Emergent properties

How well groups of humans make decisions depends on how their members share information and form opinions. In this regard, there are two opposing ideas: the wisdom of crowds versus popular delusions and the madness of crowds. As a collective, we know far more than any individual, but collectives can also act more stupidly than most individuals would alone. And you can more easily reason with individuals than with groups. That is because shared beliefs hold a group together and define its identity. Hence, groups are likelier to stick to their beliefs than individuals when confronted with evidence that they are wrong. If some people defect, it causes mayhem that enemies can exploit.

And so, groups know more, but are also less rational than most of their members would be on their own. As the number of individuals in a group increases, their knowledge increases while their wisdom decreases. We are like that because it allows our genes to survive and spread. We are social animals, so we cooperate in groups, and to do that, we need to agree on a set of beliefs to act as a group, like going to war, and agreement rather than correctness of our beliefs usually is the decisive factor. So, if Christians and Muslims go on a holy war against each other, questioning their faith can be fatal.

Now, how can the intelligence of a group not be merely the sum of its members? How can the IQ of all individual humans sum up to 8 trillion, while the resulting IQ of all humanity might be 0? That is quite an interesting phenomenon. Groups have what the experts call ’emergent properties’. These are properties that emerge only at the group level once individuals form a group. These properties seemingly appear out of nowhere. An individual water molecule can’t generate a wave, but billions of water molecules in a lake can. One cell doesn’t make a horse or a rabbit, but billions of cells do.

A group of starlings can fly in intriguing patterns, which a single starling can’t. A single neuron can’t produce awareness. These properties emerge from the properties of the individuals. Individuals have properties that determine what they can do in groups, so a group of starlings can fly in intriguing patterns, while a group of humans can’t. And a group of water molecules can’t form a rabbit, even if they tried very hard, and despite a rabbit mostly consisting of water molecules. Luckily, water molecules don’t have ambitions, so they don’t have problems, and not being able to form a rabbit doesn’t trouble them.

Collective intelligence

Collectives cooperate and achieve much more than individuals. And they can process more information, which the experts call collective intelligence. Their strength lies in their cooperation and knowledge sharing. Bees and ants demonstrate collective intelligence. They share information about where to find food and use it collectively. Bees build beehives using a sophisticated division of labour, while ants can collectively defeat enemies many times their size.¹ It is a natural behaviour of bees and ants.

Ants also demonstrate what can go wrong with collective intelligence. They follow each other’s trails. If an ant accidentally walks in a circle, an entire colony might follow it. They could end up walking in circles until they die. In this case, otherwise beneficial behaviour goes wrong with fatal consequences. That is collective stupidity.¹ We cooperate based on shared beliefs, which can be incorrect. Usually, our beliefs are beneficial. They strengthen the group’s cohesion, which is often more crucial to our survival than being right.

Groups know more and perform better on quiz questions than individuals because they can share knowledge. In 1906, an Englishman named Francis Galton discovered a phenomenon, later dubbed the ‘wisdom of crowds’. Galton visited a livestock fair where an ox was on display. In a contest, the villagers estimated the animal’s weight. Nearly 800 people participated. No one guessed the weight of 1,198 pounds, but the average of the estimates was 1,207 pounds, thus less than 1% off the mark.

Galton concluded that the finding suggests that democracy is the best form of government. Taking every view into account in Parliament could result in the best possible decisions. At the fair, the contestants independently assessed the ox’s weight. They didn’t arrive at their estimate in a group process, which may explain why it worked so well.² The term ‘wisdom of crowds’ is deceptive because it is the aggregate estimate of independently thinking individuals, and not the outcome of a group process. Socrates would have agreed. Humans aren’t wise. It didn’t help us in the struggle for survival. And so, Socrates was executed.

No wisdom of crowds

There is no wisdom of crowds, but the stupidity of groups does exist. A Jew can make peace with a Palestinian, but the Jews and the Palestinians as peoples have failed to do so. Groups have collective intelligence, so they can process more information than individuals and are better at murdering than individuals. That is the advantage of operating in groups. Yet, to act as a collective, we must align our views, so that the collective intelligence can also disappear. Humans are social animals rather than rational beings.

