By the end of the nineteenth century, the forces of modernity were challenging the Enlightenment tradition of rational optimism.  This chapter discusses the rise of irrationality in Western culture and its expressions in politics, philosophy, science, and art.

Despite a veneer of bourgeois optimism, European society suffered disarray at the turn of the nineteenth century.  The Second Industrial Revolution exacerbated class tensions, thus contributing to the rise of union activism and socialism.  Competing for resources, markets, and status, the major European powers built empires in Africa and Asia, where subject peoples suffered repression and exploitation.  A driving force of imperialism, nationalism became increasingly belligerent, particularly in Germany where it meshed with anti-Semitism, thus setting the stage for the rise of Nazism.

Of all the major states, Britain suffered the fewest political upheavals.  Between 1832 and 1918, Britain gradually extended suffrage to the working classes and women and introduced a variety of social welfare programs.  During the tumultuous Third Republic, French republicans and conservatives vied for control, a struggle that culminated with the Dreyfus affair and its aftermath.  After unification, Germany became a world industrial and military power but remained a semi-autocratic state in which extreme nationalists gained increasing power.  Although Russia westernized significantly under Alexander II, tsarist autocracy persisted, thwarting all efforts of peaceful reform.

In this social and political context, irrationalism came to challenge the Enlightenment tradition.  The major philosophical voice of irrationalism was Nietzsche.  Scorning Enlightenment values, Nietzsche extolled the heroic individuality of the Übermensch, who destroys traditional morality and lives according to self-created values.  Unlike Nietzsche, Freud studied the irrational with a scientific eye, seeing repressed yet powerful drives at the heart of human nature.  In his pessimistic view, civilization and its neuroses are the price we must pay to restrain the id and its appetites.  Irrationalism entered science through modern physics.  Challenging Newtonian principles, physicists including Planck, Bohr, Heisenberg, and Einstein theorized the uncertainty inherent in the structure of the universe.

As philosophy and science broke with the Enlightenment tradition, Modernism challenged inherited modes of artistic expression.  Even more intensely than their Romantic forebears, Modernists rejected received forms and attacked social convention.  In doing so, they strove to liberate their imaginations, plumb the depths of the psyche, and represent intensely subjective points of view.  Surpassing Realism, Modernist writers including Proust, Joyce, and Woolf cultivated introspection, employing techniques such as stream of consciousness and interior monologue to render the hidden reality of the mind.  Like Freud, Conrad explored the dark human drives beneath the surface order of civilization, while Kafka represented the cruel irrationality and caprice that define human existence.  Chopin and Lawrence attacked Victorian sexual mores, equating those with death and disfigurement, and envisioning true fulfillment in unconstrained passion.  In his Naturalist plays, the misogynistic Strindberg explored sexual, class, and family conflicts, turning later to a richly symbolic Modernist style through which he tried to represent tormented realities.  Continuing the tradition of Ibsen, Shaw wrote problem plays in which the characters debate a variety of philosophical, social, and humanitarian issues.

Rejecting Renaissance values, Modernist artists no longer depicted objective reality according rational principles.  Instead, they sought to depict the truth of their imaginative visions.  The Post-Impressionists—including Cézanne, Seurat, Gauguin, and van Gogh—enlarged the expressive possibilities of line and color as they strove to render their subjective perceptions of objects, landscapes, and mystical experiences.  Influenced by Gauguin and van Gogh, the Fauves, led by Matisse, built imaginative worlds from flattened forms, distorted perspectives, and intense, unnatural colors.  Also inspired by Gauguin and van Gogh, Munch and the German Expressionists used bold colors and increasingly abstract forms to convey private feelings of anxiety and isolation.  Taking cues from Cézanne, Picasso pioneered Cubism, exploring with Braque ways to depict successive views of objects simultaneously.  Influenced by Cubism and Marinetti's Futurism, Boccioni sculpted forms designed to capture pure movement through space.

Modernist architecture rejected earlier styles in the search for innovation.  In Europe, Gaudi's Art Nouveau designs emphasized curving organic forms rather than the straight lines of traditional classicism.  In the United States, Sullivan's Chicago School took advantage of the possibilities of structural steel to pioneer the modern skyscraper.  Sullivan rejected ornament, defining a style in which the function of the building dictates its form.  Although Sullivan's designs initially employed classical tripartite composition, they grew increasingly severe, using wide stretches of glass to highlight the steel frame.

Impatient with received conventions, Modernist composers created music that was thematically eclectic, rhythmically complex, and harmonically dissonant.  Led by Schönberg, the Expressionists developed atonal music, defining it according to the twelve-tone system.  Ives drew from various American popular forms, using techniques including tone clusters, polyrhythms, and polytonality to bind these diverse elements into expressive wholes.  Stravinsky's works encompassed most of the tendencies of modern music.  However, he was particularly influential as the composer for the Ballets Russes, writing scores that astonished musicians and audiences alike with their innovative orchestrations, percussive rhythms, and extreme dissonances.

By the turn of the nineteenth century, the Enlightenment tradition was suffering multiple assaults.  Despite widespread optimism about Europe's future, varieties of irrationalism were undermining the orderly, humane world of the Enlightenment.  Awareness of the irrational offered Modernist artists new and exciting resources of expression and spurred modern physicists to develop a compelling alternative to the Newtonian universe.  Extolled by Nietzsche and analyzed by Freud, this irrationalism also fed the ideologies of extreme nationalists who helped unleash unprecedented violence in the twentieth century.