It's generally considered a good idea to know where you are at all times, apart from occasional lapses1（失效，流逝） due to alcohol or passion. Technology is now making it increasingly easy for everyone else to know where you are as well. We are so used to having mobile phones around us that we no longer see how much emotional reassurance2 they provide. We have slowly shifted from feeling slightly unnatural3 when connected ("Hello? Who's on the line? Hello?") to feeling very unnatural when disconnected ("And then I lost my mobile. Nightmare"). This week I sat next to a woman on a train whose bag kept vibrating with an irritating（刺激的）, mosquito-like hum. I wondered if she had hearing problems, and hadn't noticed that her phone was going off, or was missing a vibrating alert because the phone was in an outside pocket of her bag, nicely positioned to irradiate（照耀） my head. I asked if she knew if her phone was ringing. "Oh no," she said complacently4. "That's my Blackberry collecting my e-mails."It may be that she didn't know she could set her device not to give her a vibromassage（振动按摩） at three-second intervals5, but I suspect she just liked the reassurance provided by this humming (苏州故事会)network node in her Mulberry. It was impossible to miss the warm glow she got from being connected. We don't all have Blackberrys but we pretty much all have phones, and we are all getting the same nice warm glow of connection and validation6 from these devices.Personal productivity guru David Allen, godfather of Geeing7 Things Done, an approach to managing your day which has become something of a cult8 amongst programmers and tech industry workers, sees the Blackberry as symptomatic not of our efficiency but of our failure to make decisions and priorities. We can't make decisions about what's important, so we carry our office around with us at all times, compensating9 for our failing powers of decision. (He even speculates that after a while people will start carrying even larger handhelds, called Watermelons, to provide even more information, reassurance, and security.)Many people in the rich parts of the world live atomised urban lives characterised by anonymity10, hurry, and rush, and a kind of low-level anxiety caused by the stresses of the world we've built ourselves. We seem to be turning to digital devices to provide compensatory connections that remind us who we are and that give us good feelings of connection and identity.Mobile phone companies know this and market their products to young preteens. I've seen research which explains that the period of adolescent uncertainty11, in which you're not really sure who your friends are, is the time when a mobile phone for texting and calling friends is at its most powerful. The modern mobile phone user in the UK will spend most of their money on calls before the age of forty. After that, presumably, they have a landline and a fixed12 circle of friends, and don't need constant texts and calls to reassure13 them that they're accepted by their peer group.I actually don't think any of this is inherent in the technology. You can do exactly the same thing with a landline. If you remember Woody Allen's brilliant film, Play It Again Sam, the hero's friend Dick, an overworked businessman, neurotically14 provides phone numbers to his colleagues wherever he goes so that he can be in touch with the office at all times.Dick: I'll be at 362—9296 for a while; then I'1f be at 648—0024 for about fifteen minutes; then I'II be at 752—0420; and then I'll be home. At 621—4598. Yeah, right George, bye-bye.Linda: There's a phone booth on the corner You want me to run downstairs and get the number? You'll be passing it.Dick is a self-important corporate15 jackass who misses what is going on around him because he's always in pursuit of an important business deal. When did we all turn into him?