Of Arguments
An argument is sound if and only if
- The argument is valid.
- All of its premises are true.
For instance,
- All men are mortal.
- Socrates is a man.
- Therefore, Socrates is mortal.
The argument is valid (because the conclusion is true based on the premises, that is, that the conclusion follows the premises) and since the premises are in fact true, the argument is sound.
The following argument is valid but not sound:
- All organisms with wings can fly.
- Penguins have wings.
- Therefore, penguins can fly.
Since the first premise is actually false, the argument, though valid, is not sound.
Read more about this topic: Soundness
Famous quotes containing the word arguments:
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—Roger Bacon (c. 1214–1294)