Term | Definition |
Logic | Organized body of knowledge that evaluates arguments |
Argument | A line of reasoning compsed of statements called premises offered in support of another statement, called the conclusion. |
Premises | statements that set forth reasons or evidence in an attempt to support a conclusion |
Statement | sentence that is either true or false |
Conclusion | Statement that evidence is claimed to support or imply ; statement that is claimed to follow premises |
Conditional Statement | An ïf... then..." statement; an assertion that if if the antecedent is true, then so is the consequent |
Deductive Argument | Aims to prove a conclusion with absolute certainty |
Inductive Argument | Aims to prove a conclusion beyond resonable doubt |
Valid | A deductive argument who's premises fit the conclusion; i.e. if the premises are true, the conclusion must be true |
Invalid | A deductive |
Sound | A deductive argument that is valid and has true premises |
Unsound | A deductive argument that is valid but has false premises |
Strong | An inductive argument who's premises fit the conclusion; i.e. if the premises are true, the conclusion must be true |
Weak | An inductive argument that is structurally unsound. The premises do not fit the conclusion. |
Cogent | An inductive argument that is strong and has true premises |
Uncogent | An inductive argument that is strong but does not have true premises |
Syllogism | Line of reasoning made up of 2 premises and a conclusion |
Counterexample | A method for
proving invalidity; consists of constructing
a substitution instance having
true premises and false
conclusion |
Vertical Pattern | The premise directly supports the conclusion; a conclusion of a logically prior argument
becomes a premise of a subsequent argument |
Horizontal Pattern | Multiple premises lead to one conclusion; these premises do not rely or relate to each other |
Conjoint | the premises depend on one another
in such a way that if one were omitted, the support that the others provide would
be diminished or destroyed. Often use if/then statements |
Multiple Conclusion | One premise leading to multiple conclusions |