I know pg said that it's ok, but as my own personal rule, I've decided to go against this. I'm using the downvote only when somebody is actually wrong about something, not simply because I disagree with him/her.
The reason for this is because, even though I might disagree with somebody regarding a certain topic, I may very well learn something new from this person, and, why not, even change my previous views on the subject. In that case, his comment was valuable and helpful, and in my opinion, should be displayed even more prominently instead of being downvoted.
EDIT: One more thing occured to me just now: The reason why upvoting/downvoting shouldn't be used to express agreement/disagreement is because it promotes writing comments that appeal to the general public, disregarding if they are actually right or not. This leads to writing comments that you know people will like, which makes commenting on some topic a sort of a popularity contest. In the end, we will have lots of comments that say what we want to hear, not what we (maybe) should hear.
Perhaps I didn't phrase this as best as I could right now but hopefully the message got through.
I agree. Voting should be based on the quality of the contribution, not how closely it aligns with your own views.
Exceptions should be made when someone is presenting provably false information, but then a reply with counter-evidence is always preferable to a downvote. Downvoting without a reply is IMO only really appropriate for content-free comments that add nothing.
For instance, this is the perfect case for downvote. I strongly agree with the content - individual opinions here are mostly irrelevant - pg is the benevolent dictator and his opinions matter, not ours and he stated already that downvoting as a sign of disagreement is OK.
However, I prefer to disagree adding to the discussion.
I am downvoting you not because I disagree with you but because your statement was somewhat troll-ish. Don't take it personally. We should be nice to each other and disagree in a civil way.
Hey no problem. I agree that the idea is to keep the discussion civil. I didn't mean for my statement to be troll-ish but I can see how it could be seen that way. But the downvote doesn't matter to me personally. I sprinkle up and down votes liberally as the mood strikes and I expect others to do the same. I don't think one needs to deeply think about each vote.
I disagree with the Edit. People are free to vote comments up and down (with sufficient karma) for any reason whatsoever, and that is a good thing, i.e. downvoting a comment with which one disagrees is often healthier for the community than arguing a partisan issue (e.g. Erlang v Scala, Jobs v Gates, Briefs v Boxers) or repeating a counter-position described elsewhere.
