“The only true thoughts are those that don’t understand themselves”, Adorno writes in Minima Moralia. The sentence stands on its own—a “monogram”, Adorno calls it—without any context that would help illuminate its paradoxical meaning. That Adorno believed truth to be something not easily possessed is hardly surprising, The elusiveness of truth, the fact that truth is a process rather than an end, that truth has a “temporal core”—these are all central tenets of Adorno’s thinking. But to get to the heart of this aphorism, we have to go a step further and ask why, according to Adorno, truth is out of our reach—or more precisely, incomprehensible. Why do true thoughts not understand themselves? And conversely, why are thoughts that understand themselves not true? For Adorno, the answer has to do with the nature of reason and the fundamental structure of our understanding, and it is closely linked to that elusive other that lies at the very heart of his philosophy: the nonidentical. The relationship of reason to the world is fundamentally conceptual—connected to expression and thus to concepts: to grasp something, we name it. The problem is that we have a limited number of names at our disposal, for an unlimited number of phenomena. Reason solves this conundrum by subsuming the infinite richness of our world under a finite number of concepts, in other words, by pretending that what is different is in fact the same. It identifies the unique phenomenon as a specimen of a category and forces it into the Procrustean bed of conceptuality, treating the unknown as long known, the singular as an instance. This “identity thinking”, as Adorno calls it, allows us to form thoughts and makes intersubjective communication possible, but it comes at a price: the elimination of the nonidentical, that which is unique and therefore inexpressible. Adorno called the nonidentical the “concept’s other” (DSH 5:363/133), the “ungrasped”, the “incomprehensible” (DSH 5:375/147). The nonidentical is that part of the truth that we, quite literally, cannot comprehend, that which slips between the cracks of our conceptual rationality, the unsayable and unsaid that prevents us from having a complete grasp of the world around us and makes all the thoughts that we can comprehend incomplete and therefore untrue.

Adorno’s philosophy grows out of the tension at the heart of rational thought: between the subject’s need to conceptualize, categorize and subsume, and the object’s own objectivity, the nonidentical that is erased in a thought cut to fit. “The utopia of knowledge would be to open up the non-conceptual with concepts without making it like them” (ND 6:21/10), Adorno wrote in Negative Dialectic—a utopia he pursued all his life. He did it by opening up conceptual rationality to the nonconceptual: to the aesthetic, the somatic, the ephemeral; by letting our ratio take cues from that which is not like it. The driving force behind his effort was nothing less than the desperate desire to save the nonidentical from obliteration by reason. But why save the nonidentical? Was Adorno animated by the same age-old quest for Truth with a capital T, the search for the elusive essence, the thing in itself, that had fueled philosophy since its earliest beginnings? The answer is yes and no. If Adorno wanted to get closer to truth, it was for a reason so down-to-earth that many of his philosophical predecessors (and contemporaries) would have recoiled from it in contempt. Adorno wanted to save the nonidentical not because it stood between him and a full disclosure of Truth, but because he was convinced that silencing it plays a prominent role in very real suffering.

Indeed, despite its elusiveness, the implications of the nonidentical—or more precisely: of its constant erasure—are utterly concrete. Adorno’s work reveals how social structures of domination, the withering of individual experience, social ills such as bigotry, racism, authoritarianism, political polarization, and ultimately even genocide, are more or less directly linked to identity thinking and the fate of the nonidentical, and with it to the most fundamental underpinnings of constitutive subjectivity. Because we depend on concepts to grasp the infinite richness of the phenomenal world and of our own experience of it, because we need to identify in order to make sense, our thinking is, inescapably, identity thinking: it levels and makes the same, mutilating the object and the subject trying to grasp it. The conceptual framework of our mind, thus Adorno’s sweeping claim, is inherently incapable of doing justice to singularity, and the collateral victim of that inability is the nonidentical, before us and within us.

At its epistemological root, the idea of the nonidentical may seem banal, a simple asterisk added to the concept. “Hold on” is what it seems to tell us: you are missing something. Your concept doesn’t tell you the whole truth. You see an old Arab woman? Think of all the things that your mind just erased by seeing her as what she falls under, all the pains and riches that fall between the cracks of the predicates old, Arab and woman. One could be tempted to say, so what? I know that this woman is unique. Just because I categorize her in thought, connect my experience with the words that allow me to express it, doesn’t mean that I don’t see her unicity. Yet Adorno’s point is precisely that the subsumptions of our mind, the urge of rational thought to make everything the same, are not as harmless as we would like to think—as inevitable as they may be. There is a close connection between identity in reason and the identity we impose on the world and on ourselves, and the implications are far-reaching. Adorno’s work is a monumental reflection on these implications—on all the different ways in which we erase the nonidentical, and on how to resist the irresistible pull of identity. What starts as an epistemological analysis becomes a reflection on experience, society, history, ethics, art, writing, logos and somos, nature and man. The notion of the nonidentical equally grows, leading from its epistemological core to the social outcast, the artwork, the “torturable body”, the transcendent, the somatic in reasoning, history in truth.

