SYLLOGISM - A syllogism is a kind of logical argument that applies deductive reasoning to arrive at a
conclusion based on two or more propositions that are asserted or assumed to be true. Deductive
reasoning.
QUESTIONS ASKED IN EXAM – (2 – 5)
TYPES
ORDINARY
EITHER OR CONDITION
POSSIBILITY
REVERSE SYLLOGISM
RULE METHOD
Based on given statement we have to find the conclusion is valid and in Reverse syllogism using given
conclusion we have to confirm which statement should form a valid given conclusion.
Questions have this statements like – UP, UN, PP AND PN
CONVERSION ORDER – PP>UN>UP
UP – STATEMENT LIKE – {ALL, EVERY, 100%, ONLY, NONE BUT, ALWAYS, ANY, EACH}
UN – STATEMENT LIKE – {NO, 0%, ALL NOT, NONE, NEVER}
POSSIBILITY – {CAN BE, MAY BE, CHANCES, OCCURS, MIGHT BE}
CAN NEVER BE – Definitely not
EXAMPLES OF STATEMENTS
1. ALL A IS B – TAKE AS UP
2. NO A IS B – TAKE AS UN
3. SOME A IS B – TAKE AS PP
4. SOME A IS NOT B – TAKE AS PN
NO CONCLUSION
UP+PP --- NO CONCLSUIONS
UN+UN--- NO CONCLSUIONS
PP+PP--- NO CONCLSUIONS
PN+ANYTHING or ANYTHING + PN ------ NO CONCLSUIONS (SOME EXCEPTIONAL CASES THERE
MENTIONED BELOW)
CONCLUSIVE COMBOS
1. UP+UP ---- UP (A – C STATEMENTS) – ALL
2. UP+UN ----- UN (A – C STATEMENTS) – NO
3. PP+UP ---- PP (A – C STATEMENTS) – SOME
4. PP+UN ---- PN (A – C STATEMENTS) – SOME NOT
5. UN+UP---- PN (C – A STATEMENTS) -- SOME NOT REVERSED
6. UN+PP ---- PN (C – A STATEMENTS) --- SOME NOT REVERSED
STATEMENTS CAN WRITTEN AS
NONE BUT – UP – NONE BUT A IS B WRITTEN AS ALL B IS A
ONLY – UP – ONLY A IS B WRITTEN AS ALL B IS A
ALL A NOT B – WRITTEN AS NO A IS B – UN STATEMENT
NOT A IS B – WRITTEN AS SOME A NOT B – PN STATEMENT
NOT ALL A IS B WRITTEN AS SOME A NOT B – PN
A FEW – FEW – ALONE – ATLEAST – MOST – MANY – SOME STATEMENT - PP
THEN IF THEN – ALL STATEMENT – UP
SOLVE USING PROPER ARRAGEMENTS
ALL A IS B
SOME C IS B
WRITE AS
(ALL A IS B
SOME B IS C to deduct btw A AND C CONCLUSION)
EITHER OR – COMPLEMENTARY PAIR HAS THE FOLLOW BELOW CONDITION
IF EITHER OR IN CONCLUSION STATEMENT
IF NO CONCLUSION COMES FROM DEDUCTIONS
SAME SUBJECT AND SAME PREDICATE
IT IS NOT APPLICABLE FOR THE STATEMENT COMBO – “UP+UN OR ALL + NO “
APPLICABLE TO FOLLOWING STATEMENT COMBOS
1. SOME + SOME NOT – PP + PN or PN + PP (ex)
STATEMENT HAS TO BE LIKE
SOME A ARE B
SOME A NOT B
OR
SOME B IS A
SOME A NOT B
2. SOME + NO – PP + UN or UN + PP (ex)
STATEMENT HAS TO BE LIKE
SOME A IS B
NO A IS B
Or
SOME B IS A
NO A IS B
3. ALL + SOME NOT – UP + PN or PP + UP (ex)
STATEMENT HAS TO BE LIKE
ALL A IS B
SOME NOT A IS B
