Unit 2: Statements and their Relationships Flashcards Preview

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Flashcards in Unit 2: Statements and their Relationships Deck (33)
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1
Q

Define Statements

A

A sentence that is either true or false

2
Q

What type of sentences are not statements?

A

questions

commands

and nonsense sentences

are not statements because they do not have a truth value.

3
Q

What is a nonsense statement?

A

A statement that

contradicts itself

and

cannot be identified as true or false

4
Q

What is a self-supporting statement?

A

A statement whose

truth value

can be determined from the statement itself

5
Q

Self-supporting statements can be divided into three categories. What are they?

A
  1. Self-reports
  2. Statements that are true or false by logical structure
  3. Statements** that are true or false by **definition.
6
Q

What is a self-contradiction?

A

A statement that is false** due to its **logical structure.

7
Q

What is a supported statement?

A

A statement whose

truth value

depends

on evidence or information from outside itself

8
Q

What are sources used for supported statements?

A

Authority

Experience

Observation

9
Q

What are consistent statements?

A

Two statements

that can

both be true at the same time

10
Q

What are the four major relationships

with self-supporting statements

and supported statements?

A
  1. Consistency - true at the same time
  2. Implication - the first requires the truth of the second
  3. Logical equivalence - the first implies the second and the second implies the first
  4. Independence - Neither statement can imply the other
11
Q

What are the 3 types of disagreements?

A
  1. Real Disagreements - actual inconsistency: they can’t be true at the same time
  2. Apparent Disagreement - a difference of opinion
  3. Verbal Disagreement - a misunderstanding
12
Q

To analyze statements using categorical logic, translate them into a form that uses the ____________.

A

verb of being

13
Q

How do you change the verb of being to a predicate?

A
  1. Identify entire subject
  2. Choose the proper “to be” verb
  3. Rewrite the entire predicate as a predicate nominate.

NOTE: Maintain the tense of verbs (past, present, future) when translating statements to standard form.

14
Q

What are categorical statements?

A

Statements that

affirm** or **deny

something about a given subject

15
Q

What are the two parts of a statement?

A

Subject and Predicate

16
Q

The quantity identifies whether the statement is _______________ or ___________

and quality identifies whether a statement is ______________ or ________________.

A

universal (all and no) or particular (some)

affirmative** (all or some) or **negative (no and some…not)

17
Q

Identify their Quantity and Quality:

  1. All S are P
  2. No S are P
  3. Some S are P
  4. Some S are not P
A
  1. Universal / Affirmative
  2. Universal / Negative
  3. Particular/ Affirmative
  4. Particular/ Negative
18
Q

What is the Square of Opposition?

A

A diagram that demonstrates how

A, E, I and O

statements are related

19
Q

What are A statements?

A

All S are P

20
Q

What are E statements?

A

No S are not P

21
Q

What are I statements?

A

Some S are P

22
Q

What are O statements?

A

Some S are not P

23
Q

Which A, E, I, O statements are contradictory?

A

A contradicts O

E contradicts I

24
Q

Two statements are in _________________

if and only if

they always have opposite truth values

A

contradiction

25
Q

Two statements are ______________

if and only if

they can both be false but cannot both be true

A

contrary

26
Q

Contrary statements only exist

between _____ and ______ statements.

A

Universal A and E

27
Q

Subcontrariety is the relationship

that exists between ____ and ____ statements.

A

I and O

28
Q

Two statements are ______________

if and only if

both can be true but both cannot be false

A

subcontraries

29
Q

________________ is the relationship

between a universal and particular statement

of the same quality,

in which the truth of the universal necessitates the truth of the particular.

A

subimplication

30
Q

_______________ is the relationship

between a universal and particular statement

of the same quality,

in which the falsity of the particular necessitates the falsity of the universal

A

superimplication

31
Q

Subimplication can only exist

between pairs of ____ and ___ statements

and pairs of ___ and ___ statements

A

A and I

E and O

32
Q

Superimplication can only exist

between pairs of ___ and ___ statements

and pairs of ___ and ___ statements

A

I and A

O and E

33
Q
A