Fallacy Theory Evaluating Arguments
Formal Fallacy (Structure Flaw) Affirming the Consequent: if A then B, B, thus A invalid version of Modus Ponens (affirming the antecedent) Courtney will go to the movie only if she finishes her homework. She fini
RULES OF INFERENCE: Rules that can be used to derive
either a conclusion directly or a series of intermediate conclusions that link the
premises of an argument with the stated conclusion
Rules of Implication:First 8 rules of inference. They are simple, va
*All of these are informal fallacies
Fallacy/Fallacy
Type
Definition
Example
These fallacies share the common characteristic
that the arguments in which they occur have
premises that are logically irrelevant to the
conclusion.

Appeal to Force
Occurs whe
2. Derivation Tips for Predicate Logic
(1)
A common mistake I saw on the fourth exam (on predicate logic):
Applying the instantiation & generalization rules to p
arts of a statement.
Recall that the instantiation rules and generalization rules are rules