As gloob figured out, it was primarily a joke, though I find your vehement disgust with my use of a Star Wars quote to be a bit disturbing. Besides, sci-fi nerds generally read a lot so the library bit doesn't even make sense... and who wouldn't want to own a light saber (though I can't say it's something I actively daydream about)?
However, in defense of my statement, 4chan is the only place I've ever seen photos of a nude, decapitated woman posed in sexually suggestive positions, and it would probably take you 5 minutes of browsing /b/ to find drawings of girls under the age of 10 having sex.
But they didn't take those pictures, or kill the woman. They didn't even know them, or much about them probably. They found a picture on the internet, and they posted that same picture to another part of the internet. Truly moral outrage should ensue.
Since you are a sci-fi fan, here is a sci-fi reference.
Neo takes the blue pill. He finds out what the 'real' reality is, behind the bullshit fabricated reality. The stuff about the dead lady? That actually happened. Stuff far worse happens every day. If that makes you uncomfortable, or outraged, or whatever negative emotion you are expressing, you are just angry at reality. Don't blame 4chan.
I'm reasonably sure you are the person closest to being outraged about anything in this discussion, heh. He was being funny, not raving about how 4chan is the root cause of all evil. And in any case, the fact that actively evil people exist independent of 4chan is orthogonal to whether the site is legitimately "a hive of scum and villainy."
However, in defense of my statement, 4chan is the only place I've ever seen photos of a nude, decapitated woman posed in sexually suggestive positions, and it would probably take you 5 minutes of browsing /b/ to find drawings of girls under the age of 10 having sex.
(edit: typo)