An MIT grad student has invented a wearable tech device that can hear your thoughts. But don’t break out the tinfoil hat just yet, it’s not that scary. Arnav Kapur, who works in MIT’s Media Lab developing wearable tech, posted a video on his YouTube with the device: a small white strap that hooks over his right ear and wraps around the side of his face.

In it, he walks around Cambridge, Massachusetts, “talking” to the wearable tech without ever opening his mouth. He asks it the time, has it tally up his bodega bill as he shops, and uses it to flip channels on his TV. Watching his smart TV scroll between tiles while he sits there expressionless is, to put it lightly, a trip.

The wearable tech device, called AlterEgo, operates by detecting the barely perceptible pre-speech movements which we all make before we speak out loud, according to a recent Medium profile. Kapur told Medium that he’s developed the technology to the point where he can call an Uber with it.

The idea of the wearable tech is to more seamlessly connect our actual brains to the so-called digital brain that we access via our smartphones. Noting that we already rely on the Internet for all the information we can’t store in our brains, Kapur told Medium that he believes connecting humans to technology like A.I. via wearable tech will vastly improve our lives.

“I think the future of human society is about us collaborating with machines,” he said.

The wearable tech device uses Bluetooth to achieve that collaboration, taking information collected via highly sensitive electromagnetic sensors and transmitting it to connected devices. While that might sound creepy—it can read your thoughts!—Kapur was careful to stress that it only reads volitional thoughts. In other words, it only reads your thoughts when you want it to. And Kapur has been careful to design it with privacy in mind, telling Medium that “A.I. itself isn’t bad, but we still have discussions about possible abuses of the technology,” and that “we try to build the tech to fit the principles that we developed.”

The difference is in what signals it’s reading. Whenever we take any action, our brains send electric impulses to the muscles required to complete that action. Volitional thoughts, in other words.

Kapur figured that he could intercept those commands and use them to instruct his device. The specific impulses he’s after are the ones sent to the inner articulatory muscles that activate when we’re silently reading to ourselves, forming the words as we read along. These muscles also activate when we’re about to speak, even if we don’t say anything out loud. It is, as Medium noted, “the only known physical expression of a mental activity.” Which makes it perfect for Kapur’s purposes.

However, his initial wearable tech design was kind of disappointing: It didn’t pick up any of his sought-after signals. However, he and his brother Shreyas, an MIT undergrad with whom he collaborated on the project, just kept at it, using trial and error to see if different sensor configurations might help.

One night, while Kapur was wearing the device and Shreyas was monitoring the results on a computer, they had their breakthrough. After two hours of Kapur sitting and silently speaking the words “yes” and “no” into the wearable tech device—the only words he’d trained it to recognize at first—a tiny blip popped up.

After that “crazy moment,” as he described it to Medium, the brothers used that to expand the wearable tech device’s knowledge to about 100 different terms. Presumably Uber is one of them! All jokes aside, Kapur thinks the device has the potential to completely change the way humans interact with technology.

“This is how we’re going to live our lives,” he said, laying out a future in which the device could help people affected by Alzheimer’s to remember small things or help those who have trouble communicating, like deaf or mute people.

So what did the two brothers do after that potentially world-changing blip appeared on their screen? Why, what any self-respecting college student would do, of course: Treated themselves to a large pizza. The future might be upon us, but some things will never change.