When I was a student of software engineering, I felt strongly that there was not enough emphasis given to what effect the use of computers has on humans, and what sort of software we ought to make to benefit humans. This is related to Tim O'Reilly's call to "Work on Stuff that Matters" (http://radar.oreilly.com/2009/01/work-on-stuff-that-matters-...). It's not about the machine or the money -- we must add value to people's lives.
This is a different issue than that of being kind to each other on Hacker News, but I happen to think it is deeply related.
In some circumstances, I am spontaneous, playful, and extremely open to my environment and aware of other people. When I spend a lot of time programming, however, I tend to become more cautious, analytical, and insensitive. Partly this is because any time spent programming is, generally speaking, spent away from people and in ignorance of our bodies (and hence, our environments). This is one reason why I think it is so important for engineers to have diverse interests.
It's not just so that we will be kinder to each other on Hacker News. We are, in a very significant way, the people building the future. We need to make sure that we are in the right frame of mind to build a future we want to live in, and not one that is anti-social and inhumane.
Perhaps the reason dystopian sci-fi has so much resonance is because we are already experiencing, unconsciously, the dehumanizing effects of technology.