1.
|
Which
of the following are truth functors? Where the expression is a truth-functor,
what is its truth-table? Where it is not a truth-functor what is its
partial truth-table? (A partial truth-table is a truth-table in which
some rows have a "?" in them; in these cases, think of pairs
of examples to show that sometimes the resulting sentence will be
true in these cases and sometimes the resulting sentence will be false.) |
| |
(i)
|
j
or y or both. |
| |
(ii) |
It
is true that j |
| |
(iii)
|
It
is a necessary truth that j |
| |
(iv)
|
It
could have been the case that j |
| |
(v)
|
j,
but not because y
|
| |
(vi)
|
It
is true that j or it isn't |
| |
(vii) |
j,
but grass is not green |
| |
(viii) |
j,
whether or not grass is green |
| |
(ix)
|
Everyone
knows that it is true that j or it isn't |
