Negs are ambiguous semi-insults invented to get the attention of hot girls, particularly at bars, clubs and parties. They function in part by making the girl a little insecure so she wants to gain your approval. They also show a lack of respect for her, which sets you apart from the people who drool over her; they show her that you are your own person and not trying to please her.
The hotter the girl, the more negs should be used. But you have to be very careful. If you use several on a girl who doesn't have an inflated ego, she will be crushed. And even the most stuck up, pretty girls are fragile and vulnerable underneath their exterior behaviors, so negs must be used sparringly.
If one wants to manipulate girls into having sex with you or dating you, and one intends to meet a fairly large number of girls, and wants to maximize how many of them he attracts, then negs are definitely an effective approach.
What if one wants to attract people who are not shallow into becoming one's friends? Then there is no particular reason to target the hottest girls (or people with status for another reason, e.g. from an old money family). And for people who aren't stuck up or otherwise being highly selective about who they pay attention to, negs aren't needed to gain some attention. Since there is no reason to expect the really hot girls to be smart, just leave them alone (in fact there are reasons to expect them to be dumb: they can go through life gaining approval and money without being smart, so have lessened incentive, and since most people consider thinking hard they won't do it a whole lot without incentive).
But what about people who have status for some substantial reason? Take Richard Dawkins as an example of someone who has achived some fame -- too much to be approachable by just anyone -- but he has achived it by being intelligent and one might want to befriend him due to his intelligence.
So, should one neg Dawkins, or similar other people? This assumes you are very smart and have good reason to believe they would like you, and be glad to know you, once you got to talking much.
Argument in favor of negging Dawkins:
It's an effective way to get attention very quickly, even in what would otherwise be a 60 second encounter (then one gains enough time to bring up intellectual stuff)
- it's manipulative
- it does bypass a some error correction -- it's taking Dawkins' attention without saying something that he would judge intellectually and might or might not actually find worthy
- the person might recognize it as a neg, or as manipulative, and dislike you (without ever hearing you say anything you consider intelligent -- so supposing he *would* want to talk with you if he heard some of your ideas, now you've both missed out)
- where is your optimism? don't you think there are thoroughly good ways to interact with people?
Further arguments in favor:
There exist social customs, like ice breakers, and just because someone is intelligent doesn't mean strangers can just ignore all custom and they won't mind. But if you obey the customs they use up time and give Dawkins no reason to stay longer. (I have no idea how conventionally minded Dawkins is, but no doubt there are some smart people who are.)
The optimism argument is mistaken. Of course it's possible to find a way to say something substantive while obeying all the customs and being extremely charming. But that's hard. It's much harder than negging. Why should one expend a huge amount of effort when negging is effective? There are plenty of good things to do in life; using time solving a problem that already has an effective solution comes at the cost of less effort towards unsolved problems. It could easily be the case that the amount of effort it would take to be both charming and substantive is so much, compared to the benefit of becoming frineds with Dawkins, that one doesn't consider it a worthwhile project to undertake.
It reduces error correction but it's effective and saves human effort which is important. Error correction is worth the effort in general, but there's no direct, efficient way to achieve it here, and error correction will still take place just delayed some.
Therefore, it's good to neg Richard Dawkins and others if one has a good enough reason to want their attention. (Yeah, I know this is one of those things where everyone will thoughtlessly think their reason is good enough when it isn't. But the prevelance of that mistake doesn't change the correct conclusion.)
If you're still skeptical, consider this: if he understood these issues, and wanted to be available in more substantive ways so no one would have any reason to neg him, he could do something about it. He could put creativity into creating ways for worthwhile ideas to contact him (and communicating to people that they exist and are genuinely different than the ineffective contact options some famous people use). He hasn't done that.