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William James Sidis is often regarded as the smartest man to have ever lived, with claims about his extraordinary IQ making him a legendary figure. His intellectual prowess is said to have surpassed that of geniuses like Albert Einstein and Elon Musk. However, much of what is known about Sidis comes from fragmented stories and claims—many of which are disputed.
So, who was William James Sidis, and how much of his reputed genius can be confirmed?
A Prodigy Born into a High-Pressure Environment
Born on April 1, 1898, in New York City to Jewish immigrants from Ukraine, William Sidis seemed destined for intellectual greatness. His father, Boris Sidis, was a prominent psychiatrist and a pioneer in abnormal psychology, while his mother, Sarah Sidis, was a physician. Boris Sidis was determined to nurture his son’s talents and applied his theories of child-rearing, pushing William to his intellectual limits from an early age.
According to family accounts, William could read by 18 months and reportedly devoured complex texts like The New York Times at a very young age. By the time he was 8, he allegedly spoke eight languages, including Latin, Greek, French, Russian, and Hebrew, and had invented his own language, “Vendergood.” He was eventually accepted into Harvard University at the age of 11, setting a record as the youngest person to attend the prestigious institution.