Replace the commas in the subtitle of this book, ‘Thomas Young, the Anonymous Polymath who Proved Newton Wrong, Explained How We See, and Deciphered the Rosetta Stone Among Other Feats of Genius’, with exclamation marks, and it reads like the title of a Gillray cartoon or the patter of a circus huckster. The problem we have with polymaths, as Andrew Robinson points out in his introduction, is that they do seem too good to be true. When it comes to Isaiah Berlin’s famous distinction between thinkers — hedgehogs, who know one big thing, and foxes, who know many things — we are generally more comfortable with the hedgehogs. Or rather, preferring to pin thinkers down into easily memorable categories, we will foxes into hedgehogs. The foxes, with their wide-ranging intellectual curiosity and manifold talents excite our suspicion. Perhaps they are plausible quacks; perhaps they force us to acknowledge our own blinkered specialisms.
Thomas Young, with his achievements in optics, physics, medicine, philology, life insurance and mechanics (among other things), was a remarkable figure in the early 19th century; he now has the biography he deserves. He was elected to the Royal Society at the tender age of 21. In his late twenties his theory of optics in the eye led to researches which demonstrated that light acted as waves, not, as Newton had said, a stream of corpuscles. In his forties he contributed 63 articles to the supplement of the Encyclopaedia Britannica on subjects as diverse and complicated as bridges, ancient Egypt and tides; at the same time he was making the first moves in the unlocking of the riddle of the Rosetta Stone. And these are just a few of the things that Young managed to cram into his life. He died in 1827, aged just 56. The list of his achievements is enough to make the reader feel dizzy and at least a little inadequate; it is a problem for the biographer as well.
It would be too easy to eulogise such a character. In another author’s hands, Young might have been treated with reverential awe. But Robinson is an experienced enough writer to give the case against his subject as well as attempting to justify the big claims of the title. In his own time and ever since Young has been accused of spreading himself too widely to make a real mark in any of his fields. As one friend complained to Young, it was a matter of regret that his versatility was such that he was forever being pulled ‘from mathematics to Greek philosophy and from that to medicine’ so that he was unable to bring his discoveries to a ‘pitch of perfection’. But, as this book shows, Young is a key figure in the history of science. It was just that he did not boast about his discoveries, or indeed explain them with the precision required of a rigorous discipline; it was left to later generations to elucidate Young’s insights.
There would be no research grant for Young today. As he said, he preferred ‘general investigations to particular applications’, but doubted whether the world would have benefited had he confined himself to a narrower sphere. He would have found it impossible to do so. Fortunately, he had the rare luxury to go where his mind led him. I take the sobriquet ‘The Last Man Who Knew Everything’ to apply to his methodology rather than to a miraculous feat of memory and reading. For in every aspect of his researches Young returned to first principles. He had a prodigious memory and the ability to hold a multitude of competing theories in his mind at once. He cleared his mind of the cant and received opinions and sacred tenets of science and medicine that imprisoned the thinking of many of his contemporaries. He was not in thrall to Newton (as most scientists were) and made his own way to rethinking the theory of light; similarly, in deciphering the Rosetta Stone he read all there was to read on the subject and sorted the specious thinking and unquestioned conventions that had grown up around hieroglyphics over the centuries to apply his own logical mind afresh to philology. It was unthinkable that he should clamber over stones or delve under pyramids in Egypt — any underemployed adventurer could be found to do that. Perhaps he was a hedgehog after all.
Contemplating our own times, we know everything because it is a click of a mouse away. But few are the times when we are called upon to know things like Thomas Young did — by unerring attention to detail and the patience to return to elementary principles. This is a problem of our age, and most sadly it is particularly true of education. We stand on the shoulders of giants and take the view for granted; not many find time to meander down the byways of arcane knowledge. As this book reminds us, generalists in any field are odd creatures, but they should be cherished for originality of thought and not dismissed as gadflies.