Wikipedia has become one of the dominant pillars of the internet and a shining success of knowledge. And on Wikipedia, "Citation Needed" makes sense - because they're trying to build an encyclopedia with references.
Some people don't seem to get that the entire world isn't an encyclopedia.
When you're having a discussion somewhere online, replying to something you dislike with "Citation Needed" is usually counterproductive to good discussion.
Yes, sometimes citation is needed. Especially if something seems off. But here's some guidelines to not looking stupid when you're having a discussion -
1. Do at least one Google search before saying "citation needed" - if there's clear support on your first google search, it's a fact you don't know, not some craziness from your discussion opponent.
2. Ask yourself, "Am I only applying the citation scrutiny because I dislike the point the other person is making?" Citation-needed can be a pretty passive aggressive way to disagree. It implies that the person speaking doesn't know what they're talking about. But, even if that's the case, then...
3. The more polite thing to do is express why you're curious on sources. Something like, "My experience doesn't match that, is that really how it is?" Or, "I've read the opposite... do you have any stats on this?" Or, "That doesn't sound right. Do you have a cite?" That promotes discussion. Unless you really do think they're crazy, in which case...
4. Just grow a set of balls and disagree. If you think they're wrong, just say they're wrong. Maybe link to a source. Or just state your opinion.
"Citation Needed" says "Go spend 10 minutes getting me sources before I'll bother to engage you." If someone sounds totally wrong, just say you disagree and what the facts are. If you don't know, Google it. If you don't see anything, say that and then ask where they got their source.
This same thing applies to, "How can you say that without backing it up with facts?" and other variations. At least, at the very least, please do one google search. Your discussions will improve, and the internet will thank you.
Related to: Rationalists Should Win, Why Our Kind Can't Cooperate, Can Humanism Match Religion's Output?, Humans Are Not Automatically Strategic, Paul Graham's "Why Nerds Are Unpopular"
The "Prisoner's Dilemma" refers to a game theory problem developed in the 1950's. Two prisoners are taken and interrogated separately. If either of them confesses and betrays the other person - "defecting" - they'll receive a reduced sentence, and their partner will get a greater sentence. However, if both defect, then they'll both receive higher sentences than if neither of them confessed.
This brings the prisoner to a strange problem. The best solution individually is to defect. But if both take the individually best solution, then they'll be worst off overall. This has wide ranging implications for international relations, negotiation, politics, and many other fields.
Members of LessWrong are incredibly smart people who tend to like game theory, and debate and explore and try to understand problems like this. But, does knowing game theory actually make you more effective in real life?
I think the answer is yes, with a caveat - you need the basic social skills to implement your game theory solution. The worst-case scenario in an interrogation would be to "defect by accident" - meaning that you'd just blurt out something stupidly because you didn't think it through before speaking. This might result in you and your partner both receiving higher sentences... a very bad situation. Game theory doesn't take over until basic skill conditions are met, so that you could actually execute any plan you come up with.
Ah, yes, citing sources, the great bane of undergraduate students and the great headache of graduate students. When the stuff you write is based on other stuff, you need to cite. Most likely, your professor/department asks you to cite that stuff using the American Psychological Association (APA) citation style or the Modern Language Association (MLA) citation style. Your discipline may have its own citation style (e.g., American Political Science Association; American Anthropological Association). Whatever the style, it can be a headache for new and returning graduate students.
Why does citation give people so much trouble? I foresee two reasons why citation evokes such bad vibes.
Reference Pages Are No Longer the Big Concern
During my undergraduate career, it was the dreaded reference page (APA) and the Works Cited page (MLA) that was difficult. Remembering where to put the commas, the periods, the order of authors, the editors, yada yada made it an absolute nightmare to type out in hand.