Those words touched me deeply, because I had just spent several years imagining, researching, writing a book about, admiring, and above all empathizing with Antonina Zabinska, a Polish Catholic woman who risked her own life and her family’s to save more than 300 Jews during World War II. Her husband, Jan, the director of the Warsaw Zoo, had smuggled many of them out of the ghetto himself, and the refugees hid in the zoo’s bombed-out cages and were given the code names of the animals whose cages they occupied. Another dozen at a time hid in the nooks and crannies of their house, right on the zoo grounds, which German soldiers often patroled or visited. What first drew me to the story was Antonina’s phenomenal gift of empathy and her radiant compassion, both for humans and the other animals we call animals. With great hart ducha (Polish for a spirited heart), the Zabinskis also adopted orphan animals—hyena pups, a piglet, lynx kittens, a badger, a cockatoo, a rooster, a muskrat, and many more—and helped to preserve a primeval forest on the Polish-Belorussian border that is the refuge of many rare plants and animals. I’m usually smitten with the present moment, so conjuring up the historical past brought a host of challenges. It’s easy to sprain the emotions, and at times it hurt to sense my way into her blitzkrieged world. But I felt close to Antonina, a woman who, in order to savor the world from the sensuous perspective of a seal, elephant, or starling, would slip out of her self as if her self were nothing more than a sweater on a warm afternoon. She often relished imagining that she was a mother lynx, long and lithe, lying in a hollow full of soft, warm mulch, spending the day nursing and washing her kittens—only leaving them for a short time while they napped in order to sniff the ground for the musky scent of mink, fox, or boar, and to listen for the smallest rustle. In her mind, as she searched for animals hidden near the mossy trunks of old trees or in bushy shrubs, her eyes would be half-closed to see better in bright clearings but wide open in deep shade. Reading a faint movement in the distance, she would hunker down in tall grasses, nearly invisible but for nervous front paws and a slight twist of whiskers and, while keeping her eyes riveted on the prey, she’d feel tense and impatient from tip to tail, each muscle ready for her brain to shout “Pounce!” It’s an odd thing, I suppose, swapping one’s animal self for that of other creatures no less complex, carnal, or troubled. But shedding the self refreshes the mind. There’s also the lure of sensory novelty, with its bounty of new pleasures, frights, and games. And walking in another’s paws highlights our shared mortality and our unique morality. We can learn how to bridle our lust for territory and power; double-talk fear; turn what arose as monkey appeasement gestures into tactics of statecraft; and we can reword and rewire hatred. Most of nature doesn’t give or expect mercy. We’re the animals that strive to be seemly, merciful, and good. Still, our animal nature shames us. Though not all of us. Antonina believed that people could, should, and often do feature the best of their animal nature while rising above the worst. She undoubtedly owed her ability to bridge minds to richly developed mirror neurons, the hotbed of empathy. No doubt she inherited some of that ability and the rest, maybe the lion’s share, became ingrained during childhood when a brain is most maleable. But a gift for empathy is native to our species; our mirror neurons make us the social sleuths we are. We call it empathy when an animal thinks, “I know you think the way I would in your shoes, but do you know I know what you know?”An orangutan can easily do that. A litmus test for the different intelligence of humans involves added degrees of empathy, such as, “Does he know I know what he knows about what I know about him, and if so, would he respond the way I would in that situation, or would he respond the way I’ve seen some people respond when they thought I wasn’t watching, or, alternatively, when they knew I was watching, in which case, feeling self-conscious (as I would feel in that situation), they tried to out-think me?” Humans excel at this because we have livelier mirror neurons than other animals, but many animals do feel flights of empathy. According to her husband, Antonina viewed animals as cousins or alter egos, and they responded to her with an almost magical trust. He was a scientist who prided himself on being a cynical and hard-nosed realist, yet he believed her to be a mind-whisperer. In Antonina’s post-war recollections, she often wrote of the household pets as other sorts of people, some with eccentric dispositions, but all welcome. The pets fell under the heading of guests with a small g and, in accordance with her moral code, she offered those guests sublime hospitality and comfort. They were intimate strangers, not aliens, and when she gave them her full attention, mothered them, and wished them well, they relaxed in the safety of her care. This was also true of people, including Nazi visitors. After dark, the Jewish refugees, the household’s Guests with a capital G, would emerge from their hiding places to socialize, listen to the nightly piano concert, discuss the war, and laugh at the highjinx of the exotic pets. Her husband, who led a cell of saboteurs, fought in more traditional ways. But one of the most extraordinary things about Antonina was her determination to keep play, wonder, the arts, and even humor and innocence alive in a household of at times 50 refugees, where everyone feared the ever-present dangers, horrors, and uncertainties. That takes a special stripe of courage, one too rarely celebrated. We tend to think of heroes in terms of combat, but civilians also perform radical acts of compassion. We just don’t talk about those much, preferring instead to highlight the worst in human nature. I’m fascinated by how often and with what wholeheartedness so-called “ordinary”people risk subversive feats of compassion and sacrifice for complete strangers. The world would be a safer place if we reconsidered the ideal of the warrior hero. At the close of the captivating weekend in D.C., in which words like peace, compassion, and loving-kindness flowed freely among talk of neurons and theta waves, I visited the Holocaust Museum to view the artifacts and do some research in the library. In just a couple of hours, on that December day, my mental calipers widened to embrace two extremes of human behavior. On the one hand, some people will go to diabolical lengths when they get bored with the idylls of mayhem they’ve invented and, on the other hand, some will perform high-wire feats of compassion, altruism, and empathy. I looked back on the day and felt a profound sense of marvel about our species. For a moment, I paused at a mental overlook, one of those vistas that I cherish, when the human pageant seems to spread out below and my perspective deepens. The years of pleasure and hard work that had gone into writing the book evaporated, and I felt distilled into that one horizonless moment.