An ARGUMENT is
a set of propositions such that the truth of one (called "the conclusion") is supposed to be supported by the truth of the others (called "the premises")
An argument is DEDUCTIVE
if and only if it supposes that if the premises of the argument were true, then its conclusion would have to be true.
A deductive argument is VALID
a) if and only if it is impossible for the premises to be true and conclusion falseb) if the premises of the argument were true, then the conclusion would have to be true
A deductive argument is INVALID
if and only if it is possible for the premises to be true and the conclusion false
A deductive argument is SOUND
if and only if it is both valid and all its premises are actually true
A deductive argument is UNSOUND
if and only if it is either invalid or has at least one false premise
An argument is INDUCTIVE
if and only if its conclusion is supposed to be made more likely to be true than to be false given the truth of its premises(suppose that if the premises were true then the conclusion would be more likely to be true than to be false)
An inductive argument is STRONG
if and only if were the premises true, the conclusion would be more likely to be true than to be false
An inductive argument is WEAK
if and only if, if the premises were true the conclusion would be less likely (or no more likely) to be true than to be false
An inductive argument is GOOD
if and only if it is both strong and all its premises are actually true
An inductive argument is BAD
if and only if it is either weak or has at least one false premise
What is the smallest number of propositions that can make up an argument? Why?
2, because one is the premise, and one is the conclusion being supported by the premise
A PREMISE is
a proposition whose truth is supposed to give support to the truth of the conclusion
A CONCLUSION is
a proposition in an argument whose truth is supposed to be supported by the truth of the premises
What are the 2 standards for evaluating arguments?
a) Do the premises support the conclusion?b) Are the premises all actually true?