Tony Fadell’s wife likes to remind him when their three children’s eyes are glued to their screens that it’s at least partly his fault.

Hard to argue. Fadell, who founded the smart thermostat company Nest in 2010 and who was instrumental in the creation of both the iPod and later the iPhone as a senior vice president at Apple, has done more to shape digital technology than many of his peers. But in a recent conversation at the Design Museum in London, Fadell spoke with a mix of pride and regret about his role in mobile technology’s rise to omnipresence.

“I wake up in cold sweats every so often thinking, what did we bring to the world?” he says. “Did we really bring a nuclear bomb with information that can–like we see with fake news–blow up people’s brains and reprogram them? Or did we bring light to people who never had information, who can now be empowered?”

Fadell was speaking as part of the Design Museum’s program around its current blockbuster exhibition, California, which examines the history and culture of digital technology in the Golden State, from early iPhone prototypes to the utopian festival and tech industry networking staple Burning Man to drawings of Apple Park. The conversation, called “Selling Freedom,” brought together Fadell; Bethany Koby, the cofounder and CEO of toy company Technology Will Save Us; David Edgerton, a historian of science and technology at King’s College London; and Judy Wajcman, a sociologist at the London School of Economics who studies the social impact of technology. They were charged with examining the consequences of having so much revolutionary technology coming from a single place.

The world Fadell describes is one in which screens are everywhere, distracting us and interrupting what’s important, while promoting a culture of self-aggrandizement. The problem? He says that addiction has been designed into our devices–and it’s harming the newest generation.

“And I know when I take [technology] away from my kids what happens,” Fadell says. “They literally feel like you’re tearing a piece of their person away from them—they get emotional about it, very emotional. They go through withdrawal for two to three days.”

At its root, this is a design problem. Fadell believes that products like the iPhone, as much as they are communication devices, are more attuned to the needs of the individual rather than what’s best for the family and the larger community.