Categorical Propositions Flashcards
What is a categorical proposition?
Relates subject and predicate terms
Subject and predicate term
Noun or noun phrase
A
Ay S are p
E
No P are s
I
Some pare s
O
Some p are not s
quantifier
“All” or “no”
Cupola
“Are” “are not”
Standard form
A statement having a quantifier and also subject and predicate terms linked by a cupola
Quality
Either affirmative or negative depending on whether it affirms or denies class membership
Quantity
Either universal (all) (no) or particular (some) depending on whether it makes a claim about every member of a set or just same some
Distribution
A term is distributed only if the proposition assigns an attribute to every member of the class represented by that term. Applies to terms not propositions
Aristotelian (traditional) perspective
Universal propositions about existing things have existential import, though those that are about non existing things dent don’t
The Boolean (modern) perspective
No universal propositions have existential import
Vacuously true
Universal propositions that have as their subjects a class of objects that don’t exist are true simply in virtue of the fact that they speak of an empty class
Vacuously false
Particular propositions that have as their subjects a class of objects that don’t exist are false simply i virtue of the fact that they are contrary of a true universal proposition that has as its subject a class of objects that are vacuous
Immediate inference
Have single categorical propositions as the only premise and then proceed immediately to the conclusion
Existential fallacy
Formal fallacy of the Boolean logic that occurs whenever an argument is invalid merely because the premise ingles lacks existential import
Conversion
An operation wherein the subject and predicate switch places (only can be used for E and I )
Obversion
Two steps: 1.) change quality (affirm.or neg.) NOT quantity ( univ. Or part.) and 2.) replace predicate with term compliment (non-x)
Contraposition
Two steps: 1.) subject and predicate switch and 2.) replace each word wi its term compliment
Fallacy of illicit conversion
When you commit conversion to an a or O proposition
Fallacy of illest contrapostition
When you preform contrabosition to either E or I propositions
Contradictory relation
Opposite truth value (A-0) ( e- I)
Contrary relation
At least one is false (A – E)
Sub contrary relation
At least one is true (1-0)
Sub alternation relation
Truth “trickles down” from A to I and £ to o and falsity “floats up” from I to A to to E
Illicit contrary
When a premise/conclusion are related by the contrary relation, the premise is false and the conclusion asserts its either t/f
Illicit subcontrary
When a premise conclusion are related by the subcontrary relation, the premise is true and the conclusion asserts its either t/f
Illicit subalternation
When a premise/conclusion are related by the subalternation relation in a way that yields a logically indeterminate truth value, but the conclusion States a determinate truth value.
Conditionally valid
. Applies to an argument from the Aristotelian standpoint when we are not certain whether the subject term of the premise actually denotes an existing thing
