Introduction to Arguments Flashcards
What is logic?
The study of the methods used to evaluate arguments.
What is an argument?
A set of statements where one of those statements (the conclusion) is affirmed on the basis of the others (the premises).
A statement
A statement is any sentence that is either true or false; statements are the building blocks of arguments.
Premise indicators
Words or phrases indicating that what comes immediately after them is a premise on the basis of which a conclusion is affirmed.
Conclusion indicators
Words or phrases indicating that what comes immediately after them is a conclusion affirmed on the basis of premises supplied elsewhere in the argument.
A report
A report is a set of statements where none of the statements is affirmed on the basis of the others AND where the statements are offered for the purpose of simply providing the reader with information.
A mere conditional statement
A mere conditional statement is an “if … then” statement that is NOT used to either affirm or deny either of its component clauses.
What makes a conditional statement a MERE conditional statement is that it is not used to affirm or deny either of the clauses that compose it.
An illustration
An illustration is a set of statements where none of the statements is affirmed on the basis of the others, AND where one of the statements is explained or clarified through the use of an example.
The purpose of the illustration is not to defend the first statement or argue that it is true but to simply provide an example of it.
An explanation
An explanation is a set of statements where none of the statements is affirmed on the basis of the others AND where some of the statements tell the reader why one of the other statements is true.
A valid argument
A valid argument is an argument in which the truth of the premises absolutely guarantees the truth of the conclusion - an argument in which it is not possible for the premises to be true and the conclusion false.
An invalid argument
An invalid argument is an argument in which the truth of the premises does not absolutely guarantee the truth of the conclusion - an argument in which it is possible for the premises to be true and the conclusion false.
A sound argument
A sound argument is a valid argument with only true premises.
An unsound argument
An unsound argument is an argument that is not sound.
Deductive logic
Deductive logic is the study of the methods used to evaluate arguments for validity or invalidity.
A strong argument
A strong argument is an argument in which the truth of the premises makes the conclusion more likely than not, without absolutely guaranteeing the conclusion.
A weak argument
A weak argument is an argument in which the truth of the premises does not make the truth of the conclusion more likely than not.
A cogent argument
A cogent argument is a strong argument with ONLY true premises.
An uncogent argument
An uncogent argument is an argument that is not cogent; it is either a weak argument or an argument that is strong but has at least one false premise.
Inductive logic
Inductive logic is the study of the methods used to evaluate arguments for strength or weakness.
Knowledge of statements
It is not required that a statement be KNOWN to be true or false, but only that it can be either true or false.
NB: any sentence that is neither true or false is not a ‘statement’ for argument purposes.
Requirements for arguments
An argument needs at least two statements, and one of them needs to be affirmed on the basis of the others; the others need to be offered as reasons for for believing the statement.
Arguments of only one sentence?
Strictly speaking, a statement doesn’t need to be a sentence, but can be a clause that COULD function on its own as a sentence that is either true or false.
E.g, a sentence with at least two clauses that can function alone as sentences that are either true or false, and one of them is affirmed on the basis of the other.
When is a passage NOT an argument?
Where a passage is composed of sets of statements, but the statements are not related to one another in the right way to form arguments, because NONE of the statements is affirmed on the basis of the others.
Common ‘passages’ that are not arguments (x4)
- Report
- Mere Conditional Statement
- Illustration
- Explanation