When Thomas Browne, physician and natural philosopher, went hunting in the 1650s in books, on beaches, and in hedgerows for quincunxes in nature and culture, he discovered them in the structure of pine cones, the battle formations of the Greeks, the angles of incidence of light upon the retina, and the planting patterns of orchards. It turns out the quincunx (imagine the corners of a diamond with a dot in the middle) is everywhere. Three and a half centuries later, on a psychogeographic Brownean pilgrimage between Bury and Norwich, Hugh Aldersey-Williams found in those same hedgerows quincuncial hubcaps, which in turn prompted a meditation on that most modern of molecules, the pentagonal buckminsterfullerene. Browne’s apparently eccentric observational exercise amounts to a rule in nature, one he was able to identify with an indifferent set of magnifying lenses, the naked eye, and shanks’s pony. The instruments were primitive, but his slender quincuncial essay The Garden of Cyrus (1658) (its first known reader called it ‘no ordinary book’) epitomises the imagination of this most intellectually open and adventurous of Renaissance polymaths.

Browne’s much more influential book was a massive encyclopaedia of human misunderstanding, a register of vulgar errors that catalogues epidemical false thinking as well as the extent of his remarkable curiosity. The chiefest of pseudodoxies is a belief in whatever is generally believed: for us, that’s quack diets, alien abduction, demonic possession, conspiracy theories of all kinds; for him, it’s nonsense from folk wisdom, Aristotle, and the Fathers of the Church. Is it true that ‘Crystal is nothing else but Ice strongly congealed’? Obviously not, he answers – the meanest understanding shows that it doesn’t melt in hot weather and doesn’t float in water, despite the assertions of Pliny, Ezekiel, Augustine, and Gregory the Great. Do chameleons really live on air alone? Why would the creature have teeth and a digestive tract when ‘the providence of nature … disposeth of no part in vain’? ‘That the Jews stink naturally is a received opinion we know not how to admit,’ he concludes. Browne, unlike most of his compatriots, had met Jews in medical school on the Continent decades before they were readmitted to England by Cromwell; personal experience and logic told him it is impossible to fix such ‘national’ characteristics on any group, least of all one without a fixed address. Wandering the thickets of his learned allusions, gorgeously labyrinthine prose, and the breathtaking glitter of his phrasing, we are taken, case by case, back to first principles in common sense and experience: we are taught by Browne how to think.

Aldersey-Williams’s engaging and thoughtful book is an essay on Browne’s prescience as naturalist, entropist, biodiversifier, bad-science caviller, cultural historian, curioso, and tolerant humanist. He believes that Browne’s scientific and ethical concerns, apparently recondite and confined to an estranged, pre-Enlightenment past, in fact predict our own. Through a Brownean lens he looks at modern ‘vulgar’ errors, such as the MMR vaccine scare and homeopathy; we are taken to a Norfolk field where some recovered burial urns became the subject of a scholarly tract (there is no sign of other remains); and to the former site of Lower Shibden Hall, near Halifax, where Browne wrote his first, celebrated work, Religio Medici (1642). It is now an abandoned artificial ski slope. There can hardly be a more acutely Brownean image of futility and evanescence.

Aldersey-Williams is most attracted to Browne the scientist and medic, one whose inclination was to look about him in nature as well as in printed authorities. His most extended attention is given to very Brownean digressions on the statistical probability of dying on one’s birthday (which Browne may or may not have done, since he didn’t seem altogether sure of his own), on the possible medicinal use of potable gold, a delusion first promoted by alchemists that continues to this day, and on other modern obsessions. In today’s alternative medicine and the madness of crowds he finds modish pseudodoxies hardening into concreted truths. Is this the unconscious mimicry of literary homage, or is his research running away with him, as it did with Browne? Browne’s fertile neologising, also documented here, was essential in a period when discovery was outstripping the capacity of language to express it; he is one of the greatest contributors to the English lexicon (‘medical’, ‘antediluvian’, ‘electricity’ and ‘hallucinate’ are all his, and hundreds more). What would he have made of the hideously vulgar error that recently prompted the outraged neighbours of a paediatric consultant to mistake him for a paedophile?

Like some of the most compelling biographers, Aldersey-Williams partly inhabits his subject. The book opens with a re-creation on bicycle of Browne’s journey from a notorious witch trial in Bury, where he was the expert witness, back to his home in Norwich. Later, author and subject conduct an extensive conversation when the tercentenary statue of Browne on Hay Hill in Norwich descends from its plinth for a stroll around the city. A slightly impatient Browne says, ‘Phew. You would not believe the piaculous things I have seen from up there. The vulgar people of Norwich do not much change.’ (Piaculous, another of Browne’s words, means wicked.) ‘I feel you have lessons for our century,’ says Hugh. ‘So, is this some kind of bromance?’ Browne responds, doubtless having picked up the argot of the 21st-century skateboarders in the market square. The discussion moves on to the subject of miracles: Browne believed in them but wished not to witness one since it is easy to credit what one has seen; harder, and an act of faith, to believe without ocular proof. Arguing against assertion by faith, Aldersey-Williams offers to pop into the local bookshop to pick up copies of The Origin of Species and The God Delusion. ‘Who is this saltimbanco?’ Browne asks (of Dawkins, not Darwin) – because for Browne God is a delusion, a metaphor, though not of the Dawkinsian variety. He believes in the literal truth of biblical fact, including the deity himself; but he thinks we’re just not clever enough to understand what that truth means.

Like our bones and ashes and the urns and graves that contain them – the subject of Urne-Buriall (1658), Browne’s most radiant work – much of his material remains have vanished. His records, effects, houses, and books are lost, or mingled anonymously with the vast pile of historical detritus we possess and curate. He was not, other than in his published works, self-preserving, having probably destroyed most of his letters, as well as his manuscript drafts of every major work. The man who could not reliably state his date of birth also neglected to write his name in a single book we know him to have owned. This teasing absence compels Aldersey-Williams to assemble something less like a biography, more like a mental inhabitation, a state of mind that he finds characteristic of Browne’s own day, but also of ours. Although he never deploys that hideous word ‘relevance’, and this is not, thank goodness, How Browne Can Change Your Life (although Browne probably can), occasionally one senses an over-keen wish to discover a too-familiar Thomas Browne – one who, with his genial even-mindedness, might slip with relative ease into secular, spiritually riven, scientific modernity and engage in its debates with tolerant asperity. Browne’s ‘decorous’ 17th-century handwriting is reproduced to make a graceful point about his orderly spirit and his continuing intelligibility to us, his ‘after-preservers’. But that hand is, alas, a copyist’s, not Browne’s, whose scrawl confounds scholars and confirms the traditional illegibility of medical prescriptions. Browne is in fact profoundly strange, marginally legible at times, not only in his penmanship but also in his thinking and his beliefs.