The world’s most charismatic mathematician | Siobhan Roberts

John Horton Conway is a cross between Archimedes, Mick Jagger and Salvador Dali. For many years, he worried that his obsession with playing silly games was ruining his career - until he realised that it could lead to extraordinary discoveries

On a late September day in 1956, John Horton Conway left home with a trunk on his back. He was a skinny 18-year-old, with long, unkempt hair - a sort of proto-hippie - and although he generally preferred to go barefoot, on this occasion he wore strappy Jesus sandals. He travelled by steam train from Liverpool to Cambridge, where he was to start life as an undergraduate. During the five-hour journey, via Crewe with a connection in Bletchley, something dawned on him: this was a chance to reinvent himself.

In junior school, one of Conway's teachers had nicknamed him "Mary". He was a delicate, effeminate creature. Being Mary made his life absolute hell until he moved on to secondary school, at Liverpool's Holt High School for Boys. Soon after term began, the headmaster called each boy into his office and asked what he planned to do with his life. John said he wanted to read mathematics at Cambridge. Instead of "Mary" he became known as "The Prof". These nicknames confirmed Conway as a terribly introverted adolescent, painfully aware of his own suffering.