We are prone to moral panics, which reduce our ability to think critically. A moral panic is a widespread feeling that some evil person or group schemes against our interests and well-being. Often, genuine concerns cause these feelings, but the claims often exaggerate the seriousness, extent, and certainty of the harm. That promotes group cohesion and generates collective action to remove the perceived threat. For our genes, it is better to be safe than sorry, and murdering others creates room for our genes to spread.

Crowds can make better estimates in aggregate, but only if their members don’t influence each other. As long as we retain an independent perspective, we can’t develop groupthink. When we influence each other, we can go collectively crazy. We seek our peers’ approval, which clouds our judgment. We are social animals who need the group to survive, so we share our group’s beliefs and don’t openly disagree. We may even share ideas we know are incorrect, so we ignore our knowledge and pass on the group’s views for the good of the cause.

Herd behaviour

Information often spreads through herd behaviour. We usually behave the same way.¹ YouTube makes use of it. If you come across a video with ten million views, you are more likely to watch it than one with only ten views. Usually, videos with ten views are not worth watching. In most cases, herd behaviour works to our advantage. It allows individuals to survive with less knowledge by depending on collective intelligence. We can’t know everything, so it is usually better to follow the herd. That saves time and energy. Social media is prone to herd behaviour. A cat video can become more popular because it’s already in favour, while a funnier one might go unnoticed.

The same is true for markets. During the Dot-com bubble, investors piled into Internet stocks. Many investors knew these stocks were crap, but they bought them anyway because they kept rising. And investing is about making money, not about selecting corporations with excellent prospects. Groupthink can cause stock market bubbles. In 1841, Charles Mackay wrote about three financial manias: Tulipomania in the Netherlands, John Law’s Mississippi Scheme, and the South Sea Bubble. He argued that greed and fear drive financial markets and that these emotions can make people act irrationally, to the point where they believe a tulip is worth a mansion.³

Confidence game

Information spreads via opinion makers and can lead to mass delusions. Confident but mistaken people play a crucial role in this process. Self-assured people aren’t always wrong, but when they are, they amplify their errors because they have followers. Most people are insecure and follow the lead of people who appear self-assured. Leaders must be self-assured. Otherwise, no one will follow them. Now, wise people do not appear self-assured because no one knows the future. The business of influencers on the Internet is making money out of insecure people by advertising products no one needs.

Confidence is contagious. During the Dot-com bubble, the loudest voices on Internet message boards boasted about their profits in Internet stocks, thereby pulling in more suckers. The quality of group decisions depends on how we aggregate information. To take advantage of collective intelligence, we could try to:

• make people feel free to come forward with their information and opinions;
• prevent groupthink or group members from becoming biased by the information or opinions of others;
• focus on the underlying causes rather than incidents.

That is difficult in small groups and even harder in societies. It is not how humans usually form opinions and cooperate. It goes against our nature. People derail discussions. Stupid people attract attention. And we don’t know the future, so what appears stupid today may prove to be great foresight tomorrow, and vice versa.

Collective action

Large groups struggle with addressing collective action problems. Humanity is the largest possible group of humans, so it faces the greatest possible challenges when it comes to issues that affect us all, most notably the looming technological-ecological apocalypse. It is not that most people are unwilling to contribute to the common good, but we already agree on what the common good is and the methods to achieve it. We can’t settle our arguments with reason because we don’t know the future. And then our unenlightened self-interest makes us seek personal gain at the expense of others. These are all ingredients of our collective stupidity that lead to our collective suicide.

As the collective wisdom of humanity is inferior to that of most individuals, the world might be better off with a single leader with unlimited authority. That can go wrong. During Mao’s Great Leap Forward, 30 million Chinese perished due to ill-advised policies. During that era, Mao ordered the mass murder of sparrows as part of the Four Pests campaign to eliminate rats, flies, mosquitoes, and sparrows. Sparrows eat grain but also eliminate insects, leading insects to feast on China’s crops. However, over 90% of the Chinese survived, so even a leader as stupid as Mao would outdo us. Someone slightly less stupid who accepts advice from experts might do even better.

Latest revision: 9 October 2026

1. Collective Stupidity – How Can We Avoid It? Sabine Hossenfelder. YouTube.
2. The Wisdom of Crowds. James Surowiecki (2004). Doubleday, Anchor.
3. Extraordinary Popular Delusions and the Madness of Crowds. Charles Mackay (1841). Richard Bentley, London.