Final Exam Flashcards
The kinds of sentences that are of interest as premises or conclusions in logic must be
Evaluable as true or false
In a good deductive argument, the truth of the conclusion is ______ by the truth of the premises, whereas in a good inductive argument the truth of the conclusion is _______ by the truth of the premises
Guaranteed or entailed (first blank) and Made likely or probable (Second blank)
If an argument is valid, then it is best classified as
Deductive
If an argument is sound, what else can you infer about it
It is valid
If all that you know about an argument is that its premises are ALL true and its conclusion is false, what can you conclude about its validity
It is invalid
Being a reasonable human is a necessary condition for being a mammal (T/F)
False
Being a square is a sufficient condition for being a shape (T/F)
True
Being an animal is a necessary condition for being a cat. It is also sufficient (T/F)
False
Being a piece of aged cheddar is necessary but not sufficient for being a cheese (T/F)
False
An argument being valid is sufficient for it to be sound (T/F)`
False
An argument being sound is sufficient for it being valid (T/F)
True
An argument being valid is sufficient for it to have at least one true premise (T/F)
False
An argument having ALL true premises and a false conclusion is sufficient for it being invalid
True
Being a cheese is a necessary but a sufficient condition for being a dairy product (T/F)
False
Being a dog is a necessary but not sufficient condition for being a poodle (T/F)
True
Being a quadrilateral is sufficient for being a shape. Being a shape is a ______ condition for being a quadrilateral
Sufficient
Being a copy of the play Hamlet is both necessary and sufficient for being a copy of a play originally written by William Shakespeare (T/F)
False
In order to be president of the US it is _______ for a qualified person to win a majority of the Electoral College votes
Necessary
If a statement P “logically implies” a statement Q, then
If P is true, then Q must be true as well
Every true proposition logically implies only true premises (T/F)
True
A false proposition can logically imply both other false propositions and other propositions that are true (T/F)
True
An argument is valid if
The conclusion is logically implied by the premise(s)
An argument is sound just in the case that it is
Valid and has all true premises
If you only know that na argument has all false premises and it is valid, what can you conclude about the conclusion
The conclusion must be true
If you know that an argument has all true premises and a false conclusion, what can you conclude about this argument
The argument is invalid
In order for an argument to be valid it is sufficient for its premises to logically imply its conclusion (T/F)
True
In order for an argument to be valid, it is necessary for its premises to logically imply its conclusion (T/F)
True
Any two arguments having the same logical form are
Either both valid or both invalid
If you are unsure whether argument ‘A’ is valid or invalid, but you know of an argument ‘B’ that has the same logical form and has all true premises and a false conclusion, what can you conclude about argument ‘A’
Argument ‘A’ is invalid
In order for a term to be ambiguous it is necessary and sufficient for
It to have two or more normal meanings
In order for a term to be vague it is necessary and sufficient for
Its extension to admit borderline cases
In logical theory the syntax is
The grammar and symbols of the language
In logical theory the semantics is
The meaning or truth conditions of the language
In a truth table, an argument is valid if _______, and what tell us is that ______
There is no row where the premises are all true and the conclusion is false (first blank) and It is impossible for the premises to all be true and the conclusion be false (second blank)
