Robert J. Aumann isn’t only famous for his long white beard and deep sense of wisdom. He’s also renowned for a string of controversies. On one hand, his strong political views on the Middle East conflict strike deep divisions in opinion. On the other, his work on game theory is hailed by the Nobel committee - recognized to have profoundly helped our understanding of conflict, and how to make the world a better, more peaceful place. Aumann seeks solutions to conflicts that seem to be intractable in hard numbers and equations. The only problem is: people may not like them.
His award-winning work and political beliefs are both driven by his own turbulent life story. Aumann is a German Jew who endured the Second World War, lived through the Cold War, and now calls the Middle East conflict zone his home.
Robert J. Aumann
The Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel, 2005
At a glance
Born: 1930, Germany, Frankfurt am Main
Field: Game theory; mathematics
Prize-winning work: Profound game theory analysis on conflict and cooperation, especially through studies on repeated games
Fitness: Reached the peak of Via Ferrata in the Dolomites (10826,77 ft.) in his 80s
Unexplored areas: Hasn’t seen himself without a beard for decades
What does game theory teach us about human behavior?
Game theorists study strategies between rational decision makers - situations of conflict and cooperation. And when first meeting Aumann, said to be the mathematical genius of game theory, he starts by discussing war, destruction and disarmament in his very own emotional way. So it’s not unusual that when being asked about the everlasting conflict of mankind - war - his thoughts soon drift to butterflies.
"There are many things like that in nature," Aumann says, introducing an example. When the first male butterfly lands somewhere, he owns it. "But sometimes two males might arrive at once," which in human understanding, can only be resolved through combat. "But nature has evolved a strategy: if two males come at the same time, then both of them leave. So nobody gets hurt," he says.
It only sounds simple thanks to the professor. But the so-called correlated equilibrium - a theory where both parties can’t follow a dominant strategy and have only one chance of ‘winning’: an outside influence - is only one of his main contributions. And just a small part of the Nobel committee’s decision to award him its highest honor.
What can we learn from the Cold War?
"War is the one constant of mankind," he explains. It’s also a very significant constant in the life of an observant Jew. Sitting in his living room with his second wife Batya, he’s able to ponder his home-baked cheesecake with the same intensity as he philosophizes about his studies. But the old German recipe soon makes Aumann remembers his early childhood. Their upbringing in Nazi-Germany and the memories, as Aumann says, are still vivid in his mind. "In the store windows in Frankfurt, there was a sign with a light brown background and black lettering. It was in German, but was made to imitate Hebrew lettering. And it said: "Juden sind hier unerwünscht". Which means: Jews are unwanted in this store." There’s a moment of intimate silence while Aumann seems to travel through time, imitating the sound of the train that brought him away from his hometown Frankfurt. He becomes the eight-year-old boy he was in those days, his voice shaky, his eyes wet.
More or less ready to start over in the United States, "Johnny", as Aumann is known to his closest friends, saw the pressure of the Cold War. The nuclear threat not only had a significant impact on him personally, but also the development of game theory.
When the likelihood of nuclear war nears tipping point, it leads to Mutual Assured Destruction - where neither side has any incentive to either attack or disarm. The fear of being attacked by weapons of mass destruction prevents both sides from using them themselves. A kind of nuclear stalemate.
Why should we take revenge?
"There are all kinds of human traits that come out of repeated games," Aumann explains, referring to an ongoing conflict. "For example, revenge. Revenge doesn’t seem to make any sense. Why take revenge? You have already suffered some kind of loss, why does it help you to take revenge on the person that inflicted this loss?"
But Aumann argues that without revenge, there’s no deterrent. "So the revenge has to be part of the culture to enforce the cooperative behavior that takes place when people help each other, because they fear revenge. But that means that when they do harm each other, then the revenge has to be put into operation."
The crux of his theory leads to heated criticism when Aumann declares: "We need to be prepared for war; we must be willing to fight in order not to fight!"
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How do we avoid wars?
With a raised finger, Aumann points to a scribble on his office white board. It’s a quote from Barack Obama’s Nobel Prize speech, and reads: "The belief that peace is desirable is rarely enough to achieve it." He bangs on the table and shouts:
We all like peace. But how do we get it?
Solving this question is probably the highest aim of the profession, and to do so, Aumann believes you need to dismiss the idea that war is irrational.
"If you dismiss things as being irrational, then you can’t deal with them. You haven’t helped the world. You have to give proper incentives to the sides not to go to war. If you capitulate, then you’re more likely to promote war than to avoid it. Overtly cooperative behavior which is not matched is negative, it doesn’t work."
Why war isn’t senseless
Aumann’s definition of rationality is different to others’. "Rationality is pursuing your own goals; this is the economics definition. It’s to pursue your goals to the best of your ability on the basis of the information that you have. It’s not being scientific, it’s not being logical, it’s none of that."
The professor admits it’s difficult for laymen to get their head around this idea. But then he shares an example from a former student: "If a black cat crosses your path, and you spit, are you rational or irrational? Well, in the everyday language, you are highly irrational. It’s a stupid superstition that a black cat means bad luck, it’s an even more stupid superstition that spitting avoids bad luck. It’s highly irrational. But by the economics definition you have to spit. Because if you’re superstitious, your information is that spitting avoids bad luck."
Rationality is pursuing your own goals… It’s to pursue your goals to the best of your ability on the basis of the information that you have.
It’s true, Aumann has been condemned for his personal political opinions about his home country. But many scientists point back to his fundamental contributions to science that have done more than anyone else of his generation to define the most rewarding questions of game theory.
For Aumann, the most challenging part, is questioning whether a theory alone can really avoid wars. His answer comes, as usual, with a rich dose of wisdom. He strokes his beard, and then says loudly and emphatically: "No theory is able to avoid wars. People have to avoid wars!"
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