2. Good Day Every One!!!
This Video is all about the
Four kinds of Logical Opposition.
Our final Project for Humanities II
(Social Philosophy and Logic)
…………….Enjoy Watching……………..
3. It refers to the relationship existing
between two proposition having the same
subject and the same predicate but differ
in quantity or in quality or in quality or
both in quantity or quality.
LOGICAL OPPOSITION
4. Four Kinds of Logical Opposition
1. Contrary Opposition
2. Contradictory Opposition
3. Sub- Contrary Opposition
4. Sub- Altern Opposition
5. 1. Contrary Opposition
One which exist between two universal
proposition that differ in quality
Two propositions with the same subjects
and predicates but different qualities and
having the same universal quantities.
7. Examples:
A: All Cats are Dogs. (F) A: All Diamonds are Gems. (T)
E: No Cats are Dogs. (T) E: No diamonds are Gems. (F)
A: All Flowers are Roses. (F)
E. No Flowers are Roses. (F)
Thus, “If one is true the other is false; If one is false the other is doubtful.”
8. 2. Contradictory Opposition
One which exist between two proposition
that differ in both quality or quantity
Two propositions with the same subjects
and predicates but different in quantities
and in qualities.
10. Example:
A: All Dogs are Animals. (T)
O: Some Dogs are not Animals. (F)
E: no women are married. (F)
I. Some Women are married. (T)
Thus, “If one is true the other is false or vice versa.”
11. 3. Sub- Contrary
Proposition
One which exist between two particular
propositions that differ only in quality.
Two particular propositions with the same
subjects and predicates but different
qualities.
13. Examples:
I: Some Basketball Players are tall. (T)
O: Some Basketball Players are not tall.
O: Some Triangles are not Squares. (T)
I; Some Triangles are Squares. (F)
I: Some Students are present. (F)
O: Some Students are not present. (T)
Thus, “If one is true the other is false; If one is true the other is doubtful.”
14. 4. Sub- Altern
Opposition
One which exist between two propositions
that differ in quality.
Two propositions with the same subjects
and Predicates both with the same
qualities and different only in qualities.
16. Examples:
A: All Dogs are Animals.(T)
I: Some Dogs are Animals. (T)
E: No Cats are Dogs. (T)
O: Some Cats are not Dogs. (T)
Thus, “If the universal is true the particular is true but if the universal is false, the
particular is doubtful or vice versa.