In June 1903, the young Jewish-Austrian philosopher Otto Weininger published his first book, Geschlect und Charakter (Sex and Character), a long, dense, obsessively researched work of hysterical misogyny and anti-Semitism that fell virtually stillborn from the presses. Exhausted and destabilised by feelings of guilt and inauthenticity, Weininger had melodramatically speculated, at the time of publication, that three possibilities awaited him—“the gallows, suicide, or a future so brilliant that I dare not think about it”. In the event, a few months later, Weininger rented a room in the house in SchwarzspanierstraBe, Vienna, where his supreme hero, Beethoven, had died. He wrote to his family to say that he planned to kill himself, and then, that evening, shot himself in the chest. His brother arrived at the house, having received the letter the next morning, to find Otto dying on the floor.

At the age of 23, Weininger had stubbornly confirmed the truth of his own prediction by choosing death over the brilli ant future for which he so desperately longed. Yet, in renouncing the world, he was merely following the logic of his own argument as expressed in Sex and Character: that, if one cannot be great, one should not live at all.

So that, everyone thought, was that. However, as word about Weininger’s suicide spread through the salons of Vienna, a cult began to develop around him and his curious book. Reviews of Sex and Characterbegan slowly to appear; his aphorisms and gnomic utterances were hastily collected by his friends and published in a book called On Last Things; the satirist Karl Kraus and Sigmund Freud declared themselves admirers of the disturbed intellectual, and an assortment of thinkers, including the young Ludwig Wittgenstein, Oswald Spengler, Adolf Hitler and Franz Kafka, read Weininger with fervid attention. Riding a wave of morbid curiosity, Sex and Character soon became a defining text of Hapsburg Vienna, over which a sad imperial twilight was settling even as the population of the city, swelled by a veritable Babylon of polyglot migrants from across the empire, was expanding exponentially, thus rendering society dangerously unstable.

To be alive at the end of the 19th century in Vienna was to experience social life as a maelstrom. As the old order slipped into decline, new ideas flourished; crisis, it seemed, inspired creativity. People were at once energised and enraged by anti-Semitism, Zionism, pan-German fanaticism and feminism, by the theories of Freud, the architecture of Adolf Loos and by the visual art of Gustav Klimt and Egon Schiele. Degeneracy was perceived as being everywhere apparent in fin fin-de-siecle Vienna, its manifestation identified in anything from the emancipation of women and the popularity of psychoanalysis to the proliferation of prostitution. “We are now fully infected by serious popular mental illness, a sort of black plague for degeneration and hysteria,” wrote Max Nordau, a German-speaking Jew from Hungary. Vienna, as Kraus remarked, was becoming the “laboratory of world destruction”.

If anyone was a victim of Nordau’s plague, it was Otto Weininger, who was pathologically preoccupied with decay and whose work seethed with the anxieties of his age. Modern life terrified him. He longed, like a Nietzschean fanatic, to break free from the enslaving chains of mediocrity, believing that the exceptional individual always created his own values. For Weininger, life amounted to a stark dichotomy: greatness or nothingness.

To read Sex and Character is to emerge as if from a whirlwind: shaken, disturbed, but exhilarated by the precocity and absolute singularity of Weininger’s vision. It is difficult to think of another work that is, in equal parts, quite so clumsy, brilliant and repellent. The book is opaque. It is sometimes atrociously written (I have German friends who read passages aloud to themselves, so hilariously absurd do they find Weininger’s style and ideas). And yet there is something moving about Weininger’s struggle to turn what the philosopher Ray Monk has called his “bigotry and self-contempt” into a politics for living. As Chandak Sengoopta writes, in this fascinating study, Weininger planned, in his book, no less than “to analyse the differences between male and female from all perspectives—biological, cultural, metaphysical—and to base a…critique of modern civilisation on that analysis”.

Weininger believed that the self is a microcosm of the world, but that, at the same time, the empirical self, like the world, is an infinite mystery; that we can never know who we are in all our essential complexity. He believed, too, that all human beings are biologically bisexual, combining male and female characteristics, and he discusses men and women not as individuals, but as ideal, Platonic types. Woman, he says, is weak, illogical, amoral, instinctual, feeble-minded and obsessed with sex. Woman has no autonomous self. Man, by contrast, is rational, strong, moral, engaged with the world and “free from all fetters of necessity, and from all taints of the earth”.

