He was about four when he first drove, on an unpaved street in the Santana district of northern São Paulo, in a little kart built for him at his father’s metalworks. The family called him Beco. At 13, the youngest age allowed, he won his first official race, at the kart track beside Interlagos, and he raced karts for nine more years: champion of South America, twice champion of Brazil, twice runner-up in the Karting World Championship and never its winner.
In 1981, aged 20 and newly married, he went to England, and in his first season in cars he won both the Formula Ford 1600 championships he entered. Then he gave up racing and went home to join his father’s business; within months he was back. Somewhere in the next two seasons he stopped racing as da Silva, a name as common in Brazil as Smith is in Britain, and took his mother’s: Senna. In 1982 he won 22 races and two Formula Ford 2000 titles. In 1983 he won the British Formula 3 Championship after a summer-long fight with Martin Brundle, and that November the Macau Grand Prix, the first held for Formula 3 cars.
His first Grand Prix was in Brazil, at Jacarepaguá, in March 1984, in a Toleman; his last, in a Williams, was at Imola, in the San Marino Grand Prix of May 1994. Between them came three seasons with Lotus and six with McLaren, and three world championships, in 1988, 1990 and 1991, each of them settled at Suzuka.
When Denis Jenkinson of Motor Sport asked him in 1989 how he approached a qualifying lap, he tapped his forehead. At Toleman, before cars carried data recorders, his engineer found that he could recall every lap afterwards, even the engine revs out of every corner; at McLaren a debrief could run for two hours, setting by setting, corner by corner. Jenkinson noticed that where onlookers measured the gap to the car in front in seconds, he measured it in distance.
He could be ruthless. At Suzuka in 1990, with the title in reach, he drove into Alain Prost’s Ferrari at the first corner, and a year later he admitted that he had lined up intending to do it if Prost got away first. He could be generous. At Spa in 1992 he stopped his McLaren in practice and ran across the track to Érik Comas, unconscious in his Ligier, switched off its engine and held his head until the doctors came; Comas later credited him with saving his life. The people around him saw both sides.
He was a believer. Brought up a Catholic, he came back to his faith, he said, after a crisis that reached its peak at Monaco in 1988, and a Bible travelled with him in the small case he kept at his side. Of the last lap at Suzuka that October, the lap that made him champion, he said: “I saw God”.
Six months after Imola, in November 1994, his sister, Viviane, founded the Instituto Ayrton Senna, to do what he had asked of her for the children of Brazil, and it is still at work in the country’s schools. Polled by Autosport in 2009, 217 Formula One drivers voted him the greatest of them all.