Paul Erdős: The Wandering Genius Who Loved Only Numbers

The Man With No Home

He owned no house. He had no job — not in the traditional sense. He carried everything he needed in two half-empty suitcases and a plastic bag. He would show up at a colleague’s door, announce “my brain is open,” and begin working on mathematics. When the problems were solved or the host’s patience was exhausted, he moved on to the next doorstep, the next country, the next problem.

Paul Erdős (1913–1996) was the most prolific mathematician of the twentieth century, the most collaborative scientist in the history of the discipline, and one of the most eccentric human beings ever to walk the earth. He published over 1,500 papers, collaborated with more than 500 co-authors, and spent his entire adult life as a mathematical nomad — a wandering scholar in a tradition that stretches back to the rabbinic sages of antiquity.

Budapest and Loss

Erdős was born in Budapest on March 26, 1913, into a Jewish family shaped by tragedy. On the day of his birth, his two older sisters died of scarlet fever. His mother, Anna, traumatized by the loss, became intensely protective of her surviving child — so protective that Erdős did not butter his own bread until he was twenty-one.

Both parents were mathematics teachers. His father, Lajos, was captured by the Russian army during World War I and spent six years in a Siberian prison camp, where he taught himself English by reading — his only available books were in that language. When he returned, he spoke English with a Russian accent for the rest of his life.

Young Paul was a prodigy. At four, he could multiply three-digit numbers in his head. At twenty-one, he earned his doctorate from the University of Budapest. That same year, 1934, with antisemitism rising in Hungary, he left for a postdoctoral fellowship in Manchester, England.

A Nomad of Numbers

Erdős never returned to Hungary permanently. During World War II, four of his mother’s five siblings were murdered in the Holocaust. His father died before the war. These losses deepened his already unconventional approach to life: possessions meant nothing, institutions meant nothing, only mathematics and human connection mattered.

He spent the rest of his life traveling — from university to university, country to country, sleeping on couches and in guest rooms, living on lecture fees and modest prizes. He gave away almost all his money, often to students or to strangers who needed it. He ate simply, slept little, and worked constantly, fueled by coffee and amphetamines (the latter a habit he maintained for decades despite friends’ concern).

The Art of Collaboration

What made Erdős unique was not just his productivity but his collaborative method. Before Erdős, mathematics was largely a solitary pursuit. Erdős turned it into a social activity. He would arrive at a university, ask what problems people were working on, and start solving them together — at breakfast, on walks, in the middle of the night.

His enthusiasm was infectious. He called children “epsilons” (the mathematical term for small quantities). He called women “bosses” and men “slaves.” He referred to the United States as “Sam” and the Soviet Union as “Joe.” He called God “the Supreme Fascist” — not out of malice but from a quirky conviction that a deity who hid the most beautiful proofs was being deliberately difficult.

He believed that the most elegant mathematical proofs existed in a celestial book — “The Book” — and the highest compliment he could pay a proof was to say it was “from The Book.”

The Erdős Number

Erdős’s vast network of collaborators gave rise to the concept of the Erdős number — a playful measure of collaborative distance. If you co-authored a paper with Erdős, your Erdős number is 1. If you co-authored with someone who worked with Erdős, your number is 2. Albert Einstein has an Erdős number of 2.

The concept has become a cultural phenomenon in mathematics and beyond, symbolizing the deeply interconnected nature of scientific knowledge.

Mathematics and Morality

Despite his atheism, Erdős’s life had a profoundly moral quality. He was generous to a fault, giving money to anyone who needed it. He championed young mathematicians, especially those from countries with limited academic resources. He was kind, gentle, and genuinely interested in other people — a combination not always found in mathematical genius.

His Jewish identity was cultural rather than religious, but the pattern of his life — wandering, questioning, valuing learning above material wealth — echoed ancient Jewish archetypes. He was, in a sense, a modern-day itinerant scholar, carrying his Torah of numbers from town to town.

Legacy

Erdős died on September 20, 1996, at a mathematics conference in Warsaw — working, as always, until the very end. He was eighty-three. He left behind no house, no fortune, and no family — only the most extraordinary body of mathematical work in modern history and a global community of collaborators who still speak of him with love.

His epitaph, which he composed himself: “I’ve finally stopped getting dumber.” It was a joke, of course. But for a man who believed that the purpose of life was to understand the universe one theorem at a time, it was also a kind of prayer.