Adorno’s conviction that history affects and transforms truth is intimately linked to the reality of human suffering. “The need to give voice to suffering is the condition of all truth”, he wrote in Negative Dialectic, and declared that every thought should have “as its inspiring force, the desire that things be right, that men reach a state in which the pointless suffering ends” (VND 82–3/53). For him, one event stood out in the endless history of suffering: the one he metonymically calls Auschwitz. Standing for a suffering unprecedented in its scale, Auschwitz became for Adorno the rod against which truth henceforth had to be measured. Its importance in his work can hardly be overstated, and it is closely connected to the centrality of the nonidentical in the latter. “Auschwitz”, Adorno wrote in Negative Dialectic, “confirms the philosopheme of pure identity as death” (ND 6:355/362). While identity thinking does not inexorably end in genocide, the awareness that it potentially can is crucial to ensure that it never will again—a goal that, according to Adorno, all human thought and action had henceforth to be directed towards: “Hitler has imposed upon humanity in their unfreedom a new categorical imperative: to arrange their thinking and conduct so that Auschwitz will never repeat itself, that nothing similar will ever happen” (ND 6:358/365). That imperative informs and shapes Adorno’s philosophy and its focus on the nonidentical. Explicitly or between the lines, Auschwitz as the epitome of pain suffered and inflicted, and the nonidentical as the locus of suffering in thought, are the two poles of Adorno’s thought, as much Mittelpunkte, implicit reference points, as objects of inquiry.

The present study is composed of three parts, each centered on one of Adorno’s three magna opera and focused on the genesis and the numerous forms and traces of the nonidentical in the latter. I begin my investigation with Dialectic of Enlightenment, Adorno’s first major book, co-written with his lifelong friend and philosophical companion Max Horkheimer during the wartime exile. Dialectic of Enlightenment presents us with the diagnosis from which all of Adorno’s later work will stem: “The wholly enlightened Earth is radiant with triumphant calamity [Unheil]” (DA 3:19/1). Reason’s progress is unstoppable, the dogmas and fears of yore have been emasculated, man is more and more master over nature—and yet, not only has the promised land of the free and satiated not materialized, but new authoritarian regimes have sprung up and thrive in the very heart of enlightened Europe. Adorno’s and Horkeimer’s analysis of what went wrong is an account of how enlightened reason, in its effort to overcome myth, disqualified everything that did not meet its newly enthroned criteria of verifiability, univocity, non-contradiction and, last but not least, identity. In its urge to dominate nature, it categorized and subsumed all things without and within, discarding whatever did not fit. Thus began the long road of suffering of the nonidentical. Dialectic of Enlightenment sets the stage for Adorno’s philosophy of the nonidentical, and it foreshadows the intimate connection of the latter to the calamity that Adorno will come to call Auschwitz. The second part of the present book, centered around Negative Dialectic, further explores that connection, and through it the paramount role of suffering in Adorno’s notion of the nonidentical—the suffering of the torturable body, and as its historical paroxysm, the suffering of the victims of the Shoah. I show how Adorno’s negative dialectic counters philosophy’s affirmative essence and the identity thinking it is bound up with by searching for a way to let the “irrational” and its pain express itself in rational thought. I look at Adorno’s critical response to Kantian moral philosophy and explore his dialectic of theory and praxis by examining his turbulent relationship with the German student movement. In the third part, I explore what Adorno intuited as a central pillar in the quest to integrate the nonidentical into reasoning: the aesthetic. I examine the role of aesthetic theory in his negative dialectic, as well as the central role the aesthetic plays in the guise of the form of his writing: style, language, rhythm, syntactic choices. Finally, I look at the role of nature, notably natural beauty and animals, in Adorno’s understanding of aesthetic experience and of the different subject-object relationship the latter adumbrates.

