The theme for this year’s Holocaust Memorial Day is a vast one, going to the core of what is important about what happened in the Holocaust, and offering a sharp analytical tool to cut through what can sometimes be inaccurate, inappropriate, or simply inauthentic in Holocaust memorialisation. It also, if we choose, could be a rallying cry of hope for the world, but for the moment let me stick to what I know.

Like any historical event, the Holocaust has to be understood from the specifics up, and “lessons” must be drawn advisedly. If, in the solemn words of a 1968 anthology of Holocaust literature, we claim that “A whirlwind cannot be taught; it must be experienced” we cut ourselves off from what is important. Because if it cannot be taught, nor can it be learned from. For the learning to be done from a storm is limited, and we know there will be others: at some point, all we can do is take shelter and pray to be spared. But the Holocaust was not a natural disaster. It was the product of human actions on the basis of human decisions. We do violence to history if we paint its victims automatically as saints or its perpetrators as monsters.

Adam Czerniaków was an engineer and a Senator in the interwar Polish parliament. After occupation of the city, he was appointed Chairman of the Jewish council, responsible for the second-largest community of Jews in the world. The 300,000 Jews of Warsaw were outnumbered only by the Jews of New York, and during the twenty months Czerniaków was Chairman, Warsaw Jewry swelled to 450,000. In his endless attempts to square the demands of the Germans with the meagre resources the community had to help itself he won few friends, though his diaries show little of either the ego or subservience his critics accused him of. In July 1942, confronted with the request to organise the deportation of children from the ghetto, he committed suicide. Was this a final act of cowardice (as the great Polish-Jewish historian Emanuel Ringelblum claimed) or just the exhausted response of a man who had on more than one occasion gone from being beaten to a meeting to discuss how the ghetto managed its affairs? And who had endured both the hatred of those he tried to protect and the contempt of those he tried to placate. While the order sealing the ghetto came from the German governor of Warsaw, the final orders for the destruction of the ghetto were delivered by a junior officer. The final notice required no more explanation or debate; nothing more than a delivery man.

In Łódź, the Chairman of the Council – the self-styled “Elder of the Jews” – was Mordechai Chaim Rumkowski. A not very successful and not very well known businessman, he was appointed at around the same time as Czerniakow. When confronted in 1942 with the order to deport the children and the elderly, he complied, haranguing the ghetto that he would cut off the limbs to save the body, and making clear that only those who worked would survive. His ego, love of the limelight, and disturbing claims about his behaviour with the ghetto’s children, all fit him for the villain’s costume. And yet, as Yehuda Bauer has pointed out, the Łódź ghetto was finally liquidated in August 1944: had the Russian army advanced just a little quicker, we might now be talking of him as a pragmatic survivor.

The survivors knew – and, in their ever-smaller numbers, know – how frail and difficult such judgments are. Primo Levi, in his most heartfelt (and final) book, The Drowned and the Saved, acknowledged that “We, the survivors, are an anomalous minority. Those who saw the Gorgon, have not returned to tell about it or have returned mute, but they are […] the submerged, the complete witnesses, the ones whose depositions would have general significance. They are the rule, we are the exception.”

There comes a moment in every testimony, however professionally delivered, where the survivor once again encounters the slimness of the margin that brought them through their experiences safely but not others. Considerable scholarly energy has been directed at this. Initially survivors were thought to be racked by guilt. But guilt implies a charge which can be reversed or appealed in light of evidence. If we believe ourselves to be guilty, we usually have a basis for this, rightly or wrongly. We are ashamed, however, if we feel ourselves helpless in the face of wrongdoing. As Levi wrote of his liberators, arriving out of the mist 78 years ago today:

“They did not greet us, nor smile; they seemed oppressed, not only by pity but also by a confused restraint which sealed their mouths, and kept their eyes fastened on the funereal scene. It was the same shame which we knew so well, which submerged us after the selections, and every time we had to undergo or witness an outrage: the shame the Germans never knew, the shame which the just man experiences when confronted by a crime committed by another, and he feels remorse by its existence, because of its having been introduced into the world of existing things, and because his will has proven nonexistent or feeble and was incapable of putting up a good defence.”

Tadeusz Borowski, a Polish survivor of Auschwitz whose narrative persona in his Auschwitz stories was at odds with the generous and kind man his contemporaries remembered, observed that the key to the Nazi system was in reducing everyone and everything to its level.

“The first duty of Auschwitzers is to make clear just what a camp is…but let them not forget that the reader will unfalteringly ask: But how did it happen that you survived? […] Tell, then, how you bought places in the hospital, easy posts, how you shoved [them] into the oven, how you bought women, men, what you did in the barracks, unloading the transports, at the gypsy camp; tell about the daily life of the camp, about the hierarchy of fear, about the loneliness of every man. But write that you, you were the ones that did this. That a portion of the sad fame of Auschwitz belongs to you as well.“

You could not survive without being implicated in the death of another. Another survivor, Jean Amery, argued that “a man, once tortured, remains tortured” – perhaps chiefly by Amery’s own awareness that the only way to fully communicate pain is to inflict it. Levi’s first book was called “If this is a man”: I suspect the key to understanding all of these men, and other survivors besides, is to see that title as a question: directed firstly and most uncompromisingly at themselves. In undermining their core belief in their personhood – that they were and remained ordinary people – we see the evil of the totalitarian mindset which divides us all: into important or not, deserving or not, ordinary or not, and ultimately alive or not.

