We know good people when we encounter them, when they fall upon our lives like a sunbeam, like a song. But we don’t always know what makes them good. It has, of course, a lot to do with kindness. It has to do with their capacity to give, and also to receive. It has to do with their courage of uncertainty. And yet like all the great truths, the essence of a person, the goodness of a person, is both clear and ineffable.

In the bleak Siberian winter of 1856, Fyodor Dostoyevsky (November 11, 1821–February 9, 1881) — thirty-five, dreaming of being a writer while stationed at a labor camp, having narrowly escaped a death sentence that had given him a lucid glimpse of the meaning of life — sent his older brother a letter of introduction to a young friend whose goodness had touched his life, had changed it. “In the most selfless way he has undertaken to look after my concerns and help me with all his might,” Dostoyevsky tells his brother, “and he loves me.”

Throughout the ten-page letter, he goes on to enumerate his friend’s noble qualities. Pulsating beneath the particular is a simple, precise articulation of what makes a good person in a universal sense. (In one of the most logically elegant and morally compelling arguments for humanity, Dostoyevsky believed there are no bad people — which is precisely what renders his concern with goodness all the more commanding.)

“He is a very young, very gentle person,” he writes, “but with a strongly developed point of honor, incredibly kind.” In describing his friend’s modest education and intellectual disposition, he makes a subtle, profound point — it is far better to enjoy studying than to be overeducated.

“I live in great poverty,” Dostoyevsky tells his brother, “deny myself everything, and in the meantime I’ve made debts!” Perennially penurious, he was constantly asking friends, relatives, acquaintances, and even near-strangers for loans, which he rarely repaid. His young friend frequently helped him financially and not once asked for the money back, implicitly understanding that money is not a special species of resource, but — like time, like love — just another form of energy that circulates between us, flowing toward where it is most needed. “He blushes when I start up about my debt,” Dostoyevsky writes, “and is even annoyed if I remind him of it” — a beautiful testament to the non-transactional nature of true generosity.

In a passage that calls to mind D.H. Lawrence’s timeless insight into the strength of the sensitive, Dostoyevsky arrives at the young man’s noblest quality. Observing that he is “prone to depression and rather over-anxious,” he reflects on the superpower of his friend’s vulnerability — one all the more needed in our Age of Outrage:

What infuriates and enrages someone else saddens him — the sign of a superior heart.

Couple with Susan Sontag on what it means to be a good human being, then revisit the day Dostoyevsky discovered the meaning of life in a dream.