On the first page of If This Is a Man, later retitled Survival in Auschwitz, Primo Levi turns the Shema, Judaism’s most famous prayer, into an indelible curse. This is holy blasphemy, and unforgettable, as Levi intended it to be. Just before the gates of hell he grabs you with both hands, and doesn’t let go:Meditate that this came about:\nI commend these words to you.\nCarve them in your hearts\nAt home, in the street,\nGoing to bed, rising;\nRepeat them to your children,\nOr may your house fall apart,\nMay illness impede you,\nMay your children turn their faces from you.The practical-minded Levi, in a lovely image, once described his Jewishness as “like having a spare wheel, or an extra gear.” Here he uses what he knew about Jewish prayer, and so devastates us. The fact of the camp Auschwitz requires your constant meditation, or else you must endure a survivor’s curse.The words of Levi’s book, the most necessary of all books about the Shoah, are carved in your heart because they demand not just that you lament, but that you grasp what happened. (As if you could.) This is the Shema of Jewish desolation in the 20th century. And it echoes beyond the disaster visited on the Jews. I’ve been told, teaching this book, by students from Bosnia and Cambodia that it opened a door for them that would otherwise have stayed closed.“Hier ist kein warum” (there is no why here), one of the camp’s barbaric guards shouts at Häftling 174517, who used to be Primo Levi. But Levi disobeyed the order, driven by the need to find out why human beings acted as they did in Auschwitz, as both murderers and victims. Remembering Dante’s Ulysses, whose desire for knowledge made him human, Levi studied life in the camp with the tenacity of the scientist he was, relying on the durable tools of novelistic realism.Levi feels compelled to judge the people in Auschwitz, though he does so gently, as if compensating for the savage necessities of the lager. Having escaped from the inferno, he finds moral rules more, not less, pressing. He wants us to weigh each of the men and women he describes, so we can know what this place of mass death does to its inhabitants. This is no easy task, which is why Levi’s great book, unlike Elie Wiesel’s Night, works so well in the classroom. While Wiesel prompts reverence, never a promising mood for class discussion, Levi urges us to argue about his people. Wiesel clings to memories of emotional solidarity, whereas Levi is more interested in how prisoners use one another to survive.There is something else that divides these two most famous memoirists of the Shoah. Wiesel writes in a deeply moving, pitched monotone, while Levi has an antic sensibility that sometimes resembles Kafka’s. Yes, Levi is a comic writer, a bizarre fact given the inexhaustible darkness of his subject matter. We might expect from him the grim humor of his beloved Dante, but instead his jokes are often light. Levi speaks of “the spoons which, in those days, we kept with us day and night, ready for any and every improbable emergency, the way the Knights Templar bore their swords.” There is much darker comedy too in Levi, like the brutally absurd test for diarrhea undergone by prisoners in Ka-Be, the Auschwitz infirmary, a scene worthy of Kafka’s The Trial.Levi’s readers often think his title, If This Is a Man, refers to the Musulmänner, the barely human drowned ones shambling mutely through the senseless cruel tasks that make up life in the lager. Yet these faceless Musulmänner are not the main characters in Levi’s book. How could they be, since, so nearly dead, they no longer have any character at all?Levi focuses on the brilliant perverse operators, the swindlers, connivers, and power brokers among the prisoners. No reader can forget the superhuman dwarf Elias, with his vicious temper and herculean muscles, who carries stupendous loads, shouts, sings, curses, and laughs with “the violent mimicry of the deranged” (this last word is milder in the Italian—dissociato, dissociated), and steals constantly, downing 15 pints of soup at a time while others starve. Elias is a grotesque worthy of Rabelais, Levi’s favorite author, and his insane gusto makes him the most fitting of all human types for the lager, Levi decides. The vignette ends with a shock: “Elias, as far as we can judge from outside, and as far as the phrase can have meaning, was probably a happy person.”In a later book, Moments of Reprieve, Levi shows us another bizarrely cheerful prisoner, Rappoport. Like Elias, he is a well-fed, insolent operator. “Shrewd, violent, and happy as the adventurers of earlier days,” Rappoport, when he hears an air raid siren, steals a pail of soup in the midst of the chaos. He chatters constantly of the good times before Auschwitz. “While I could I drank, I ate, I made love, I left flat gray Poland for that Italy of yours.” He remembers the Italian women, the black-market steaks, the wine. “Things went well for me … and all that good has not disappeared. It’s inside me, safe and sound,” he brags.