When you think of the great minds who have shaped Western thought, you probably picture them hunched over dusty tomes, wrestling with questions about reality, knowledge, and morality. Yet many of these intellectual giants also harboured some truly eccentric fixations. Below we dive into 10 odd obsessions of famous philosophers, each one as surprising as the ideas they championed.
10 Odd Obsessions In Philosophy
10 Eyed Ladies
The modern philosophical father, René Descartes (1596–1650), counted powerful women such as Queen Christina of Sweden and the exiled Princess Elizabeth of England among his close acquaintances. Yet his private life told a different tale. Descartes never wed, fathered a single illegitimate daughter with a housemaid, and, intriguingly, his early adulthood was dominated by an attraction to women with crossed eyes.
In a letter to Queen Christina, Descartes reflected on this seemingly irrational draw, tracing it back to a youthful infatuation with a peer who happened to be slightly cross‑eyed. He wrote, “I loved a girl of my own age…who was slightly cross‑eyed; by which means, the impression made in my brain when I looked at her wandering eyes was joined so much to that which also occurred when the passion of love moved me, that for a long time afterward, in seeing cross‑eyed women, I felt more inclined to love them than others, simply because they had that defect; and I did not know that was the reason.”
Descartes concluded that this early crush left a permanent imprint on his psyche, operating beneath reason. In true philosophical fashion, he exercised his free will to overcome the subconscious pull, attempting to purge the irrational fascination.
9 Albert CamusFear Of Early Demise
The celebrated existentialist Albert Camus (1913–1960) emerged from a destitute Algerian household lacking basic utilities. His stern grandmother wielded a bullwhip to maintain order, and despite such hardships, Camus earned a scholarship, survived a bout of tuberculosis at seventeen, and published works before even entering university.
Nevertheless, Camus was haunted by a persistent dread that he would die young. He confided to a girlfriend that he “sensed evil floating in the air.” This anxiety manifested in an obsession with mortality: he kept a suicide note written by a friend of Leon Trotsky’s in his pocket and begged an American girlfriend to send him copies of Embalmer’s Monthly magazine.
Driven by a blend of pessimism and fear, Camus felt compelled to finish his literary legacy before his imagined early death. Even the Nobel Prize, which he won, felt like a grim omen, as he believed it marked the end of a career. The pressure intensified until his fatal car crash on January 4, 1960, at the age of 46, confirming his worst fears.
8 Immanuel KantRigid Schedule
For Immanuel Kant (1724–1804), obsession was not merely a trait but a way of life. While often remembered for his hypochondria, Kant’s most striking fixation was his meticulously regimented daily routine. After purchasing a home in 1783, he instituted a strict timetable that he adhered to until his death.
Each day began just before five o’clock with a cup of tea and precisely one pipe. He then devoted the morning to lectures and writing until his teaching duties commenced at seven. After his lectures concluded at eleven, he returned to his studies until a one‑hour lunch at one o’clock.
Post‑lunch, rain or shine, Kant embarked on his famed hour‑long stroll through Konigsberg, a walk so predictable that neighbors allegedly set their clocks by it. The route later earned the name Philosophengang, or “The Philosopher’s Walk.”
Following the promenade, Kant might chat briefly with a friend before resuming his scholarly pursuits at home, reading until ten at night before finally retiring to bed.
7 Soren KierkegaardFamily Curse
Before Søren Kierkegaard (1813–1855) turned twenty‑five, five of his siblings and both parents had already passed away. Adding to the gloom, his father confessed that a curse—born from a youthful blasphemy—had doomed the family to watch all children die before him.
Kierkegaard internalized this grim prophecy, believing he, too, was fated for an early demise. This conviction spurred him to write prolifically, attempting to articulate everything before his anticipated death. He prefaced an early work, composed shortly after his father’s passing, with a poignant quotation from *King Lear*: “A guilt must weigh on the entire family, God’s punishment must be upon it; it was meant to disappear, expunged by God’s mighty hand, deleted like an unsuccessful attempt.”
The philosopher’s dread proved prophetic: he succumbed in 1855 at the age of 42, confirming the family’s tragic narrative.
6 Karl MarxFrantic Idea Generation
Karl Marx (1818–1883), co‑author of *The Communist Manifesto*, was a towering influence on twentieth‑century thought, yet his personal life resembled a whirlwind of chaos. Financial hardship—exacerbated by his and his family’s expulsion from France due to his political writings—combined with a volatile temperament to produce a pattern of intense, burst‑like productivity followed by periods of exhaustion, illness, and missed deadlines.
Marx’s inner turmoil manifested most vividly in his compulsive idea‑generation method. While working, he would jot an idea, then rise and pace frantically around his desk. When inspiration struck again, he would hurriedly sit, scribble the new thought, and repeat the cycle. This frenetic rhythm often left him collapsing from fatigue after a long day.
