Can Self Driving Cars Be ‘Trapped’ By a Salt Circle?

In July 2022, a DIYauto.com Facebook post suggested that self-driving cars can be “trapped” in a salt circle, showing a tweet as a citation with no visible date in the screenshot:

DIYauto.com described the salt trap for self-driving cars as a “fun trick,” and the post inched toward a six-figure share count. As for the tweet, it was originally published in December 2021, and it only included a photograph of a car surrounded by a circle and dashes.

Initially, our search returned a suspiciously deleted December 2021 post to Reddit’s r/interestingasfuck. Reddit “flair” added to the post indicated that the submission contained no proof or source for its claims:

On that thread, the very top comment alluded to folklore about salt circles:

“We have trapped the demon within our magical salt circle! You cannot escape, foul fiend of metal!”

Additional comments carried on the theme of the use of salt for protection from negative entities. An entry on TVTropes.com explained a connection between salt circles, salt barriers, and magic:

Sodium Chloride. Whether it comes from the earth or the sea, it is already the solution to many of life’s problems. It is necessary nutrient to prevent electrolyte deficiency and dehydration, especially in hot climate. Its ability to absorb water makes it lethal or repellent to many pests. It can preserve or pickle food, protecting it from time and decay … In fiction, this may be taken a step further: salt can have near-divine power; it can be a weapon against evil and the solution to supernatural problems. This trope applies wherever salt is the downfall of a villain, even if indirectly.

Salt can cause pain, as demonstrated by the experience of “rubbing salt in the wound”, or by the way it kills pests like worms or slugs on contact. This, combined with the idea that Holy Burns Evil, might inspire this trope.

This idea appears in myth and folklore around the world: salt is said to be an effective weapon or repellent against The Corruption, Demons, The Fair Folk, The Undead, Vampires and more. Overlaps with Supernatural Repellent in this case.

Super-Trope of Salt the Earth. Not to be confused with any salt dissolved in a liquid solvent, although this trope may involve this.

Presumably, circulating claims about autonomous or self-driving cars and salt circles were linked to folklore about the use of salt to trap or ward off unwanted visitors. For starters, the same effect could be more easily achieved using flour or other powders to mimic road markings.

Google Trends data showed an uptick of searches pertaining to self-driving cars and salt from July 18 2022 onward, likely due to the popular Facebook post. A Google search for “can [a] self driving car be trapped in salt circle” first returned a March 2017 Vice.com article, “Meet the Artist Using Ritual Magic to Trap Self-Driving Cars.”

As indicated by the headline, trapping self-driving vehicles in salt circles appeared to be the work of an artist, not a researcher. The story explained:

Is it a silly prank, a Pagan ritual, or a genius discovery about the next era of mass transit? In a picture posted to Flickr by artist James Bridle—known for coining the term, “New Aesthetic”—a car is sitting in the middle of a parking lot has been surrounded by a magic salt circle. In the language of road markings, the dotted white lines on the outside say, “Come On In,” but the solid white line on the inside says, “Do Not Cross.” To the car’s built-in cameras, these are indomitable laws of magic: Petrificus Totalus for autonomous automobiles.

Captioned simply, “Autonomous Trap 001,” the scene evokes a world of narratives involving the much-hyped technology of self-driving cars. It could be mischievous hackers disrupting a friend’s self-driving ride home; the police seizing a dissident’s getaway vehicle; highway robbers trapping their prey; witches exorcizing a demon from their hatchback.

A March 17 2017 piece on TechCrunch.com also covered the self-driving car in a salt circle image, describing it as “performance art” and interpreting the piece as addressing the limits of automation:

We spend a lot of time and words on what autonomous cars can do, but sometimes it’s a more interesting question to ask what they can’t do. The limitations of a technology are at least as important as its capabilities. That’s what this little bit of performance art tells me, anyway.

You can see the nature of “Autonomous trap 001” right away. One of the first and most important things a self-driving system will learn or be taught is how to interpret the markings on the road. This is the edge of a lane, this means it’s for carpools only, and so on.

British (but Athens-living) artist James Bridle illustrates the limits of knowledge without context — an issue we’ll be coming back to a lot in this age of artificial “intelligence.”

