Logical Reasoning - Logical Deduction - Discussion

In each of the following questions, two statements are given followed by three or four conclusions numbered I, II, III and IV. You have to take the given statements to be true even if they seem to be at variance from the commonly known facts and then decide which of the given conclusions logically follows from the given statements disregarding commonly known facts.

4. 

Statements: All politicians are honest. All honest are fair.

Conclusions:

  1. Some honest are politicians.
  2. No honest is politician.
  3. Some fair are politicians.
  4. All fair are politicians.

[A]. None follows.
[B]. Only I follows.
[C]. Only I and II follow.
[D]. Only I and III follow

Answer: Option D

Explanation:

Clearly, it follows that 'All politicians are fair'. I is the converse of the first premise, while III is the converse of the above conclusion. So, both I and III hold.

Suchitra said: (Aug 4, 2013)  
How can 1 follow? Fair is distributed in the conclusion without being distributed in the premises. How can 4th conclusion follow?

Answer should be A.

Since.

1st and 3rd conclusion is particular it cannot follow.

2nd is negative so it cannot follow.

4th conclusion distributes fair without it being distributed in the premises. So none can follow.

Aurobindo Ghosh said: (May 18, 2016)  
Right answer is definitely IV.

If the statement says "All politicians are honest. All honest are fair. ", then the asnwer is "All fair are politicians. ".

Post your comments here:

Name *:

Email   : (optional)

» Your comments will be displayed only after manual approval.