazy people are not problem-solvers.
III. Either all engineers are innovators OR some engineers are not innovators.
60-Second Revision — Syllogism
Remember: Accept all statements as true, ignore real-world knowledge
Formula: All A→B converts to Some B→A, not All B→A
Trap: Using real-world logic instead of pure logical reasoning
Method: Use Venn diagrams for visual clarity and accuracy
Rule: Positive statements cannot produce negative conclusions
Trick: Eliminate contradictory conclusions first to save time
Focus: 'Some' = at least one, 'All' = 100%, 'Possible' = logically feasible