Intro Flashcards
What is philosophy?
Philosophy is a tradition of posing and attempting to answer questions that we do not know how to answer within
the empirical sciences.
What is an Argument?
An argument is a set of statements, containing one or more premise and typically one conclusion.
• The purpose of an argument is to convince someone to accept that a statement (the conclusion) is
true.
• The idea is that if someone accepts that the premises are true, then they have to accept that the
conclusion is true.
– Why? It would be irrational to fail to accept the conclusion if one accepts the premises.
It’s often helpful to list the premise(s) and conclusion of an argument explicitly.
• This helps us see whether the argument is any good; i.e. whether we should accept the conclusion.
The standard format for such arguments is something like this:
Argument 1:
1. First premise
2. Second premise
. . .
3. Conclusion
Argument 2
1. Auburn is in Alabama
2. Alabama is in the United States
3. Auburn is in the United States
Validity
A valid argument is one in which the conclusion follows the premises. Both the conclusion and the premises can be false
Examples:
Valid Arg 1:
1. Auburn is in Mississippi
2. Mississippi is in California
3. Auburn is in California
Valid Arg 2
1. Auburn is a university
2. No university is in Alabama
3. Auburn is not in Alabama
“That follows” What does it mean for a conclusion to follow from some premises? There are two ways
to think about this relation:
• If you accept the premises, you must accept the conclusion. (It would be irrational to accept the
premises and not to accept the conclusion.)
• It’s impossible for the premises to be true and the conclusion to be false (at the same time). Or,
equivalently, if the premises are true, the conclusion must be true.
– Here, we are talking about impossibility and necessity in the strongest sense: there could not be
a world where the premises are true and the conclusion is false.
Soundness
A sound argument is valid, and all of its premises are true.
• The conclusion of a sound argument must be true.
• A sound argument is a good argument: it should serve its purpose of convincing an interlocutor that
a conclusion is true. (As long as the interlocutor agrees that the argument is sound!)
Sound arg
1. Ivey is governor
2. Only one person can be governor
3. Zach isn’t governor
Unsound arg
1. Zach is governor
2. Only one person can be the governor
3. Bruce Pearl isn’t governor
• Unsound Arg is valid, and the conclusion is true, but premise 1 is false.
Excercises
Construct:
• An invalid argument with true premises and a true conclusion.
• A valid argument with a false conclusion.
A sound argument.
• A valid argument for the conclusion that it is wrong to steal.
• A valid argument for the conclusion that it is not wrong to steal.
