Theodor W. Adorno (; ; born Theodor Ludwig Wiesengrund; 11 September 1903 – 6 August 1969) was a German philosopher, cultural, and music critic. He was a leading member of the Frankfurt School of critical theory, whose work has come to be associated with thinkers such as Ernst Bloch, Walter Benjamin, Max Horkheimer, Erich Fromm, and Herbert Marcuse, for whom the works of Sigmund Freud, Karl Marx, and G. W. F. Hegel were essential to a critique of modern society. As a critic of both fascism and what he called the culture industry, he authored numerous works—such as Dialectic of Enlightenment (1947), Minima Moralia (1951), and Negative Dialectics (1966)—that strongly influenced the European New Left.

In an intellectual climate shaped by existentialism and logical positivism, Adorno developed a dialectical conception of history and philosophy that challenged the foundations of both, anticipating the divide that would later emerge between the analytic and continental traditions. As a classically trained musician, Adorno studied composition with Alban Berg of the Second Viennese School, influenced by his early admiration for the music of Arnold Schoenberg. Adorno's commitment to avant-garde music formed the backdrop of his subsequent writings and led to his collaboration with Thomas Mann on the latter's novel Doctor Faustus (1947), while the two men lived in California as exiles during the Second World War. Working at the newly relocated Institute for Social Research, Adorno collaborated on influential studies of authoritarianism, antisemitism, and propaganda that would later serve as models for sociological studies the institute carried out in post-war Germany.

Upon his return to Frankfurt, Adorno was involved with the reconstitution of German intellectual life through debates with Karl Popper on the limitations of positivist science, critiques of Martin Heidegger's language of authenticity, writings on German responsibility for the Holocaust, and continued interventions into matters of public policy. As a writer of polemics in the tradition of Friedrich Nietzsche and Karl Kraus, Adorno delivered scathing critiques of contemporary Western culture. Adorno's posthumously published Aesthetic Theory (1970), which he had planned to dedicate to Samuel Beckett, is the culmination of a lifelong commitment to modern art, which seeks to revoke the "fatal separation" of feeling and understanding long demanded by the history of philosophy and explode the privilege aesthetics accords to content over form and contemplation over immersion. Adorno was nominated for the 1965 Nobel Prize in Literature by Helmut Viebrock.

Life and career Early years: Frankfurt Theodor W. Adorno was born as Theodor Ludwig Wiesengrund in Frankfurt on 11 September 1903, the only child of Maria Calvelli-Adorno della Piana (1865–1952) and Oscar Alexander Wiesengrund (1870–1946). His mother, a Catholic from Corsica, was once a professional singer, while his father, an assimilated Jew who had converted to Protestantism, ran a successful wine-export business. His mother wanted her son's surname to include her own, Adorno. Thus, his earliest publications carried the name Theodor Wiesengrund-Adorno. Upon his application for US citizenship, his father's surname, Wiesengrund, was dropped from the name.

His mother and aunt provided a vibrant musical life during his childhood. Maria was a singer who could boast of having performed in Vienna at the Imperial Court, while her sister, Agathe, who lived with them, had made a name for herself as both a singer and pianist. He was not only a precocious child but, as he recalled later in life, a child prodigy who could play pieces by Beethoven on the piano by the time he was twelve.

At the age of six, he attended the Deutschherren Middle School before transferring to the Kaiser-Wilhelm Gymnasium, where he studied from 1913 to 1921. Before his graduation at the top of his class, Adorno was already swept up by the revolutionary mood of the time, as is evidenced by his reading of György Lukács's The Theory of the Novel that year, as well as by his fascination with Ernst Bloch's The Spirit of Utopia, of which he would later write: Adorno's intellectual non-conformism was also shaped by the repugnance he felt towards the nationalism that swept through the Reich during the First World War. Along with future collaborators Walter Benjamin, Max Horkheimer, and Ernst Bloch, Adorno was profoundly disillusioned by the ease with which Germany's intellectual and spiritual leaders—among them Max Weber, Max Scheler and Georg Simmel, as well as his friend Siegfried Kracauer—came out in support of the war. The younger generation's distrust for traditional knowledge arose from how this tradition had discredited itself. Over time, Oscar Wiesengrund's firm established close professional and personal ties with the factory of Karplus & Herzberger in Berlin. The eldest daughter of the Karplus family, Margarete, or Gretel, moved into the intellectual circles of Berlin, where she became acquainted with Benjamin, Bertolt Brecht, and Bloch, each of whom Adorno would become familiar with during the mid-1920s. After fourteen years, Gretel Karplus and Adorno were married in 1937.

