1.
|
Can
one tell whether an argument is valid or not from the following information? |
|
(i)
|
Its
premises are true and its conclusion true. |
|
(ii)
|
Its
premises are true and its conclusion is false. |
|
(iii)
|
At
least one of its premises is false and its conclusion is true. |
|
(iv)
|
At
least one of its premises is false and its conclusion is false.
|
2.
|
Can
one have an invalid argument which meets the following conditions?
|
|
(i)
|
Its
premises are consistent with its conclusion? |
|
(ii)
|
Its
premises are inconsistent and its conclusion is false. |
|
(iii)
|
Its
premises is a necessary truth and its conclusion is true. |
3.
|
Can
one have a valid argument which meets the following conditions? |
|
(i)
|
Its premises are consistent but its conclusion is false. |
|
(ii)
|
Its
conclusion is inconsistent with the premises. |
|
(iii)
|
Its
conclusion is inconsistent with the premises, and the premises are
consistent. |
|
(iv)
|
The
negation of its conclusion is consistent with one of the premises. |
|
(v)
|
The
negation of its conclusion is inconsistent with the negation of one
of the premises. |
|
(vi)
|
The
negation of its conclusion is inconsistent with the negation of one
of the premises, and the argument would not be valid without this
premise. |