In: Advanced Math
SYMBOLIC LOGIC QUESTION:
Recall that a valid argument is one in which it is impossible for the conclusion to be false, if the premises are true. Explain how, in this context, the Negation Introduction rule demonstrates the concept of validity.
A valid argument is one where premises necessarily lead to the conclusion.
All elephant can fly, Dumbo is an elephant, therefore, Dumbo can fly. This is a valid argument.
The problem with many arguments is that they are apparently valid on their face and therefore people assume they are true. And sometimes it can be very difficult to figure out if the premises are actually true, or whether they are true in all possible cases.
All swans are white, Black swans are swans, Therefore, black swans are white.
Since everybody knew that all swans are white because of the only swans ever observed were white. But just because nobody had ever seen a black swan before didn't mean there weren't any.
If we had two argument P and Q, and R is the conclusion.
P | Q | R |
T | T | T |