It is those categories which drove the killers. Demanding first that the individual be quantified, held to some fantastic genetic account was the first step. In the first years of the Nazi regime, the individual became required – by custom rather than laws in most cases – to give an account of their family history. A thriving industry sprang up, with genealogical researchers advertising their services, and different companies offering easy-to-carry versions of the Ahnenpass (ancestors’ record) detailing ancestry as far back as a given institution or organisation wished. It was partly to help resolve the myriad complications thrown up by this process that the Nuremberg Laws were introduced in 1935. First came the elimination of doubt and then came the elimination of the people who embodied those doubts.

It is comforting at this point to imagine that the killers believed their victims to be something other than ordinary people. There were certainly efforts to portray Jews as vermin, and the degraded communities of the ghettos seemed to confirm the propaganda. For some, by the time they encountered actual Jews, they saw only the phantasm of “The Jew”. Alfred Rosenberg, the ideologue of the Third Reich, commented after visiting Warsaw: “If there are any people left who still somehow have sympathy with the Jews then they ought to be recommended to have a look at such a ghetto. Seeing this race en masse, which is decaying, decomposing, and rotten to the core will banish any sentimental humanitarianism.” A Polish government report in May 1942 described how “Every day large coaches come to the ghetto; they take soldiers through as if it was a zoo. It is the thing to do to provoke the wild animals.”

For others, however, there is a more disturbing picture. The men of Reserve Police Battalion 101 were not impressionable youths whose views had been moulded by Nazi propaganda since childhood. They were middle-aged, and stolid. Nor, from Protestant North Germany, were they entirely typical Nazi voters in 1933. And yet, when offered the chance in July 1942 to be excused the actual killing if they wished, just one man stepped out of line. The battalion went on to be prolific and proficient – but only in a relatively few cases enthusiastic – killers. They were neither the supernatural horror of a B-movie special effects department nor the rigid-armed automata of early textbooks. They were, far more terrifyingly, ordinary people too. And they killed just like the others, whose extremity makes them more accommodating fixtures in the mental landscape. Once, while teaching a session, I asked the very wise man Steven Frank, whose childhood in Terezin I have heard him describe many times, how many monsters he met. He hesitated and I could see his genial nature strip back for a moment, before conceding, “Not many, actually.”

Of course there were monsters. Josef Mengele and Carl Clauberg, in their blank disregard for those on whom they performed medical “experiments” in Auschwitz. Heinrich Himmler, with his prim insistence that carrying out the extermination had made the SS hard but at no moral cost as long as they did not enrich themselves. The men around the table at Wannsee, calmly discussing the progress, scope, and implementation of mass murder before proceeding to lunch. There were sadists, sociopaths, and others. But even here we cannot know for sure that they were born wanting to do these things.

These challenges are the tests of the efforts this week to memorialise the Holocaust. Do they ask you to find complex and challenging answers to uncomfortable questions? Or do they you offer you reassurance that no, it could not happen here, not now, not by us.

Because it could. The full complexity of the debate on trans rights is not my field of expertise, nor is the plight of refugees. As ever, find a voice of experience, and listen, taking as your starting-point the idea that the person you encounter is ordinary, like you. But when a small minority becomes enlarged into an omnipresent and omnipotent threat out of all proportion to its size? That is my field. What happens when the self-identification of individuals becomes the business of everyone with half an opinion, that is my field. And what happens when the demand to police an illusory certainty acquires lethal momentum, that is very much my field. The elimination of doubt about what people are will always end in the elimination of people themselves if it is not checked by rigour, by empathy, and by compassion. Otherwise, the only way to eliminate the doubt is to eliminate the people. And that happens symbolically first, as we move them from those we deem “ordinary” and entitled to consideration and rights, and into another category, where maybe the rules of humanity do not fully apply. Every other step is a commentary on that first one.

Primo Levi died shortly after completing The Drowned and the Saved. He fell down a lift shaft in his Turin apartment building. Some have argued that it was not suicide since there was no note. But a cursory reading of his work reveals a man only desperately kept from the final discharge of his life by the writing of its explanation. In his essay ‘The Gray Zone’ in which he discussed Rumkowski among others, he concluded that “we are all in the ghetto, that the ghetto is walled in, that outside the ghetto reign the lords of death, and that close by the train is waiting.”

On one level, it is a tragic measure of how far this good, wise, brave man felt trapped by his experience. On another, it is a warning: of how far we may fall when we are not prepared to face the consequences of knowing the Holocaust was perpetrated by and on ordinary people. Before you call for the walls to be higher, for the lords of death to be more particular in their judgment, ask for whom the train is waiting. It could be you, it could be me: we are, after all, ordinary people.