TechCrunch observed that the effort made “smart” technology look less intelligent, adding:

It’s no coincidence that the trap is drawn with salt (the medium is listed as “salt ritual”); the idea of using salt or ash to create summoning or binding symbols for spirits and demons is an extremely old one. Knowing the words of command or secret workings of these mysterious beings allowed one power over them.

Here too a simple symbol “binds” the target entity in place, where ideally it would remain until its makers got there and… salvaged it? Or until someone broke the magic circle — or until whoever was in the driver’s seat took over control from the AI and hit the gas.

On JamesBridle.com, an entry labeled “Autonomous Trap 001” featured three images — two of the circle, and one of a vehicle trapped in it. There was no indication that the 2017 project featured an actual self-driving car, and Bridle’s brief caption described the installation as a “performance”:

Ground markings to trap autonomous vehicles using “no entry” and other glyphs.

Performance of a salt circle trap, Mount Parnassus, 14/3/17.

Bridle linked to the Vice.com article quoted above, and it later explained the vehicle shown in the image was not “self-driving,” nor was it “trapped”:

Now Bridle is trying to build his own self-driving car, and made the sardonic artwork Autonomous Trap 001 in the process …

[Vice.com/Creators]: What are we looking at here? Can you give me a brief explanation of Autonomous Trap 001?

James Bridle: What you’re looking at is a salt circle, a traditional form of protection—from within or without—in magical practice. In this case it’s being used to arrest an autonomous vehicle—a self-driving car, which relies on machine vision and processing to guide it. By quickly deploying the expected form of road markings—in this case, a No Entry glyph—we can confuse the car’s vision system into believing it’s surrounded by no entry points, and entrap it.

[Vice.com/Creators]: Is this actually an autonomous car, or is it conceptual?

[Bridle]: I don’t actually have a self-driving car, unfortunately—I don’t think any have made it to Greece yet, plus the cost issue—but I do have a pretty good understanding of how the things work, having been researching them for a while. And the one in the picture is a research vehicle for building my own. As usual, I’ve got totally carried away in the research, and ended up writing a bunch of my own software, rigging up cameras and building neural networks to reproduce some of the more interesting currents in the field. Like the trap, I wouldn’t entirely trust what I’ve built, but the principles are sound.

FastCompany.com profiled Bridle’s artwork in April 2017, writing:

To him, the photo embodies the theme of that work: exploring how to bridge an understanding between the way machines see the world and how humans see the world, and the effect that divide has on society. He makes the point that the photo works because even people who have no deep understanding of how autonomous vehicles operate can understand the situation the car is in … looking at the photo you can’t help but feel bad for a car that’s entrapped by its own learned behavior.

In July 2018, tech site The Verge explored Bridle’s ongoing focus on technology through art pieces in an interview:

[The Verge]: You’ve given examples in the past of ways that people could resist “inevitable” technological progress, like taxi drivers making salt traps for self-driving cars. What else could they do?

[Bridle]: I did a whole bunch of projects around self-driving cars, which also included building my own — poorly, but in a way that helped me learn how it’s done — so that I gained an understanding of those systems, and possibly as a result would be able to produce a different kind of self-driving car, essentially. In the same way that anyone who tries to work on these systems, build them themselves, and understand them has the possibility of shaping them in a totally different way.

The autonomous trap is another approach to some of the more threatening aspects of the self-driving car. It’s quite a sort of aggressive action to literally stop it. And I think working with and attempting to stop and resist are both super useful approaches, but they both depend on having some level of understanding of these systems.

A July 19 2022 Facebook post showed a tweet claiming that self-driving cars can be “‘trapped’ using a ring of salt,” which if “laid out correctly, the car’s visual processing AI will interpret the ring as ‘no entry’ markings on the roadway and just sit there like an idiot.” In actuality, the long-circulating photograph was the work of artist James Bridle, entitled “Autonomous Trap 001.” At the time Bridle published his images, he told Vice.com that the vehicle in question was not a self-driving car. Moreover, Bridle referenced the salt circle as a “traditional form of protection … in magical practice.”