A) Downvote the comment because the I think the conclusions are grossly wrong.
B) Upvote the comment because I'm so enamored of the elegance of the argument, it's contribution to the conversation, and how it made me think more carefully about my own argument.
C) Ignore it - and unjustly not provide my reasoned critique on what clearly took a great deal of effort by the author.
If I could only Flag it as "DISAGREE WITH CONCLUSION" and "ADDS TO CONVERSATION" then everything would be good.
The four flags that I think would be useful would be:
FLUFF vs CONTRIBUTES
AGREE vs DISAGREE
SPAM
INCIVIL
That way, I can now simultaneously rank an article as both contributing, as well as disagreeing with the conclusion.An author may then write an unpopular, but carefully reasoned discourse, and still enjoy the positive feedback of his peers on his contribution, even if he is challenging their perspectives.