How can a driver who has undergone a 46-g impact race the very next day at speeds up to 335kmh?
Within the answer lies a testimony to the incredible progress that Formula One has made in the realm of safety.
When Carlos Sainz's Toro Rosso was seen buried in the barriers in the run-off area to Turn 13 during the Russian Grand Prix's final practice session on Saturday morning, everyone feared the worst.
Coming through the long left-handed approach to Turn 13, where cars have just peaked at 335kmh in eighth gear, he had lost control while braking hard for the second gear right-hander that is Turn 13 and is usually taken at 105kmh in second gear.
He was experimenting with the brake bias, juggling how much retardational effort he wanted between the front wheels and the rear ones, when his Toro Rosso oversteered left into the outer wall, smashing its left-front suspension. After that the 21 year-old rookie was simply a passenger.
It was one of those deeply unpleasant moments in racing when everything goes quiet, the red flag flies and the television cameras look everywhere but where everyone desperately wants them to look. When you hold your breath and pray.
Today, F1 cars are immensely strong. That's because they are built from advanced carbon-fibre composites, but also because every chassis has to pass crash tests introduced many years ago - and continually upgraded
- by the FIA.
Thankfully, this time the news was good. Better than good, actually. Sainz was eventually freed from his car, whose survival cell was intact despite the very heavy impact, and was stretchered conscious, and giving a cheerful thumbs up, to the medical centre.
Then he was airlifted to the Sochi4 Hospital for the mandatory medical checks and scans, and late in the afternoon his team boss Franz Tost revealed that he had been completely uninjured.
The F1 paddock could breathe again after the miraculous deliverance.
On Sunday morning, the Spaniard passed the mandatory International Automobile Federation (FIA) medical tests conducted by the medical delegate and the chief medical officer, and was cleared to race if he wanted to.
That was like asking an alcoholic if he fancied a beer. Sainz is a racer, and couldn't wait to get back into a car which, incredibly, his team had rebuilt to pristine condition overnight.
It's only when these things happen, when things go wrong, that you realise just how technically brilliant this sport is, and how resilient are the people inspired to drive such cars.
So how did that deliverance happen? Thirty-five years ago, a similar accident befell the Swiss driver Clay Regazzoni at Long Beach, and he was left paralysed.
Today, F1 cars are immensely strong. That's because they are built from advanced carbon-fibre composites, but also because every chassis has to pass crash tests introduced many years ago - and continually upgraded - by the FIA.
Among other things, these specify resistance to very significant frontal, side and overhead impacts, and no car is cleared to race unless its chassis has satisfied these criteria.
But in this instance credit is also due to the new system of safety barrier called Tecpro, that in places has superseded traditional steel Armco barriers or stacks of tyres wired together to provide a structure that will deform progressively and absorb impact.
Tecpro barriers comprise a polyethylene-metallic sheet combination, with each individual barrier piece made from variable density foam, with a reinforcing metallic sheet placed at its centre.
Each one is 1.37m long, 1.22m high and 61cm wide, and weighs 118kg. These sections can be bound together with high-strength nylon belts to create barriers of the desired length.
There was some debate among the drivers after the barrier that Sainz hit lifted sufficiently for his car to go beneath it, but it did its job and played a strong role in safeguarding him.
Lewis Hamilton's 42nd race victory and Mercedes' last-minute success in securing their second consecutive world championship for constructors were serious news stories, but amid all the celebrations Sainz's parable of technical ingenuity and the strength of the human spirit was perhaps the most uplifting aspect of F1's second visit to Sochi.