From a formal viewpoint, the present book reflects Adorno’s own constellational approach, which I will say more of in the third part below, inasmuch as it does not follow a linear course in which the arguments build up to a conclusion; rather, the different parts interweave to form a Gewebe [fabric] where each thread takes its full meaning only in constellation with the others. Thus, the excursion on Adorno and the student movement is illuminated by the reflections on Adorno’s solidarity with the torturable body, as is the chapter on his critique of Heidegger; the meditation on childhood is informed by the analysis of Dialectic of Enlightenment; the last chapter on art, where Auschwitz is less prominent, can only be understood in the light of the two preceding ones and their reflections on suffering; etc. While the nonidentical is the centerpiece of this study, it is not the object of inquiry in a conventional sense. “Philosophy is essentially not expoundable”, Adorno wrote in Negative Dialectic, a difficulty that seems particularly true in his case, and that anyone setting out to expound Adorno’s thought will run up against. Rather than a systematic analysis (which neither the nonidentical nor Adorno’s thoughts about it are conducive to), I therefore propose a reflection around the nonidentical in which its meanings and implications gradually crystallize. Through a constellation of analyses stemming from an immanent reading of Adorno’s work, I hope to bring to light the many dimensions of the nonidentical and present a broad exposition of the thought that strives to give it a voice.

Constellations also inform my approach to sources. No essay in Adorno’s work stands on its own, no single work finds its full meaning without drawing from his other writings. Thus, Aesthetic Theory must be read in a constant dialogue with Negative Dialectic and the writings surrounding it. Dialectic of Enlightenment comes into its own in Negative Dialectic, and illuminates the path Adorno embarks on in Aesthetic Theory. The shorter essays, and the university lectures the Adorno archive has fairly recently begun to publish, are invaluable pieces of the puzzle—not mere additions to the major works, but just as crucial as the latter for an understanding of Adorno’s thought. It is in this constellational nexus of a work that spans more than forty years and as many volumes that the centrality of both the notion of nonidentical and the historical caesura of Auschwitz asserts itself. The aspiration of the present book is to show how these two intimately connected centerpieces hold Adorno’s thought together, and how they at the same time, at any given point of his vast work, illuminate the latter and add a dimension to what is written, even where the connection to them is not immediately apparent. They are what gives Adorno’s thought its urgency, its ethical core, and turn it into a praxis in its own right. Written in the shadow of the nonidentical’s suffering, Adorno’s philosophy emphatically demonstrates the interconnection of theory and praxis: just how closely how we think informs and shapes what we think and do; and consequently, the crucial role the critical self-reflection of thought plays in any serious attempt to transform individual and collective action.

Adorno considered self-reflection, the act of theorizing and philosophizing about ourselves and the world we live in, an obligation, particularly for those lucky enough to live in a time and place of material satisfaction and relative peace. “We are experiencing a kind of historical respite [Atempause]”, he told his students in 1965, a chance that “must not be missed”:

And I would say that in this possibility lies for all of us, and particularly for you, a kind of obligation, to really reflect, and not to let the mental [geistige] activity be subordinated to the general hustle and bustle; therein lies something like a moral obligation, that the state of reality puts on you as much as on me. It is certainly not only for spiritual reasons that the world has not been changed, but it probably also hasn’t been changed because it has been too little interpreted. (VND 88–9/58)

More than fifty years later, Adorno’s summons rings no less true. The need for interpretation has hardly diminished, and Adorno’s advice to his students to “seriously reflect” and to “not let the mental activity be subordinated to the general hustle and bustle” has acute relevance in a time of universal distraction, where sound bites and discursive performances tend to crowd out serious reflection, and where digestibility and Like-ability often trump the desire to get to the bottom of things. Meanwhile, the plight of the nonidentical continues unalleviated. Auschwitz has not (yet) repeated itself,¹ but the underlying identity thinking is alive and well. We see it in Muslim bans and in the shootings of unarmed black men, in the persistence of everyday racism and in the rise of populist nationalism, in the disparagement of the Humanities in education and in the growing power of fake news and conspiracy theories. At the core of all these different phenomena lies the same inability to differentiate, to see and value the unique, to question one’s own infallibility, which Adorno links directly to identity thinking. To read contemporary society through the lens of his philosophy of the nonidentical opens up profound insights even into phenomena that he himself did not directly engage with. By reflecting on the impact of our epistemic framework on social life, psychology, ethics, culture and politics, Adorno reveals not only the intimate connection between seemingly separate phenomena, but also shows how deeply rooted they are in the fundamental structure of our engagement with the world, and hence, just how close we are at any given point to falling into the identity trap, even when we believe ourselves safe from its most ugly manifestations. “I am not a racist”—but that the man walking towards me is black is the ...