This is Hidden Brain. I'm Shankar Vedantam.

In February 1945, as World War II was nearing its end in Europe,

the leaders of the three major allied powers,

the United States, Britain and the Soviet Union,

met at the Yalta Conference in Crimea to discuss the terms of Germany's surrender.

The Soviet Premier, Joseph Stalin, wanted Germany to discuss the terms of Germany's surrender.

The Soviet Premier, Joseph Stalin, wanted Germany to pay $20 billion in reparations, the equivalent of $333 billion in today's money.

Such a demand would almost certainly have caused economic collapse in Germany.

This seemed to be Joseph Stalin's goal,

destroyed Germany to ensure it could never rise again as a threat.

In his eyes, Nazi Germany had more than earned such punishment.

The Western allies were against this approach.

They were not interested in punishing Germany.

The war was almost over.

They saw how the punitive terms imposed on Germany after World War I had backfired,

leading to the rise of Adolf Hitler and the Nazis.

The United States and Britain wanted to focus on Europe's long-term stability rather than look backwards at the death and destruction that Germany had caused.

Today on the show, we examine these conflicting impulses.

We've all heard the phrase, an eye for an eye, a tooth for a tooth.

The idea is simple. When someone commits a terrible act, they should pay an equally terrible price.

It feels fair. It feels just. But does it always make sense? For them? For us?

This week on Hidden Brain, we examine the psychology of revenge. What causes people to prioritize the destruction of others, even if it risks

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