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In 2008, Tiffany Shlain’s father, Leonard, was diagnosed with brain cancer, and she began to change her use of technology when the two of them were together. “Some days he would have only one good hour,” she later wrote in the Harvard Business Review, “and I didn’t want to be distracted when I was with him, so I’d turn off my cellphone.”

Eventually, Shlain, a filmmaker, extended the idea into a full day without screen use. She called it a tech shabbat — after the Jewish day of rest — and she has written several articles and a recent book, called “24/6,” about the idea.

“The digital revolution has blurred the lines between time on and time off, and time off is disappearing,” she wrote in The Boston Globe. “As for our leisure time, we’ve created a culture in which we’re still ‘working’ while we play: needing to photograph every moment, then crafting witty posts of our ‘fun, relaxing activities’ on Instagram, then obsessively checking responses. We can barely catch our breath in the tsunami of personal and work digital input, which results in us not being truly present for any of it.”