At the end of his schooldays, Adorno not only benefited from the rich concert offerings of Frankfurt—where one could hear performances of works by Schoenberg, Schreker, Stravinsky, Bartók, Busoni, Delius, and Hindemith—but also began studying music composition at the Hoch Conservatory while taking private lessons with well-respected composers Bernhard Sekles and Eduard Jung. At around the same time, he befriended Siegfried Kracauer, the Frankfurter Zeitungs literary editor, of whom he would later write:

Leaving grammar school to study philosophy, psychology and sociology at Johann Wolfgang Goethe University in Frankfurt, Adorno continued his readings with Kracauer, turning now to Hegel and Kierkegaard, and began publishing concert reviews and pieces of music for distinguished journals like the Zeitschrift für Musik, the Neue Blätter für Kunst und Literatur and later for the . In these articles, Adorno championed avant-garde music at the same time as he critiqued the failings of musical modernity, as in the case of Stravinsky's The Soldier's Tale, which in 1923 he called a "dismal Bohemian prank." In these early writings, he was unequivocal in his condemnation of performances that either sought or pretended to achieve a transcendence that Adorno, in line with many intellectuals of the time, regarded as impossible. "No cathedral," he wrote, "can be built if no community desires one." In the summer of 1924 Adorno received his doctorate with a study of Edmund Husserl's phenomenology under the direction of the unorthodox neo-Kantian Hans Cornelius. Before his graduation, Adorno had already met his most important intellectual collaborators, Horkheimer and Benjamin. Adorno met Horkheimer through Cornelius's seminars, and Horkheimer subsequently introduced him to Friedrich Pollock.

Vienna, Frankfurt, and Berlin

During the summer of 1924, the Viennese composer Alban Berg's Three Fragments from Wozzeck premiered in Frankfurt, at which time Adorno introduced himself to Berg and mutually agreed the young philosopher and composer would study with Berg in Vienna. Upon moving to Vienna in February 1925, Adorno immersed himself in the musical culture that had grown up around Schoenberg. In addition to his twice-weekly sessions with Berg, Adorno continued his studies on piano with Eduard Steuermann and befriended the violinist Rudolf Kolisch. In Vienna, he and Berg attended public lectures by the satirist Karl Kraus, and he met Lukács, who had been living in Vienna after the failure of the Hungarian Soviet Republic. Berg, whom Adorno called "my master and teacher," was among the most prescient of his young pupil's early friends:

After leaving Vienna, Adorno traveled through Italy, where he met with Kracauer, Benjamin, and the economist Alfred Sohn-Rethel, with whom he developed a lasting friendship, before returning to Frankfurt. In December 1926 Adorno's Two Pieces for String Quartet, Op. 2, was performed in Vienna, providing a welcome interruption from his preparations for the habilitation. After writing the Piano Pieces in strict twelve-tone technique, as well as songs later integrated into the Six Bagatelles for voice and piano, Op. 6, Adorno presented his habilitation manuscript, The Concept of the Unconscious in the Transcendental Theory of the Psyche (Der Begriff des Unbewußten in der transzendentalen Seelenlehre), to Cornelius in November 1927. Cornelius advised Adorno to withdraw his application because the manuscript was too close to his own way of thinking. In the manuscript, Adorno sought to emphasize the epistemological status of the unconscious as it emerged from Freud's early writings. Against the function of the unconscious in both Nietzsche and Spengler, Adorno argued that Freud's notion of the unconscious serves as a "sharp weapon ... against every attempt to create a metaphysics of the instincts and to deify full, organic nature."

Undaunted by his academic prospects, Adorno threw himself once again into composition. In addition to publishing numerous reviews of opera performances and concerts, Adorno's Four Songs for medium voice and piano, Op. 3, was performed in Berlin in January 1929. Between 1928 and 1930, Adorno took on a greater role within the editorial committee of the Musikblätter des Anbruchs. In a proposal for transforming the journal, he sought to use Anbruch to champion radical modern music against what he called the "stabilized music" of Pfitzner, the later Richard Strauss, as well as the neoclassicism of Stravinsky and Hindemith. During this period he published the essays "Night Music," "On Twelve-Tone Technique," and "Reaction and Progress." Yet his reservations about twelve-tone orthodoxy became steadily more pronounced. According to Adorno, twelve-tone technique's use of atonality can no more be regarded as an authoritative canon than can tonality be relied on to provide instructions for the composer.

At this time Adorno struck up a correspondence with the composer Ernst Krenek, discussing problems of atonality and the twelve-tone technique. In a 1934 letter, he sounded a related criticism of Schoenberg:

At this point Adorno reversed his earlier priorities: now his musical activities came second to the development of a philosophical theory of aesthetics. Thus, in the middle of 1929, he accepted Paul Tillich's offer to present a habilitation on Kierkegaard, which Adorno eventually submitted under the title The Construction of the Aesthetic. At the time, Kierkegaard's philosophy exerted a strong influence, chiefly through its claim to pose an alternative to Idealism and Hegel's philosophy of history. Yet when Adorno turned his attention to Kierkegaard, watchwords like "anxiety," "inwardness," and "leap"—instructive for existentialist philosophy—were detached from their theological origins and posed, instead, as problems for aesthetics. As the work proceeded—and Kierkegaard's overcoming of Hegel's idealism was revealed to be a mere interiorization—Adorno excitedly remarked in a letter to Berg that he was writing without looking over his shoulder at the faculty who would soon evaluate his work. Receiving favorable reports from Professors Tillich and Horkheimer, as well as Benjamin and Kracauer, the university conferred on Adorno the venia legendi in February 1931. On the very day his revised study was published, 23 March 1933, Hitler seized dictatorial powers.