Test 2 Flashcards
(41 cards)
Quality of A,E,I, and O statements?
A– affirmative
E– negative
I– affirmative
O– negative
What are the four standard forms of categorical statements?
A– all A are B
E– no A are B
I– some A are B
O– some A are not B
What is the quantity of A,E,I, and O statements?
A– universal
E– universal
I– particular
O– particular
An inference is immediate when?
A conclusion is drawn from only one premise
Corresponding statements are?
Categorical statements having the same subject term and the same predicate term
Two statements are contradictories if?
They cannot both be true and they cannot both be false
Two statements are contraries if?
They cannot both be true but they can both be false
A statement is a necessary truth if?
It is true and it cannot be false under any possible circumstances
Two statements are subcontraries if?
They cannot both be false but they can both be true
A statement is a necessary falsehood if?
It is false and it cannot be true in any possible circumstance
Subalteration is?
The logical relationship between a universal statement and its corresponding particular statement
The universal statement is the _____ and the particular statement is the ______.
Superaltern, subaltern
The converse is formed by?
Interchanging its subject and predicate terms
Conversion is?
The inference from a categorical statement to its converse
Conversion by limitation is?
The inference in which we switch the subject and the predicate terms of an A statement and chance the quantity from universal to particular.
Ex: all seaweeds are plants
So, some plants are seaweeds
The complement of a class is?
The class containing all things that are not a member of class X
The term complement is?
The word or phrase that denotes the class complement
The obverse is formed by?
1– changing its quality
2– replacing the predicate term with its term complement
Ex: all trees are plants, so– no trees are non-plants
Some trees are oaks, so– some trees are not non-oaks
Obversion is?
The inference from a categorical statement to its obverse
The contrapositive is formed by?
1– replacing the subject term with the term compliment of its predicate term
2– replacing the predicate term with the term compliment of its subject term
Ex: all cats are mammals, so all non-mammals are non-cats
Contraposition is?
The inference from a categorical statement to its contrapositive
Contraposition by limitation is?
The inference in which we (1) replace the subject term of an E statement with the term compliment of the predicate term (2) replace the predicate term with the term compliment of the subject term and (3) change the quantity from universal to particular.
The middle term of a categorical syllogism is?
The term that occurs once in each premise
The major term of a categorical syllogism is?
The predicate term of the conclusion
