He thinks that most people with cell phones say that they use them for important and relevant things to communicate things with great value.

But that in practice they are a bunch of excibitionists who love to tell all the people what they are doing.

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Sources:

Umberto Eco, Not a Cellphone Exhibitionist. The New York Times. (November 6, 2007). https://archive.nytimes.com/artsbeat.blogs.nytimes.com/2007/11/06/umberto-eco-not-a-cell-phone-exhibitionist/
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