Logical Reasoning - Logical Problems - Discussion

Discussion Forum : Logical Problems - Type 1 (Q.No. 3)
Directions to Solve
Each problem consists of three statements. Based on the first two statements, the third statement may be true, false, or uncertain.

3.
All the trees in the park are flowering trees.
Some of the trees in the park are dogwoods.
All dogwoods in the park are flowering trees.
If the first two statements are true, the third statement is
true
false
uncertain
Explanation:
All of the trees in the park are flowering trees, So all dogwoods in the park are flowering trees.
Discussion:
42 comments Page 4 of 5.

Sujay bain said:   1 decade ago
But it is not mentioned anywhere that "all dogwoods are trees". So, those dogwood which are not tree can may not be flowering trees.

If we use the venn diagram the result is invalid. And also according to rules of syllogism the conclusion is invalid because in syllogism, if one of the premises of a statement is particular the conclusion should be particular.

Moses xhao sondash said:   1 decade ago
The 3rd premise doesn't logically follow from the first two premises, in syllogism, if one of the premises is universal (with a quantifier All) and the other is particular (Some) the conclusion should be particular hence wrongly deducted.

If you use the venn diagram, the result is invalid. Also, when you follow the three rules of syllogism you will see that the conclusion is invalid. If we look at the conclusion, the subject (Dogwoods) is not distributed in any of the premises which violates rule #3 of the rules of syllogism.

Nivedita Devraj said:   1 decade ago
Still its absurd cause of the statement - "Some of the trees in the park are dogwoods".

If you use the venn diagram, the result is invalid. How come it is true?

1. all the trees in park is flowering tree
so dogwoods is one kind of tree which is planted in the park
you can say like a classification of tree
so, any kind of tree planted in park is flowering tree

All the trees in the park are flowering trees.

So, a flowering tree should satisfy two conditions.

1. It should be a Tree (Some of the trees in the park are dogwoods).
2. It should be in the Park (Some of the trees in the park are dogwoods).

Since, dogwoods satisfy the above conditions, "All dogwoods in the park are flowering trees" - True.

Note: If the dogwoods outside the park, it may or may-not be flowering trees.