Logic Test #2 Study Guide Flashcards
What are the 3 Mental Acts?
Simple Apprehension
Judgment
Deductive Inference(Composition/Division)
What are the 3 Verbal Expressions?
Term
Proposition
Syllogism
What is Logic?
The science of right thinking or The act of thinking
Why are terms important?
They are good for understanding [arguements]
What does a Logical Form include?
Subject, Predicate, & Copula
What do “S, C, P” all express?
They are abbreviations for the subject-term, predicate-term, and copula
What does a Proposition include?
Subject-term, Predicate-term, & Copula
What is an example of a Proposition?
“All men are mortal”
“Socrates is a man”
“Socrates is mortal”
How do we derive a Contraposition?
Obvert it, Convert it, Obvert it again = Contraposition
Nominative Predicate?
It tells us about the subject
Logical Form
form in which a sentence must be in, in order to be handled logically
Proposition
a sentence or statement that expresses truth or falsity
Judgment
the mental act whose verbal expression is a proposition
Quality
(of a proposition) has to do with whether it’s affirmative or negative
Quantity
(of a proposition) has to do with whether it’s universal or particular
Contradictory Statements
statements that differ in both quality & quantity
Contraries
statements that are both universal statements, but differ in quality
Subcontraries
statements that are both particular statements, but differ in quantity
Subalterns/Subalternates
statements that have the same quality, but differ in quantity
Distribution
the status of a term in regard to its extension
Obversion
the change in quality and negation of the predicate
What are the 2 Qualities?
Affirmative(Affirmo)
Negative(Nego)
What are the 2 Quantities?
Universal(singulars)
Particular
Conversion
the switch of the subject(S) with the predicate(P)
Particulars
a subset of universals- all particulars are derived from universals
Which statements are Contraries?
A & E
Which statements are Subcontraries
I & O
Which statements are Subalterns/Subalternates?
A with I & E with O
Which statements are Contradictories?
A with O & E with I
What is the form of A statements?
All S is P
What is the form of E statements?
No S is P or All S is not P
What is the form of I statements?
Some S is P
What is the form of O statements?
Some S is not P
Rule of Contradiction
contradictory statements are statements that differ in both quality & quantity
Rule of Contraries
2 statements that are contrary to one another, if they’re both universals, but differ in quality
Rule of Subcontraries
2 statements that are subcontrary, if they’re both particular, but differ in quality
Rule of Subalterns/Subalternates
2 statements that are subalternate, if they have the same quality, but differ in quantity
1st Law of Opposition
contradictories can’t at the same time be true nor at same time be false
2nd Law of Opposition
contraries can’t at the same time both be true, but can at the same time both be false
3rd Law of Opposition
subcontraries may at the same time both be true, but can’t at the same time both be false
4th Law of Opposition
subalterns may both be true or false. If particular is false, universal is false; If universal is true, then particular is true; otherwise, then status is indeterminate
What parts of an A statement are Distributed and Undistributed?
Subject-term is DISTRIBUTED
Predicate-term is UNDISTRIBUTED
What parts of an I statement are Distributed and Undistributed?
Subject-term is UNDISTRIBUTED
Predicate-term is UNDISTRIBUTED
What parts of an E statement are Distributed and Undistributed?
Subject-term is DISTRIBUTED
Predicate-term is DISTRIBUTED
What parts of an O statement are Distributed and Undistributed?
Subject-term is UNDISTRIBUTED
Predicate-term is DISTRIBUTED
What quality & quantity is an A statement?
Affirmative
Universal
What quality & quantity is an E statement?
Negative
Universal
What quality & quantity is an I statement?
Affirmative
Particular
What quality & quantity is an O statement?
Negative
Particular
What are the types of Universal statements?
Singular, All, and Every
What is the chart with the qualities and quantities of all 4 statements called?
Square of Opposition
What is a Copula?
are (not)
What are the Mental Acts & Verbal Expressions together called?
Acts of the Intellect
What is the Subject, Predicate, and Copula of the statement: All elephants are pachyderms.
Subject- Elephants
Predicate- pachyderms
Copula- are
How do you change this sentence into a statement: Elephants love to blow bubbles?
All elephants are animals(pachyderms) who love to blow bubbles.
Modus Pollens
P is to Q
P
therefore Q
Modus Tollens
P is to Q
~Q
therefore ~P
What is Modus Pollens doing?
It is affirming the antecedent
What is Modus Tollens doing?
It is denying the consequent
Denying the Antecedent
P is to Q
~P
therefore ~Q
Affirming the Consequent
P is to Q
Q
therefore P
Example of the process of a Contraposition with “All cats are animals.”
(obversion) All cats are not non-animals
(conversion) All non-animals are not cats
(obversion) All non-animals are non-cats <-contraposition
Example of the process of an obversion with “Some flowers are not red.”
some flowers are not RED
some flowers are NOT RED
Example 2 of the process of an obversion with “Some flowers are not non-red things.”
some flowers are not non-red things
some flowers are RED
