I don't care much about karma. But, I do care about having the freedom to post stuff that I find interesting. Now, I am assuming that most of the noise will be

I don't care much about karma. But, I do care about having the freedom to post stuff that I find interesting. Now, I am assuming that most of the noise will be either from new members or from members with low karma. If they are penalized something like 5 karma for submissions (and they can't submit if they don't have 5 karma), then that will both passively and actively discourage spamming. A karma threshold can also be applied to new users to encourage them to first participate int he discussion and understand the ethos of HN. Edit: I want to clarify that I am in favour of deducting karma for new submissions. The comment system is already fairly balanced thanks to the option to downvote. What I am suggesting is essentially a mirror image of the parent article.