“If I meet Hitler in the other world,” says Rappoport, “I’ll spit in his face and I’ll have every right to …”—here a bomb falls on a warehouse, so Rappoport has to talk louder—“because he didn’t get the better of me.” Rappoport’s defiance is in part mere delusion, yet Levi admires it. “In the sad event that one of you should survive me,” Rappoport announces, “you will be able to say that Leon Rappoport got what was due him, left behind neither debits nor credits, and did not weep or ask for pity.” Reacting to this boast, which is worthy of Dante’s Farinata, Levi is mordant but also respectful: “I have reason to believe that Rappoport did not survive. So I considered it my duty to perform as best I could the task with which I was entrusted.”***Levi judged not only the Holocaust’s victims and perpetrators but the ones who stood by with averted eyes while it happened. Judging, he knew, if it was going to be worth anything, had to come from understanding. And there was something in the Germans that Levi could never understand, though it was crucial that he keep trying.The most pressing instance for Levi was Ferdinand Meyer, the chemist who appears under the name Müller in The Periodic Table. When Levi arrived in the chemistry lab at Buna-Monowitz (Auschwitz III), Meyer helped him. He gave him a pair of leather shoes and, just as important, spoke to him using the formal sie, rather than the familiar, insulting du that Germans used when talking to Jews in the camps. But Meyer was still one of the German masters, on the other side of an insurmountable wall.Throughout his life after Auschwitz Meyer was burdened by guilt. In 1967 he began writing to Levi, who had tracked him down through a mutual friend, and told him, “I was filled with joy that you escaped the hell of Auschwitz.” (These details are taken from Ian Thomson’s superbly researched biography of Levi.)Levi still had mixed feelings about Meyer, who seems to have been willfully oblivious to the real purpose of Auschwitz. When Levi asked Meyer what he knew about Birkenau’s death factory, he replied, “During my short stay at Auschwitz I was not aware of any incident aimed at exterminating the Jews.” In The Periodic Table Levi comments on this acidly: “He too, obviously, had not demanded explanations from anyone, not even from himself, although on clear days the flames of the crematorium were visible from the Buna laboratory.”But Levi goes on, softening a little. “I did not love him, and I didn’t want to see him,” he writes about Meyer, “and yet I felt a certain measure of respect for him. … He was not cowardly, or deaf, or a cynic, he had not conformed, he was trying to settle his accounts with the past and they didn’t tally: he tried to make them tally, perhaps by cheating a little bit.” Meyer’s “condemnation of Nazism was timid and evasive, but he did not seek justifications.”Levi in the end decided that Meyer was “neither infamous nor a hero,” and that the way he relied on clichés about human evil, barbarism and hope in his letters to Levi “was better than the florid obtuseness of the other Germans: his efforts to overcome [the past] were clumsy, a bit ridiculous, irritating and sad, and yet decorous. And didn’t he get me a pair of shoes?” Levi got an anguished phone call from Meyer and in the end agreed to see him, but Meyer died from a sudden heart attack before their meeting could happen. What remains is Levi’s finely turned reflection on Meyer’s evasions, which is also about his own struggle to respond to the German chemist.Only a few survived the camps without renouncing part of their moral world, Levi wrote, and he was not among those few. Levi knew his own moral failures, though he knew too that there was no comparison between the victims’ guilt and the murderers’. He was never cruel, but he did learn indifference to the panorama of suffering, as the terrible law of the lager required. The Musulmänner ready for death seemed merely repellent; the needy prisoners, with their hard luck stories, were useless and therefore to be avoided.The camp’s worst cruelty was that one’s survival seemed stolen from another. Levi thought he had survived the selection of October 1944 only because the SS officer who decided with a glance who would live and who would go to the gas had confused him with a healthier prisoner named René, who stood next to him in the line.This moment, deftly touched on in If This Is a Man, stands in for a more crucial loss. Levi’s beloved, Vanda Maestro, had been deported to Auschwitz with him. In the fall of 1944 an Italian friend saw Vanda, “white as chalk,” and heard her say “those awful words, which I can never forget,” “Io non ritornerò,” “I’m not coming home.” In January 1945 Levi found out that Vanda, by then a human skeleton, had been sent to the gas chamber months before. “I knew with extreme clarity that I would suffer later for her death,” he said. “Levi felt he should have died in Vanda’s place,” Thomson writes.In October of 1945 Levi reached Turin after his long wanderings through Soviet territory, and on his first night home he slept with a piece of bread under his pillow. He rehearsed his memories of Auschwitz, telling his tales to anyone who would listen. Once on a train a fellow passenger, overhearing Levi, asked him to speak louder, so compelling was his story.Just as he did on that train, Levi in his books persuades you to listen, and not only to the history of the murdered Jews but to the equally unimaginable histories that scar more recent times. Now, 100 years after his birth, Primo Levi still demands that you listen.