Introductory Logic, Lessons 1-23

Define Your Terms

100

Drawing proper conclusions from other information

Reasoning

200

This definition seeks to influence the attitudes or emotions of an audience.

Persuasive

300

The three basic ways to define terms.

Example, synonym, genus & difference

400

A sentence with a truth value.

A statement

500

This is an actual inconsistency between two statements.

A real disagreement

Statements

100

This is the law that states that all statements are either true or false.

The Law of Identity

200

This is an example of a non-statement.

Question, command or nonsense

300

Another name for a statement that is always true by logical structure.

A tautology

400

This is a statement whose truth value depends upon evidence or information from outside itself.

A supported statement

500

This kind of statement either affirms or denies something about a given subject.

A categorical statement

Relationships

100

This relationship states that both statements can be true at the same time.

Consistency

200

Two statements that imply each other are related this way.

Logical equivalence

300

This is the relationship between two statements where the truth of one necessitates the truth of the other.

Implication

400

This is an actual inconsistency between two statements.

A real disagreement

500

What is the best method to use to determine if this statement is true or not, "The leaning tower will fall down." 

Deduction

The Square of Opposition

100

The "A" statement is written this way in standard form.

All S is P.

200

This is the particular negative statement.

O: Some S is not P.

300

If "All astronauts are men" is false, what does that tell us about "No astronauts are men"? 

We don't know the statement's truth value.

400

Two statements are related by _________ if and only if both can be true but both cannot be false.

Subcontrariety

500

This is the positive or negative nature of its claim about the subject 

The quality of a statement

Miscellaneous

100

These are the three errors to avoid when creating genus and species definitions.

Overlapping 

200

This is the sum of the common attributes of a term.

Intension

300

These are the three errors to avoid when creating genus and species definitions.

Overlapping species, ambiguous terms, using parts of a term not the whole term

400

What hymn writer and logician identified and described six methods "whereby truth is let into the mind." (Page 66)

Isaac Watts

500

In his book, "Prior Analytics" this author introduced key terms such as syllogism, premise, major, minor, & middle terms. (Page 146)

Aristotle