I’ve noticed the same reaction. I’ve posted some comments that disagreed with others and I got downvoted – so it is really discouraging to disagree. I think that the solution here could be that next to karma there is courage section for people who are not afraid to disagree. There should also be something like “Karma Court” where respected guys from YC community decide if the post that got downvoted was plain stupid/disrespectful or just disagreeing. The members of Karma Court should bee respected fans of YC - motivation to become karma judges could be even bigger respect and recognition from other community members. What do you think of that?