1.3a Valid
Arguments
Drag the description (in red)
to the appropriate argument below. (Place
them at the top left
of the argument -- they will "snap" into place over the white space.)
Valid, True Premises,
True Conclusion |
|
Valid,
False Premises,
True Conclusion |
| |
Invalid,
True Premises,
False Conclusion |
|
Valid,
False Premises,
False Conclusion |
|
Valid,
True Premises,
False Conclusion |
Good!
Notice that one can't tell that an argument is valid from the
actual truth or falsity of premises and conclusion.
One needs to know that the conclusion is not only true if the premises are true but that it must be true if the premises are true.
All
ravens are birds.
No birds are mammals.
_____________
No ravens are mammals.
Some
monkeys are human.
All humans have tails.
_____________
Some monkeys have tails.
All
whales are fish.
All fish fly.
_______
All whales fly.