Employing the rhetoric and ideas of science and medicine, Weininger further divides Woman into two archetypes: mother and whore. The prostitute, he writes, is motivated not by economic necessity, but by pure desire. She is no more than a sexual being, a monolith of desire. The mother is also a sexual being, but she uses sex as a means to an end—that of producing a child and uniting Man with Woman—whereas, for the prostitute (whom Weininger eccentrically defines as any woman with a recreational interest in sex), sex is an end in itself.

For Weininger, sex is an abomination: it locates Man in the world of the senses when the duty of every individual is, in fact, to transcend the merely empirical world as he seeks a higher love—the love of self. “In love, man is only loving himself. Not his empirical self, not the weakness and vulgarities, not the failings and smallnesses which he outwardly exhibits; but all that he wants to be, all that he ought to be, his truest, deepest, intelligible nature, free from all the fetters of necessity, from all taint of the earth.”

Weininger is a Kantian idealist. He sees the world of the senses—the world of appearances—as no more than a cruel distraction. What matters is noumena, the world that lies transcendentally beyond appearances, and also the contemplation of permanent generalities—goodness, truth, beauty. But only through renouncing transient pleasures—sex, the body, that which is most “feminine” or “Jewish” in our natures—can an individual find dignity, find the divine in himself. And the man most likely to achieve such an elevated state of grace is the genius—the Beethoven or Wagner—for whom life is a kind of duty to achieve all that his potential will allow.

The most female of men, he adds, is the cosmopolitan Jew, who, in his rootlessness and degeneracy, is “saturated in femininity”. (Weininger, who later converted to Protestantism, reminds us in a footnote of his own Jewish origins.) Christ was great because he “conquered in himself Judaism, the greatest negation, and created Christianity, the strongest affirmation and the most direct opposite of Judaism”. Hitler, an admirer, described Weininger as a “good Jew”, who “killed himself on the day when he realised that the Jew lives upon the decay of peoples”.

Was Weininger mad? Well, no one who met him could ever quite forget the strange intensity of his personality, or quite comprehend the mania of his ideas. Freud, after reading an early draft of Weininger’s thesis, recommended that he spend a decade gathering data to support his generalisations. “The world wants evidence, not thoughts,” he told him. (Freud later conceded that Weininger was blessed with a “touch of genius”, but thought that he was “sexually deranged” and that, “being a neurotic, he was completely under the sway of his infantile complexes”.) Weininger’s postdoctoral tutor, Frederich Jodl, who had urged his student to clarify his ideas, complained of how they had assumed “monstrous” forms in the published treatise, and that his “soul is a riddle to me”.

One suspects that Weininger was a riddle even to himself. He was an outstanding student at Vienna University, a talented linguist and rigorous conversationalist. “Otto was a passionate thinker,” one of his friends said, “the prototype of the thinker.” There has been speculation that Weininger’s peculiar views were rooted in childhood trauma, but there is no evidence to suggest that he was sexually abused. Nor is there any evidence that he ever had sexual relations with women, which has led some to conclude, inevitably, that he was a guilty homosexual.

Influenced by the anti-Semitic pamphlets of Houston Stewart Chamberlain, Wagner’s English son-in-law, Weininger declared, after a lonely period of intense study, that he was becoming interested in ethics and logic, which he saw as one and the same: “All of ethics is conceivable only along logical lines, and all of logic constitutes an ethical law.” So it is immoral, then, to think illogically—as if Weininger himself was a model of rational thought!

Nowadays, Weininger is ridiculed as being no more than a dangerous fanatic, but Sex and Character remains a compelling document of a disturbed age. As Monk explained in his marvellous biography of Wittgenstein, and this book reminds us, Weininger is worth reading because, as Sengoopta writes, some of “the most significant intellectual and cultural currents of the age ripple through his brief life”. Indeed, to read Weininger is to be confronted once again with that great crisis culture of Musil, Freud, Klee, Kraus and Schnitzler (on whose novella, Dream Story, the director Stanley Kubrick based his last film, Eyes Wide Shut). A culture that, in time, proved indeed to be the laboratory of world destruction.