In T. H. White’s series of novels The Once and Future King, the wizard Merlyn turns the young Arthur, future king of England, into a variety of animals. As a small fish, Arthur swims in a moat and is terrorised by a stronger pike; as a hawk, Arthur learns to respect the dominant old falcon. In giving him these experiences, Merlyn aims to educate Arthur and make him a good king.
By the 2040s, it had become possible, to a limited extent, to achieve with science what Merlyn managed with magic: to give humans the direct experience of being another species (although not without controversy).
The method, of course, was via neuroscience. Our understanding of the brain progressed rapidly in the 21st century, and highly detailed maps of brain networks became available for a range of animals. In 2024, the first wiring diagram of all the neurons in was produced, and in 2025 a highly detailed map of a mouse brain was created.
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Alongside this mapping, the recording and stimulating of neurons became accurate and repeatable. We started to understand what different regions of the mammalian brain did, as well as how to control them. In 2015, scientists wove together the input and output signals of the brains of four rats. Each rat had electrodes implanted in regions of the brain involved in movement. By sending electrical signals to the rats, the team could join together the rodents’ brains.
Methods to monitor, stimulate and engineer brains progressed. In 2035, a scientist in Seattle decided to attempt to network his own brain with that of a lab rat. Wireless electrodes were used on the man’s scalp, while the rat, with a smaller brain, underwent invasive implantation. The optical region of the brain was selected for testing, as this was well understood and was relatively simple. A computer acted as intermediary between the human and the rodent, smoothing the signals passing in both directions. When connected, the man closed his eyes and saw through those of the rat.
In some ways, the experience was a bit of a letdown. Rats have poor vision, with only two types of cone cell in their eyes, compared with our three, so the scientist perceived a more limited palette than he was used to. Yet he was the first human in history to experience the world as another species.
In 2035, a scientist networked his own brain with that of a rat. In some ways, the experience was a bit of a letdown
Refinements soon allowed improvements as more brain regions became accessible. A human mind-melded to a rat could move with the rodent, and smell and feel what it sensed. Where there were things that the human brain hadn’t evolved to interpret, such as input from the rat’s whiskers or the presence of ultrasound, artificial intelligence adapted the signals to make them available to humans.
One immediate consequence was around ethical considerations for animals. After experiencing the world as a rat, researchers stopped keeping them in cages and gave them larger, more complex areas to live in.
Should the brains of animals be exploited in this way? Scientists argued that mind-melds were simply the modern equivalent of using domestic animals. When we ride a horse, for example, we are controlling it with a bridle and stirrups, which are removed at the end of the ride. Researchers who entered the brains of horses to “be” them as they galloped said this was a similar action, and when the electrodes were removed, the horses’ brains returned to a singular, independent state.
The zebra finch – the bird about which most was known from a neurobiological point of view – was another organism to get the mind-meld treatment. The great appeal of being a bird, of course, was flight. When electrode technology had been miniaturised enough to fit a bird and still allow it to fly, humans connected to the animal could, it was hoped, experience the thrill of cheating gravity.
However, the avian brain is very different to the mammalian brain, lacking the cerebral cortex, and mind-melding was glitchy and less successful here. But people still desperately wanted to fly, so pipistrelle bats were selected.
When humans mind-melded with bats, enacting Bram Stoker’s imagined transformation of Count Dracula into bat form, one wit remembered an old argument over the “hard problem of consciousness”: Thomas Nagel’s 1974 essay, “What is it like to be a bat?”. Even if we could fly, Nagel argued, even if we could squeak in ultrasound and catch moths with sonar, we would never know what being a bat feels like. Well, in the early 2040s, we did.
The mind-meld technology was phased out not long afterwards, however, as people decided it was unethical to forcibly take control of the brain of another animal. Perhaps then, like Merlyn with Arthur, there had been some educational value in the project.
Rowan Hooper is 91av‘s podcast editor and the author of How to Spend a Trillion Dollars: The 10 global problems we can actually fix. Follow him on Bluesky @rowhoop.bsky.social
