The burden of proof in arguments

[Raistlin]

I suppose where he is coming from with this is if you are having a discussion about... I don't know, the effects of gun control? If I provide evidence that gun control reduces crime, you might still produce a study which demonstrates different consequences.

Actually no, I suppose both claims there are positive ones and so proof is required by either side anyway...

I love it when people correct themselves. Saves me the trouble!

You made a good point, though, that the line is also not as clear-cut when you're discussing correlation and causation (e.g., there may be a study to show there is no link between X and Y). However, in such cases "no link" is in fact a positive assertion (the difference between "I don't believe in god" and "I believe there is no god"). Still, even in those cases the only evidence the study is using is absence of evidence.