James Surowiecki, a writer at the famous New Yorker magazine, was the first to highlight how people power can work together on the internet. James showed how groups of diverse people acting independently are smarter than any one person in the group.

The 4 conditions that characterize wise crowds:
1. Diversity of opinion
2. Independence
3. Decentralization
4. Aggregation

The Wisdom of Crowds is not an argument against experts, but against our excessive faith in the single individual decision maker.
You do not need consensus in order to tap into the wisdom of a crowd. The search for consensus encourages tepid lowest-common-denominator solutions which offend no one rather than exciting everyone.
Grouping only smart people together doesn't work that well, because the smart people tend to resemble eachother in what they can do. The group knows less than it otherwise might. Adding in a few people who know less, but have different skills, actually improves the group's performance.
The more influence a group's members exert on eachother, and the more personal contact they have with eachother, the less likely it is that the group's decisions will be wise ones. We could become individually smarter but collectively dumber.
Groups that are too much alike find it harder to keep learning, because each member is bringing less and less to the table. They spend too much time exploiting, and not enough time exploring.
A large group of diverse individuals will come up with better and more robust forecasts and make more intelligent decisions than even the most skilled "decision maker".
Seer-sucker theory: No matter how much evidence exists that seers do not exist, suckers will pay for the existence of seers.
Encouraging people to make incorrect guesses actually made the group as a whole smarter.
One key to successful group decisions is getting people to pay much less attention to what everyone else is saying.
The closer a person is to a problem, the more likely he or she is to have a good solution to it.
The foundation of cooperation is not really trust, but the durability of the relationship. Whether the players trust eachother or not is less important in the long run than whether the conditions are ripe for them to build a stable pattern of cooperation with eachother.
Successful cooperation requires that people start off by being nice, willing to cooperate, but have to be willing to punish noncooperative behavior as soon as it appears. The best approach is to be "nice, forgiving, and retailiatory".
The more responsibilty people have for their own environments the more engaged they will be.
The idea of the wisdom of crowds is not that a group will always give you the right answer, but that on average it will consistently come up with a better answer than any individual could provide. That's why the fact that only a fraction of investors consistently do better than the market remains the most powerful piece of evidence that the market is efficient.
The healthiest markets are those that are animated by both fear and greed at the same time. Any time you sell a stock, the person who's buying it thinks differently about the future prospects of that stock. You think it's going down, he thinks it's going up. One of you will be right, but the important thing is that it's only through the interaction of those differing attitudes that the market is able to do a good job of allocating capital.
News reporters tend to overplay the importance of any particular piece of information. The best way to disclose public information is without hype or commentary from people in the positions of power. (Like the way the Federal Reserve announces its interest-rate hikes.)
Government kept getting bigger, since everyone had an individual interest in getting a little more from the state, and no one was looking out for the collective interest, entered into cozy arrangements with the businesses it was regulating, and that allowed economic policy to be run in the interests of powerful groups instead of the interests of the public as a whole.

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