If behind popular fascination with Freudian theory there was a nervous, often guilty preoccupation with the self as sexual, behind increasing interest in computational interpretations of mind is an equally nervous preoccupation with the self as machine.

Because you can text while doing something else, texting does not seem to take time but to give you time. This is more than welcome; it is magical.

What is so seductive about texting, about keeping that phone on, about that little red light on the BlackBerry, is you want to know who wants you.

The computer is a mind machine. It doesn't have its own psychology, but in a way it presents itself as though it does.

We're lonely, but we're afraid of intimacy. And so from social networks to sociable robots, we're designing technologies that will give us the illusion of companionship without the demands of friendship.

There are moments of opportunity for families; moments they need to put technology away. These include: no phones or texting during meals. No phones or texting when parents pick up children at school - a child is looking to make eye contact with a parent!

The kind of solitude that refreshes and restores is very important, not just for children, not just for adolescents, but for all of us. If you don't teach your children how to be alone they will only be able to be lonely.