e all feel we know the story of Stephen Hawking: his undergraduate years at Oxford; the shocking diagnosis of motor neurone disease when he was 21 and the slow decline of his physical body for half a century; his two marriages; his research into the nature of black holes that established him as one of the most brilliant scientists of his generation; and of course the publication of A Brief History of Time, which turned him into an icon, the genius in the wheelchair. A number of biographies already exist, and there is a memoir entitled, inevitably, My Brief History, as well as the biopic, The Theory of Everything, in which Hawking is played by Eddie Redmayne. But this latest, highly enjoyable, book is different. What is refreshing is the absence of the usual adulation of an exceptional mind and celebration of triumph over adversity. In their place is a tender account, full of genuine affection, which doesn’t shy away from Hawking’s intense focus, self-centredness, unpredictability and the difficulties faced by his wives and carers. The author, Leonard Mlodinow, is in an almost unique position. A fellow physicist and science writer, he worked closely with Hawking over many years during which they co-wrote two bestselling books: A Briefer History of Time and The Grand Design, the collaboration on and writing of which forms the backdrop for this memoir. For those who have followed Hawking’s career there is a retelling of well-known stories, such as his bets with fellow physicists over certain theoretical predictions, and his views on a final theory of everything, as well as his famous sense of fun and adventure, whether joining Mlodinow for an afternoon of punting on the River Cam or hitching a ride on the famous “vomit comet” to experience zero gravity. Many people, on meeting Hawking for the first time – myself included – felt compelled to fill the awkward silences, while they waited for him to compose his computerised responses. That is, of course, if Hawking deemed it necessary to respond at all, because those who knew him well could understand a great deal by interpreting his facial expressions. He would indicate if he wanted to be shifted slightly in his chair by moving his eyes left or right, then grimacing if it wasn’t quite right and raising his eyebrows and smiling if he felt better. I remember meeting him backstage at the Royal Albert Hall where I was introducing him before he gave a public lecture. I babbled away for a couple of minutes, not knowing the code, before his nurse came to his, and my, rescue. Then I saw his smile and realised I was forgiven. Mlodinow recounts a more surreal first meeting. On arriving in Hawking’s office in Cambridge and greeting him, he watched while the great man’s cheek twitched, a remote sensor built into his glasses translating this into cursor movements and clicks on his computer screen. After a time that must have seemed to confirm Einstein’s theory of relativity, Hawking’s computerised voice uttered one word: “Banana”. Mlodinow was at a loss. It turned out he was addressing his carer, Sandi, who’d been sitting on the couch across the room. Only after she had disappeared to get his snack did Hawking compose the words Mlodinow had expected: “Welcome to DAMTP” (Cambridge’s famous department of applied mathematics and theoretical physics). At one point while writing The Grand Design, Hawking wanted to state, controversially, that “philosophy is dead” – implying that theoretical physics had now replaced it as the means by which we now ask and answer the deepest questions about the nature of reality. Mlodinow wanted to soften this to a more nuanced “as a way of understanding the physical world, philosophy is dead”. But Hawking was adamant. He said the longer sentence was too watered down and “had no punch”. He stuck to his guns and eventually, of course, got his way. He knew that the statement would “piss a lot of people off”, but, Mlodinow says, Hawking was in his way reckless and “liked to cause a stir”. That Hawking was famous for his courage, his stubbornness and his sense of mischief is not new. But we don’t often hear about his vulnerability. Trapped inside his body, he was incapable of doing those simple things that the rest of us so take for granted, like scratching an itch or wiping a bead of sweat. And yet there was no self-pity. Hawking’s book royalties, and subsequent fame, earned him millions – money spent by and large on the entourage of carers he needed. Their relationships with him, as recounted by Mlodinow, were sometimes chaotic, but highlight the banality and ordinariness of the many daily routines that made up the unseen part of his life. These stories, told with humour and fondness, mean that I feel I now know Hawking a little better. I still don’t fully understand his theory of black hole radiation, but I won’t go into that now. • Stephen Hawking is published by Allen Lane (£20). To order a copy go to guardianbookshop.com. Delivery charges may apply.