A Childhood Beyond Comprehension
On April 1, 1898, William James Sidis was born in Boston to Boris and Sarah Sidis, Ukrainian Jewish immigrants who fled antisemitic violence in the Russian Empire. From an early age, his extraordinary abilities stunned those around him. By six months, he could recognize letters and shapes.
At 18 months, he read the New York Times. By age five, he had written several books on anatomy and grammar. By eight, he spoke eight languages fluently, including Latin, Greek, German, and Russian, and even invented his own language, Vendergood. The media quickly dubbed him a “boy genius,” portraying him as a future scientific revolutionary, though his remarkable intellect came with social challenges.
Harvard at 11: Brilliance and Isolation
In 1909, at just 11 years old, Sidis became the youngest person ever to enroll at Harvard University. He gained widespread attention after delivering a lecture on four-dimensional geometry to Harvard’s Mathematics Club at age 12, astonishing professors and students alike.
However, life at Harvard was far from easy. Older classmates mocked him, and he faced bullying and social exclusion. Lacking interest in sports, romance, or parties, he struggled to connect with peers. Despite these challenges, he graduated cum laude at 16, expressing a strong desire for privacy and a life away from the public eye.
A Reluctant Scholar and Political Activist
After Harvard, Sidis briefly taught mathematics at Rice University at age 17 but resigned after eight months due to continued ridicule from students. He then enrolled at Harvard Law School but did not complete his degree. In the following years, he became involved in socialist and anti-war movements.
In 1919, he was arrested during a May Day protest in Boston and nearly imprisoned for refusing to register for the draft during World War I. Around this period, he developed a close but unfulfilled attachment to Martha Foley, a young activist, keeping her photograph with him until his death.
Retreat from Fame and Final Years
Sidis spent the 1920s and 1930s living quietly under pseudonyms, working menial jobs as a clerk, factory operator, and comptometer operator. Whenever his identity became known, he would resign and move elsewhere. He continued writing prolifically, publishing works on topics from cosmology to Native American history, including his 1925 book The Animate and the Inanimate.
Despite his efforts, most of his writings went largely unnoticed. By the 1940s, his health had deteriorated due to high blood pressure and weight gain. On July 13, 1944, Sidis was found unconscious in a Boston boarding house after suffering a massive stroke and died shortly afterward at the age of 46.
On July 13, 1944, William James Sidis was found unconscious in a Boston boarding house and died shortly after.
Known for an IQ estimated between 250 and 300, his genius drew global attention.
His journey spanned early fame, retreat from public life, and lasting… pic.twitter.com/GsLftL36jG
— Fascinating True Stories (@FascinatingTrue) August 25, 2025