5 Friedrich NietzscheFruit
At twenty‑four, Friedrich Nietzsche (1844–1900) secured the Chair of Classical Philology at the University of Basel, quickly establishing himself as a prolific writer and respected scholar. Yet his life was plagued by a cascade of medical maladies—chronic headaches, persistent vomiting, and a painful digestive disorder—that drove him to experiment with a myriad of remedies and diets.
Ironically, Nietzsche’s fixation on fruit may have aggravated his gastrointestinal woes. According to the innkeeper at the Alpine Rose, where Nietzsche lodged in 1884, his daily fare consisted of a beefsteak for breakfast followed by fruit for the remainder of the day. He sourced fruit both locally and from Italian vendors, and friends even shipped him whole baskets.
His fruit consumption was prodigious: on several occasions he devoured nearly three kilograms (about 6.5 lb) of fruit in a single day, a habit that likely intensified his digestive discomfort.
4 VoltaireConstant Need For Coffee
Voltaire (1694–1778), a luminary of the Enlightenment, is celebrated for his razor‑sharp wit and satirical brilliance. Yet his intellectual vigor was fueled by an extraordinary coffee habit. Whether at home or at Paris’s Café de Procope, Voltaire guzzled between twenty and forty cups of coffee each day.
He loved the brew so much that he ignored his physician Theodore Tronchin’s advice to cut back. Instead, he paid lavish sums to import luxury coffee beans for personal consumption.
A famous quotation often linked to Voltaire—“It may be poison, but I have been drinking it for sixty‑five years, and I am not dead yet”—is actually misattributed. Scholars such as William Harrison Ukers argue that the line belongs to Bernard Le Bovier de Fontenelle, who lived longer than Voltaire. The authentic version reads, “I think it must be [a slow poison], for I’ve been drinking it for eighty‑five years and am not dead yet.” Given Voltaire’s death at eighty‑four, the evidence supports Fontenelle’s authorship.
3 Georg Wilhelm Friedrich HegelHis Favorite Clothes
Aside from the tragic loss of his mother when he was thirteen, Georg Wilhelm Friedrich Hegel (1770–1831) enjoyed a relatively uneventful upbringing filled with books. His early adult years saw him studying at a seminary, writing, and tutoring an aristocratic Bern family. By his mid‑forties, he was married, fathered children, and edited the respected literary journal *Heidelberger Jahrbucher*.
Even the most conventional philosophers harbor quirks, and Hegel’s was his choice of nightwear. He habitually wore his nightgown over daytime attire, topped with an oversized black beret. A friend’s surprise visit once revealed Hegel shuffling through a mountain of papers, draped in his nightgown and beret.
This eccentric ensemble was immortalised by lithographer Julius L. Sebbers, who depicted Hegel in his study wearing the same garb. Hegel reportedly loathed the portrait, prompting his wife to note that he disliked it because it resembled him “a bit too much.”
2 Paul SartreFear Of Sea Creatures
Jean‑Paul Sartre (1905–1980) was an indefatigable writer and activist, championing figures like Karl Marx, Fidel Castro, and Che Guevara. Though he famously refused the Nobel Prize, Sartre’s intellectual confidence was undercut by an irrational dread of crustaceans and other marine life.
A childhood painting of a claw emerging from the ocean left a lasting scar. Consequently, Sartre developed an obsessive fear of sea creatures. He once suffered a panic attack after swimming in the Riviera with his longtime partner Simone de Beauvoir, convinced a gigantic octopus would erupt from the depths and drag him under.
His terror even manifested in hallucinations: after ingesting a mind‑altering drug, Sartre reported seeing lobsters trailing him everywhere. This phobia seeped into his literary work, appearing in titles such as *The Condemned of Altona*, “Erostratus,” and *Nausea*.
1 Arthur SchopenhauerHis Poodles
Arthur Schopenhauer (1788–1860) hailed from a well‑off family, yet homelessness became a recurring theme in his life. As an intellectual wanderer, he felt detached from place and person, even regarding his birthplace of Danzus as irrelevant after Prussia annexed it when he was five.
Following his father’s death, Schopenhauer struggled to form attachments, even toward his own mother. This profound alienation manifested in a peculiar companionship: a steady stream of poodles. From his school days until his death, he owned numerous poodles, all christened “Atma” and affectionately nicknamed “Butz.”
The name “Atma” derives from a Hindu concept in the *Bhagavad Gita* signifying the inner self or soul. Schopenhauer believed each poodle embodied the ultimate reality of “poodle,” rather than being distinct individuals. In his view, the dogs represented a transcendent essence rather than mere pets.