Teenagers talk about the idea of having each other's 'full attention.' They grew up in a culture of distraction. They remember their parents were on cell phones when they were pushed on swings as toddlers. Now, their parents text at the dinner table and don't look up from their BlackBerry when they come for end-of-school day pickup.

I love sharing photographs and websites, I'm for all of these things. I'm for Facebook. But to say that this is sociability? We begin to define things in terms of what technology enables and technology allows.

There's a lot of research that indicates the brain rewards us for multi-tasking by giving us a shot of neurochemicals whenever we start a new task. Our brain rewards us even as our performance in every task degrades. We don't even notice that our performance is bad. We don't care. We feel like masters of the universe because our brain is chemically rewarding us for multi-tasking.

Everyone is always having their attention divided between the world of the people [they're] with and this other reality.

These days, when people are alone, or feel a moment of boredom, they tend to reach for a device. In a movie theater, at a stop sign, at the checkout line at a supermarket and, yes, at a memorial service, reaching for a device becomes so natural that we start to forget that there is a reason, a good reason, to sit still with our thoughts: It does honor to what we are thinking about. It does honor to ourselves.

What is the value of interactions that contain no understanding of us and that contribute nothing to a shared store of human meaning?

Technology doesn't just do things for us. It does things to us, changing not just what we do but who we are.