Categorical Propositions
Categorical Propositions
Categorical Propositions
PROPOSITIONS
CATEGORICAL PROPOSITIONS
SYLLOGISMS
All A are E.
Some S are A. T T T T T T T T
Therefore, some S are E. T T F T T T T T
T F T F T F F T
Each categorical propositions are T F F F T F T T
conditional propositions, hence we can
say that: F T T T F F T T
F T F T F F T T
F F T T F F F T
F F F T F F T T
VALIDITY OF CATEGORICAL
SYLLOGISMS
In the previous example, the implication of the conjunction
of the two premises and the conclusion is a Tautology,
therefore the argument “Harry Potter realizes that all avada
kedavra are expelliarmus and some stupefy are avada
kedavra. Some stupefy are expelliarmus.” is valid.
VALIDITY OF CATEGORICAL
SYLLOGISMS
Example: Determine the validity of the following
categorical syllogisms.
SYLLOGISMS
All B have W.
M have W. T T T T T T T T
Therefore, M are B. T T F F T F T T
T F T T F F T T
Each categorical propositions are T F F F T F T T
conditional propositions, hence we can
F T T T T T F F
say that:
F T F T T T T T
F F T T F F F T
F F F T T T T T
VALIDITY OF CATEGORICAL
SYLLOGISMS
In the previous example, the implication of the conjunction of the
two premises and the conclusion is NOT a Tautology, therefore the
argument:
All birds have wings.
Mulawins have wings.
Therefore, Mulawins are birds.
Is NOT VALID.