If you are talking about strict logical arguments, the conclusion is implicit in the premises. That is the conclusion adds nothing - the argument simply brings out what is already there.
All valid logical arguments are tautologous.
And that is how premises support the conclusion.
Okay. Good. We now have established how premises support their conclusion, but how, then, do they prove their conclusion? I think they can only do this by being proven themselves, which requires something external, no?
If unproven, they still permit a valid argument, and therein lies the problem that I think we need evidence to solve. Without evidence, it seems, there is no way to actually find out whether a valid argument is also sound or whether it is simply just valid. Dr. A. gave a nice example:
Dr. A writes:
Premise 1: If I am an astronaut, then I have red hair.
Premise 2: I am an astronaut.
Conclusion: I have red hair.
This argument is valid and its premises support their conclusion; BUT, they do not prove it, or so it seems to me, because the premises are not proven true, and the argument thus unsound.
How do we prove premises true? Is this the purpose of evidence? If so, how does evidence prove premises true? We are satisfied, I think, with how premises support a conclusionyou laid that out very nicely, thank youbut we still get the problem that a valid argument can have an unproven conclusion if one of its premises is unproven, or correct me if I have erred.
Thank you,
Jon
[O]ur tiny half-kilogram rock just compeltely fucked up our starship. - Rahvin