Shortcut to solve syllogism by rules
Day 6: Certain Controversy and Exceptional Case
Two Exceptional Case of SOME NOT
On Day 3 we learned a rule that SOME NOT + ANYTHING = NO CONCLUSION
Here we will see two exceptional cases in which SOME NOT and ALL are involved. Rest everything can be solved by using the table discussed on Day 3.
In Rest All case of SOME NOT + ALL or Any other proposition we will get NO CONCLUSION
Example 1: Some A are not B + All B is C. Here the common term B is neither in the starting in both the proposition neither at the end in both proposition. So exceptional case is not valid here.
Example 2: Tell which of the following conclusion follows
All red is pink
Some red is not green
I. Some green are not pink
II. Some Pink are not green
Example 3: Tell which of the following conclusion follows
Some blue are not green
All red is green
I. Some blue are not red
II. Some red are not blue.
|1||Does restatement follows?||As explained on Day 5 The Rule is
1) Restatement Follows
2) Possibility of Restatement Doesn’t Follows
Example: Statement: Some A are B
Conclusion: Some A are B(Follows)
Some A are B is a possibility(Doesn’t Follows)
|2.||Does Some A is B means Some A are Not B or vice versa?||NO. It does not means.|
|3.||Does All + No makes complimentary pair?||NO. They don’t. On Day 5 we have covered this topic|
All A are Not B ???
What does it means
|This is a controversial statement which can have two meaning. So you will never get this statement in exam.|
Certain Special words used in Syllogism and their meaning
|Atleast, Most, Many, few||SOME||Atleast some A are B*
Most A are B
Many A are B
Few A are B
=> Some A are B
*In exams you will mostly find the case of Atleast.
|Only||Statement: Only A is B||Conclusion: All B is A|
Trick to solve the new pattern syllogism in short time using rules
By using rules we can solve the new pattern reverse syllogism questions in very less time. We can further reduce this time by having a correct thought process while solving the question. In the below example we will show the right approach to solve such question.
Example 4: Conclusions: Some cars are not trucks. Some buses are trucks.
A) All cars are scooters. No bus is scooter. Some busses are trucks.
B) All cars are scooters. No truck is scooter. All trucks are busses.
C) All cars are scooters. All bus are scooters. All trucks are busses.
D) Some cars are scooters. No truck is scooter. No bus is car.
Now how to tackle such questions? You can either check all the option and get the correct answer easily. Or you can simultaneously use elimination and reduce the number of options that you have to check. To eliminate wrong options follow this approach:
One of the Conclusion is SOME NOT : When do we get SOME NOT? We get one SOME NOT when one of the proposition is SOME and another is NO. OR we can also get SOME NOT when tthere is case of NO :example No A is B also means that Some A is Not B. So even If All + No is there we can get SOME NOT.
So check in each option at a glance which option does not contains Some + No OR All + No together And eliminate that option as that cannot be the answer.
So we get Option C) cannot be the ans as it has Only ALL.
Now go to the second conclusion: We have the case of SOME. When do we get SOME? We get Some when the first proposition is Some and the second is All. Or both is ALL. Now scan the remaining options which does not have either Some+ All or All + All together. So see that Option D is also eliminated.
Now we are left with only Option A) and B) now use the rules and check both the case. And get the final answer. You can practice this though process now and gain expertise over it and use it in real exam.
Questions for Practise
(i) All red is blue is a possibility.
(ii) All green being yellow is a possibility.
A) All red is yellow. All yellow is blue. No blue is green.
B) Some red is yellow. No yellow is blue. Some blue is green.
C) Some red is yellow. Some yellow is blue. No blue is green.
D) All red is yellow. No yellow is blue. All blue is green.
(i) Some business are express
(ii) Some express are times
A) All business are standard. All standard is times. Some times are express.
B) All business is standard. Some standard are times. All times are express.
C) No business is standard. All standard are times. Some times are express.
D) Some business is standard. All standard is times. No times is express
(i) Some heater are lamp.
(ii) Some fan are lamp.
A) All lamp are bulb. All bulb are fan. Some fan are heater.
B) All lamp are bulb. Some bulb are fan. All fan are heater.
C) Some lamp are bulb. All bulb are fan. All fan are heater
D) All lamp are bulb. All bulb are fan. Some fan are heater.
(i) Some tulip are not lily.
(ii) Some flower are rose.
A) Some rose are not lily. All rose are tulip. All tulip are flower.
B) All tulip are rose. Some lily are not rose. Some tulip are flower.
C) All rose are lily. No lily is tulip. No tulip are flower.
D) Some rose are lily. No lily is tulip. Some tulip are flower
(i) All water being river is a possibility
(ii) Some ocean are not lake.
A) Some lakes are water. All water us ocean. No ocean is river.
B) All lakes are water. All water is ocean. Some ocean is river.
C) All lakes are water. No water is ocean. Some ocean is river.
D) Some lakes are water. Some water is ocean. All ocean is river.
This is the end of the course in Syllogism by Rules.
Ask your doubt in comment section.