Compound Claims

Df.  A compound claim is composed of other claims, but has to be viewed as just one claim

Types of compound claims

Df.  Contradictory of a claim is a statement that always has opposite truth value

Excluding Possibilities (Disjunctive Syllogism) and False Dilemma

Valid Reasoning with Conditionals

Invalid (Usually Weak) Reasoning with Conditionals

Difference between If and Only If

Reasoning in a Chain



Direct Way of Refuting Arguments

Indirect Way of Refuting Arguments

Bad Attempts at Refuting Arguments


General Claims

Issue:  We need to know how to reason with claims that are asserted about

all, or some, or a few, or no things

Use of Quantifiers and Inclusion versus Exclusion

Some Valid Types of Universal Reasoning

Some Invalid (Weak) Types of Reasoning from Universals and Particulars

Arguments Using Almost All and Very Few