Posted: Nov 29, 2017 11:58 am
zulumoose wrote:Looks like you are both confusing each other.
An argument is sound if it follows from the premises, whether the premises are true or not. He is correct there.
No, what you're describing is validity.
The argument ITSELF is sound, the conclusion may not be valid.
No, an argument is sound if it is valid (conclusion logically follows from the premises) and the premises are true.
https://en.wikipedia.org/wiki/Soundness#Validation_vs._soundness
Either way, the discusssion is about his argument that the premises don't have to be demonstrably true, just true.
Which begs the question: how do you know the premises are true if you cannot demonstrate them to be so?