Any fan of the Harry Potter series will know that J.K. Rowling draws inspiration from a myriad of myths, legends and historical events to create her wizarding world. But despite Harry Potter being a magical universe where logic need not apply, some elements are closer to science fiction than true magic. Many of Rowling’s ideas have parallels in Muggle medicine: one can’t help but notice the similarity between the Obliviate charm and certain forms of amnesia, or search for scientific explanations for Voldemort’s serpentine appearance. Exploring these links further reveals that both horrific diseases and incredible advances can seem just like magic.

Rowling did not invent Nicolas Flamel and the philosopher’s stone, so where does the true story of alchemy intersect with her wizarding world?

The search for the legendary philosopher’s stone, at least in Europe, began with Ancient Greek alchemists, who believed all matter was composed of four essential elements: air, fire, earth and water. Gold could surely be created from other substances provided they could discover the necessary ratios of these elements. The philosopher’s stone was believed to be a substance that could not only transmute low-grade metals into silver or gold but would also heal and grant immortality to the user. Medieval alchemists experimented with thousands of combinations of materials to find the stone, laying the foundations for modern chemistry and pharmacology.

Nicolas Flamel, a 14th-century French bookseller and philanthropist, is only connected to this practice through legends arising in the 1600s. The real Flamel died in 1418 and was buried in Paris (beneath a tombstone he designed himself—rather a morbid activity for someone rumoured to be immortal). The last popular figures to seriously pursue alchemy were probably Robert Boyle and Isaac Newton, before they and their contemporaries replaced alchemy with modern chemistry and physics.

From keeping Muggles oblivious, to exploring Voldemort’s past through the Pensieve, memory spells safeguard the wizarding world. But can neuroscience replicate this memorable magic?

A decade before the Black Mirror episode about an implant that stores and replays memories, Rowling invented the Pensieve: a basin that stores and replays memories. But memory is far more fluid than the movie-like recollections often depicted in TV and literature. When we remember something, we reconstruct the event from small pieces of information scattered all over the brain. This process incorporates details from the present, transforming the memory into a caricature of its original self—like how Slughorn alters his memory to conceal his role in Riddle’s rise to power. For example, when 3,000 people were asked to recall where they were during 9/11, less than 63 per cent had accurate recall a year later, yet on average they rated themselves ‘four out of five’ on how confident they were in their recollection. More disturbingly, psychologists can implant entirely false memories with relative ease, using leading questions or repeatedly describing an event to someone until they become convinced they were present. Memory is malleable and dispersed throughout the brain—not a discrete entity that can be preserved in a Pensieve.

Though we alter our memories without realising, is it possible to remove them entirely? The usefulness of a real-life Obliviate is clear to anyone who has dealt with post-traumatic stress disorder. A psychological technique called exposure therapy utilises the malleability of memory by having patients confront their trauma in a safe and calm setting, teaching the brain that there is nothing to fear. But this treatment is not perfect, and some researchers have instead sought a pharmacological approach. By giving a heart medication called propranolol during exposure therapy, we can reduce the physiological symptoms of anxiety and help the brain reclassify the memory as non-threatening.

Memory manipulation also raises ethical questions. The power to induce or prevent a criminal confession, to alter someone’s identity, or to make them question their perception of reality is dangerous. Especially if, like Muggles who have witnessed magic, this occurs without our consent.

The Dark Lord’s signature look is an unforgettable part of the Harry Potter series, but it took considerable effort to recreate for the films. The visual effects team edited every frame individually to replace actor Ralph Fiennes’ nose with snakelike slits—that’s a lot of time and money spent on nostrils.

So how did Voldemort go from a hot 17-year-old student in Chamber of Secrets to a terrifying villain? The canon explanation, put forth by Dumbledore in Half-Blood Prince, is that his body became “less human” the more “his soul was mutilated beyond the realms of what we might call usual evil”. However, fans have offered more entertaining theories: frostbite from the snowballs Fred and George Weasley pelted at Quirrel’s turban, a botched nose job in Knockturn Alley, or overenthusiastic snogging with a Dementor. I propose two reasons for his missing nose that affect Muggles and wizards alike: cocaine and syphilis.

An unintended side effect of snorting cocaine is the constriction of blood vessels in your nose. This makes it an unorthodox substitute for Sudafed during a cold but can be dangerous if the blood supply is cut off for too long. Eventually, the cartilage in your septum dies and the bridge of your nose collapses, giving it a ‘saddle’ appearance—much like Voldy’s nose. You’d think that wizards would have magical means of getting high, but maybe the ‘potions’ of Wall Street are just as effective.

Lord No-noselemort may also have had syphilis. In the late stages of the disease, soft inflammatory growths called ‘gumma’ form to contain the infection. This destroys bone and cartilage, leading to the same saddle-nose deformity seen in cocaine abuse. Syphilis can also affect your pupils, perhaps giving the Dark Lord’s their slits. Most famously, syphilis can infect the brain, causing personality changes, like asocial behaviour and irritability. No wonder so many psychopathic villains were suspected of suffering from the disease, including Adolf Hitler, Al Capone and Idi Amin. Tom Riddle may have almost succeeded in protecting his soul, but it looks like he didn’t use other protection where it was warranted.

A vanishing nose, malleable memory and a stone that led to the discovery of thousands of chemicals: these real-life examples of medical discoveries or advances all sound magical. Us Muggles have a weapon more powerful than magic: the scientific method. The search for the philosopher’s stone may not have unlocked the secrets of immortality, but it led to the development of modern chemistry, which has produced substances more valuable than gold, and pharmacology, which has saved countless lives. Advances in neuroscience have revealed that, unlike those depicted by Rowling, memories are neither discrete nor fixed. And a few wild nights in Hogsmeade can change your appearance as much as splitting your soul. Mere Muggles have achieved far more than Rowling’s wizards (apart from perhaps Arthur Weasley) give them credit for. Who needs magic anyway?