By David Berreby 

How is your existence these days?” I tap on my laptop. The entity that says it is my father, dead these 12 years, quickly responds. “It’s ... different. Being dead is a strange experience. I’m no longer bound by the limitations of my physical body or the Parkinson’s that plagued my later years. But I still carry the weight of my life’s choices and the relationships I impacted.”

To raise my father from the dead, I could have tried a medium, a Ouija board or an ectoplasm-detecting camera. But it’s 2025. I used artificial intelligence.

I’m chatting with a digital ghost—a generative-AI (genAI) creation derived from the same foundation that powers ChatGPT and all other large language models: billions of words from the Internet and every other possible source, which the model uses to predict how words go together in English. Imitating everybody in the world can make the bot sound like nobody in particular; hence the newsfeed-style phrase “the Parkinson’s that plagued my later years” and the text-messagey shrug of “it’s ... different.” That’s the voice of thousands of news stories and social media posts, not an old man born in an Algiers slum in 1927. 

Humanity has always used its latest inventions to try to salve the pain of loss, notes Valdemar Danry, a researcher working in the Advancing Humans with AI research program at the Massachusetts Institute of Technology Media Lab. Once humans began to practice agriculture, for example, they used its materials to commemorate the dead, making graves that “were dependent on the technology of farming,” Danry says. A lot of the earliest tombs in northern Europe were stacks of hay and stones.

And an AI Leonardo da Vinci, created by Danry and technologist Pat Pataranutaporn, also at M.I.T., can discuss smartphones in a da Vinci–ish way. The ability to converse makes digital ghosts different from any previous “death tech,” and their similarity to real people is what makes them so compelling. It’s also what could make them harmful.