WRONG IF STATEMENT ALL A IS B AND SOME NOT B IS A
EXCEPTIONAL CASES FOR SOME NOT + ALL
APPLICABLE ONLY FOR THE COMBO –SOME NOT + ALL STATEMENT OR ALL + SOME NOT MEANS
(UP+PN or PN+UP)
CONDITION – 1
IF SAME ENTITY AT BEGINNING
ALL A IS B
SOME A NOT C SAME ENTITY A IS IN BEGINNING – GIVES SOME NOT AS CONCLUSION
ARRANGE THE ABOVE AS
SOME A NOT C
ALL A IS B DOWN TO UP – CONCLUDE AS SOME B NOT C
CONDITION – 2
IF SAME ENTITY AT END
SOME A NOT B
ALL C IS B SAME ENTITY B AT END – GIVES SOME NOT AS CONCLUSION
ARRANGE THE ABOVE STATEMENT AS
ALL C IS B
SOME A NOT B --- DOWN TO UP – CONCLUDE AS SOME A NOT C
OR MEMORIZE AS
SOME NOT + ALL IF SAME ENTITY IS IN BEGINNING
WRITE CONCLUSION AS --- SOME (ENTITY END AT ALL) NOT (ENTITY END AT SOME NOT) OMIT THE SAME
ENTITY
EXAMPLE – SOME A NOT C + ALL A IS B – WRITE AS SOME B NOT C
SOME NOT + ALL IF SAME ENTITY AT END
WRITE CONCLUSION AS --- OMIT THE SAME ENTITY ---- SOME (ENTITY BEGING AT SOME NOT) NOT
(ENTITY BEGIN AT ALL)
EXAMPLE - SOME A NOT B + ALL C IS B – WRITE AS SOME A NOT C
CONEVERSION OF STATEMENTS
UP – PP BOTH SIDES
UN – UN OR PN OPP SIDES
PP – PP OPP SIDES
PN – CAN’T CONVERT
CONVERSION ORDER – PP>UN>UP
EXAMPLES OF CONVERSIONS
ALL A IS B = SOME A IS B OR SOME B IS A
SOME A IS B = SOME B IS A
NO A IS B = NO B IS A OR SOME B NOT A OR (SOME A NOT B IS DOUBT NOT SURE)
SOME A NOT B = NO CONVERSIONS
POSSIBILITY STATEMENTS
ALL A IS B = ALL B A AND SOME B NOT A – 2 POSSIBILITY STATEMENTS
SOME A IS B = ALL B A, ALL A B, SOME A NOT B AND SOME B NOT A - 4 POSSIBILITY STATEMENTS
SOME A NOT B = ALL B A, NO A B, NO A B, SOME B NOT A, SOME AB AND SOME BA - 6 POSSIBILITY
STATEMENTS
NO CONCLUSION COMES – ALL POSSIBILTY IS TRUE
OTHER IMP RULE
IF CONCLUSION HAS SAME STATEMENT FROM QUESTION – RESTATEMENT FOLLOWS
EX- ALL A IS B IN QUESTION – IN COLUSION ALL A IS B GIVEN THEN - IT IS TRUE
BUT POSSIBILITY AND DEFINITE RESTATEMENT - NOT FOLLOWS
EX – ALL A IS B POSSIBILITY – IN CONCLUSION ALL A IS B POSSIBILITY – IT IS FALSE
EX – ALL A IS B DEFINITELY – IN CONCLUSION ALL A IS DEFINITELY B – IT IS FALSE
(other method to solve Syllogism – Venn diagram and Deduction method**need to learn)
*************** {PRACTICE LEAST 50 QUESTIONS FROM EACH TYPE} ***********************
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(TAKE NEARLY 2 MINS FOR 5 QUESTIONS)
Other imp type of questions from statements model are
STATEMENT – ASSUMPTION
STATEMENT – COURSE OF ACTION
STATEMENT – INFERENCE CAN BE SOLVED ONLY IF GOOD AT ENGLISH
STATEMENT – ARGUMENTS
STATEMENT – THEME DETECTION
(FOR THE ABOVE TAKE 1 MINS FOR 2 QUESTIONS)
