Of all of the wonders witnessed by Sir John Mandeville, a 14th-century English knight, none was extra astonishing than the “wondirfulle” fruit of a tree he encountered on his travels in India. This fruit resembled a gourd, however minimize it open and you’ll discover tiny flesh-and-blood lambs. One other medieval traveller, the Italian Friar Odoric, had additionally journeyed extensively via Asia and had learnt about the identical fruits from “individuals worthy of credit score”.
Different accounts urged that when the fruit ripened, the outcome was a full-fledged lamb, or one thing very prefer it, connected to the stem of the plant by an umbilical wire. The lamb would graze close to its roots, however when all of the grass inside attain had been consumed, the Vegetable Lamb would die.
Readers with a stable grasp of botany could already remember that there isn’t any such factor as a Vegetable Lamb. Certainly, there was possible no such individual as Sir John Mandeville — his celebrated travelogue was written by individuals unknown, and based mostly closely on earlier works, together with that of Odoric.
But this didn’t cease tales concerning the Vegetable Lamb from circulating, and being believed, among the many cognoscenti of Europe for hundreds of years. Baron von Herberstein, an envoy to Russia practically two centuries after the Mandeville travelogue turned well-liked, confessed to being sceptical earlier than changing into a believer after many “individuals of credence” instructed him they’d seen and tasted the scrumptious plant-animal hybrid.
“It took practically 4 centuries after Mandeville’s writings appeared for European botanists and biologists to recognise the Vegetable Lamb as a fable,” write Cailin O’Connor and James Owen Weatherall in The Misinformation Age (2019).
Does that sluggishness replicate the failure of a very medieval mindset, or does it have classes to show us as we speak?
Think about some barely newer instances. James Lind, a Royal Navy surgeon, is widely known as we speak for locating that citrus fruit cured scurvy, after working a primitive scientific trial in 1747. The one hassle is that he did no such factor.
Lind performed a trial all proper, nevertheless it made subsequent to no distinction to anybody’s notion of citrus fruits. Each earlier than and after Lind’s trial, they have been thought by some sailors to be useful, however Lind’s work made little impression. His Treatise of the Scurvy (1753) is a mass of confusion, though the transient description of the trial practically 200 pages in is obvious sufficient. Lind ended up recommending a boiled citrus syrup, and this proposal was extensively ignored — which is not any nice disgrace, since boiling lemon juice destroys vitamin C and thereby renders it ineffective as a treatment for scurvy.
Citrus fruit was embraced by the Royal Navy half a century later, and never due to a scientific trial however as a result of it was advisable by a high-status physician, Sir Gilbert Blane. Nonetheless later, the “limeys” misplaced confidence within the treatment. Stale, badly saved lime juice accommodates virtually no vitamin C however, within the age of steam, odd sailors not often obtained scurvy anyway as a result of voyages have been fast and common refuelling stops have been required. Polar expeditions have been one other matter, and within the late 1800s have been ceaselessly struck by scurvy regardless of using (stale) lime juice.
On the similar time, germ principle was rising and the concept that scurvy was one thing to do with citrus fruit started to appear quaint. Because of this, Robert Falcon Scott was suggested by medical consultants that scurvy was brought on by toxins known as ptomaines, and his Antarctic expeditions have been troubled by scurvy greater than 150 years after Lind’s “discovery”. Ptomaine poisoning is not any extra an actual clarification for scurvy than the Vegetable Lamb is an actual animal.
Ninety-nine years in the past, the Korean newspaper Jungoe Ilbo printed a narrative titled “Unusual Hurt from Electrical Followers”, warning that having a fan working too near you would possibly trigger demise as you choked by yourself carbon dioxide. (It gained’t.) For many years, Korean newspapers continued to run articles about individuals dying within the presence of followers, whether or not or not there was any motive to consider the fan was in charge.
Why will we consider issues that aren’t true? Two modern views are that we consider falsehoods due to political polarisation, or that we consider them due to emotional triggers akin to concern, lust or greed. That explains why the political social gathering trustworthy are keen to consider virtually any smear concerning the hated enemy, whereas closing their eyes to wrongdoing on their very own aspect — and why individuals will ship cash to strangers on the web claiming to be Nigerian princes.
However neither tribalism nor greed explains the beliefs that your desk fan might kill you, that citrus fruit doesn’t forestall scurvy and that someplace in Asia lambs develop on bushes. Nor do they clarify why these false beliefs continued for therefore lengthy.
For O’Connor and Weatherall, the purpose of the Vegetable Lamb story is that almost all of what we consider, we consider as a result of everybody round us believes the identical factor. From the assumption that recent greens are good so that you can the concept that the Earth is principally spherical, our worldview displays the worldview of the society wherein we stay.
The world is usually a complicated place. Seeing white fluff bursting from cotton crops for the primary time, it’s not shocking that Europeans perceived a resemblance to lamb’s wool. Sailors on fast-moving steamships derived no antiscorbutic profit from stale lime juice — and wanted none.
When actuality provides us with alerts which can be mystifying (white fluff on a plant) or inconsistent (with or with out lime juice, scurvy could or could not develop) or long-delayed (cigarettes dramatically increase your threat of lung most cancers) it’s hardly a shock that we flip to one another for info.
Or we could flip to the consultants, who will generally have a clearer view of what’s going on. (Not at all times: Scott’s advisers have been fretting about ptomaine poisoning.) But we nonetheless must resolve who we should always regard as having related experience. That may be a scientist, or a YouTube influencer, or Wikipedia, or the output of a big language mannequin — however in any case we are going to take cues from others as to who counts as “individuals worthy of credit score” and who doesn’t.
“Most of us get our false beliefs from the identical locations we get our true ones,” write O’Connor and Weatherall. It’s a sobering thought.
I draw three classes. First, if most of our beliefs are handed to us by the society wherein we stay, it’s vital that our society itself values reality and truth-telling. Second, it’s by no means a nasty concept to cease and assume for a second about what different individuals inform you.
And third, contact with unfamiliar views is wholesome. What finally punctured the Vegetable Lamb fable was that each time Europeans journeyed to Asia searching for the creature, the locals discovered the entire enterprise hilarious.
Written for and first printed within the Monetary Occasions on 19 Aug 2026.
I’m working the Oxford Half Marathon in October in assist of an excellent trigger and in reminiscence of my mom. When you felt in a position to contribute one thing, I’d be extraordinarily grateful.
