Two Statements are given followed by two Conclusions: Statements: All cats are dogs. All cats are black.…
Two Statements are given followed by two Conclusions:
Statements:
All cats are dogs.
All cats are black.
Conclusion-I: All dogs are black.
Conclusion-II: Some dogs are not black.
Which of the above Conclusions logically follows/follow from the two given Statements, disregarding commonly known facts?
Only Conclusion-I
Only Conclusion-II
Neither Conclusion-I nor Conclusion-II
Both Conclusion-I and Conclusion-II
Solution
From 'All cats are dogs' and 'All cats are black', cats are a subset of dogs and cats are black. But dogs that are not cats may or may not be black. So we cannot conclude all dogs are black (Conclusion-I does not follow), nor that some dogs are not black (Conclusion-II does not follow). Neither conclusion follows definitely.