Snapedom

I agree on the virtue of a self-preserving mentality, and on how "cunning" in the context of HP is a word applied to their tendency to get the job done, rather than just being passionate about it (Those cunning folk use any means to achieve their ends --PS/SS).

Another distinguishing character of the Slytherins IMO is their peer loyalty and sense of camaraderie. The Sorting hat sings "You'll make your real friends," and that word "real" there isn't put in without reason. Despite what we're led to assume (especially because of that word "cunning" being in there too) the friendships of the Slytherins are way more genuine than the ones found in the Gryffindor norm.

The Gryffindors tend to make friends when it serves them well. Harry was lonely, Hermione was anxious to assimilate into the WW, and they formed a bond on the train with Ron, who had been wishing all his life to escape the shadow of all his brilliant brothers. James and Sirius all but use the timid Peter and Remus as hangers-on and excuse-givers. And most important of all, the nuclear-shaped friendships of the Gryffindor House seldom seem to grow into a larger web of social interactions with a genuine feeling of closeness. They're capable of teamwork when it serves their needs. The personal caring, however, don't come naturally to them -- if it ever comes to them at all. Note Harry's reaction of *surprise* as he discovers the extent of Luna's caring for *all* of her friends... Harry is content with the trio bond that he needs and has, and all the other people around (even those he likes) are just there as an abstraction of "nice people" in his eyes, most of the time. The same kind of detachment is found in Lily (who could let Severus writhe on the ground while she chatted with James about the ethics of bullying), James and Sirius (who could even risk their "friend" Remus' life and sanctuary in first using him as an instrument of attempted murder and then letting the entire school know that James had saved Severus), and definitely in Dumbledore (whose callous behaviors toward fellow human beings are too numerous to name).

Contrast them with the Slytherin capacity for inclusive friendship. Snape's circle of Slytherin friends, despite what "Dark" and evil things they were doing, are large and welcoming towards new Slytherins (which was how Severus the greasy half-blood found himself in their midst in the first place) as well as loyal and faithful, as far as we get the sense from Sirius' comments and the argument between Severus and Lily. Regulus had the picture of the entire quidditch team in his post-Hogwarts bedroom. Not some token of their victory, but their *picture*. That's the team spirit of the Slytherin, the thing which other Houses shun as "cunning" and self-serving, because to them (especially to the Gryffindors) such a huge network of friendship can only be guessed as a means to a personal gain. And some Slytherins like Tom Jr. and Slughorn indeed take advantage of their friend-making abilities for their own benefit. But the majority of the Slytherins are people who genuinely care for peers whose strengths they admire, and whose weeknesses and hardships they truly sympathize with. Lucius the aristocrate places a hand on the poorly clothed Severus the moment he gets sorted into under his wings. Draco makes a heartfelt attempt to befriend Harry, the boy whose existence led to the defeat of Voldemort and almost got his father in jail, and whose family is notorious (from his POV) as an enemy of Dark Arts -- the thing he wanted to learn at Durmstrang instead of coming to Hogwarts. The Slytherin inclination for building strong and wide friendships is truly great, and it's a laudable quality -- if not in HP (possibly, maybe) then surely in my own view of the world.