The most discomposing thing about people capable of monstrous acts is that they too enjoy art, they too read to their children, they too can be moved to tears by music. The dissident poet Joseph Brodsky captured this as he contemplated the greatest antidote to evil, observing that “no matter how evil your enemy is, the crucial thing is that he is human.” Little Prince author Antoine de Saint-Exupéry experienced it first-hand when a smile and a cigarette exchanged with an enemy saved his life while captive as a prisoner of war.

In the spring of 1935, traveling through Nazi-infested Europe, Virginia Woolf and her Jewish husband Leonard came face to face with this haunting paradox of human nature — an experience both sinister and strangely hopeful.

After a week of savoring Rembrandts and Vermeers and fine weather in Holland, the Woolfs reached the German border. Ahead of them, trucks with swastikas were passing through. They stopped. Leonard disappeared into the customs house. Virginia stayed in the car, trying to read D.H. Lawrence while shuddering at the passing minutes — it was taking much longer than at the Dutch border. She busied herself writing in her diary:

Sitting in the sun outside the German Customs. A car with the swastika on the back window has just passed through the barrier into Germany. L. is in the Customs. I am nibbling at Aaron’s Rod. Ought I to go in and see what is happening? A fine dry windy morning. The Dutch Customs took 10 seconds. This has taken 10 minutes already. The windows are barred.

Just then, as Virginia watched a little boy open his bag at the barrier with a Heil Hitler salute, the German officer — a “grim man” — came out and issued a jolly laugh upon seeing Mitz — the sickly pet marmoset the Woolfs had taken along on a whim, now perched on Leonard’s shoulder.

The Nazi, still laughing, let them through.

Virginia grew giddy with relief, then immediately horrified by the grisly incongruity of evil and delight:

We become obsequious — delighted that is when the officer smiles at Mitzi — the first stoop in our back.

The Woolfs continued through Germany. In Cologne, they were awed by the majestic Gothic cathedral. In Bonn, they made a pilgrimage to Beethoven’s childhood home. But when they tried to cross the Rhine, they found themselves trapped in a Nazi procession along a street lined with armed Nazi officers and adorned with banners that read THE JEW IS OUR ENEMY. All around them uniformed schoolchildren — hundreds of them — were singing and waving red swastika flags.

As the car crawled through the frenzied mob with the top rolled down, Mitz once again became their ticket to safety.

In her improbable and charming book Mitz: The Marmoset of Bloomsbury (public library), Sigrid Nunez paints a vivid vignette:

Came a man in black uniform, face very red. He threw up his hands, he shook his fists, he lifted one knee and then the other and stamped his feet. He was a swastika himself, all angles, twisted, black and red. He bore down on the car. Leonard felt for the letter in his pocket. Mitz, excited by the noise and the flags and now this amusing fellow, leapt onto the steering wheel and screeched. The man stopped in his tracks. Surprise, then puzzlement, then tenderness showed in his face. “Ah — oh — ah!” he cried. He clapped his hands like a child. “Das liebe kleine Ding!”

It was as if the Woolfs had vanished. The storm trooper had eyes only for Mitz. He leaned into the car, and Leonard inhaled a mixture of beer, onion, leather, pomade, and sweat. The man wagged a finger at Mitz, and Virginia closed her eyes and sent up a prayer that Mitz would not bite it. Bite it she did, though — but this seemed only to increase his delight. He burbled and cooed, offering wurst fingers to Mitz, one by one. And what was the sweet little creature’s name? When he heard it he laughed and repeated it several times, slapping his thigh. He loved it — loved it! At last he stepped back from the car, clicked his heels together, and raised his arm. “Heil Hitler!”

They were let through. As they continued on, the scene was repeated again and again along the German roads. Leonard himself recounted in his autobiography:

When they saw Mitz, the crowd shrieked with delight. Mile after mile I drove between the two lines of corybantic Germans, and the whole way they shouted “Heil Hitler! Heil Hitler!” to Mitz and gave her (and secondarily Virginia and me) the Hitler salute with outstretched arm.

Shining a sidewise gleam on the paradoxes of human nature, he added wryly:

It was obvious to the most anti-Semitic stormtrooper that no one who had on his shoulder such a ‘dear little thing’ could be a Jew.

Soon, Virginia was writing to a friend:

Did we tell you how the marmoset saved us from Hitler?

Emerging from it all is a chilling testament to how arbitrary the things are that humanize or dehumanize a person, and how banal — exquisite evidence for what Hannah Arendt so memorably termed “the banality of evil.”

Emerging also is the recognition that, for all of our foibles, all of our vulnerability to ideological manipulation, all of our capacity for cruelty, it is tenderness we most long for, tenderness that is our deepest nature.

The challenge is how to live with the knowledge that what steers us one way or another, toward terror or tenderness, can be the faintest and most random ripple in the surface of consciousness — just a “wave in the mind,” to borrow Virginia’s own lovely phrase.