Few inventions of the 21st century have changed our lives as dramatically as the mobile phone, which marked its 40th anniversary this week. Today it is hard to imagine a world before it.
It was on April 3, 1973, when Martin Cooper of Motorola, made the first call - as he crossed a street in New York - on the company's DynaTac phone, later known as "the brick" because of its size and weight.
The technology behind that first call not only freed us from fixed phone lines, but opened the door to true mobility. All of us are aware of how mobile phones have changed our lives, and the changes are still coming.
Unfortunately, as we make technical progress we fail to cultivate our wisdom in equal measure. Smartphones deliver spam, and everyone knows the irritation of a face-to-face companion vanishing into his phone.
And then there's texting while driving, and dialling while crossing the street. Mr Cooper remembers that first call, in traffic, as "perhaps one of the most dangerous things" he had done in his life.
Mobile phones have come a long way since Mr Cooper's brick. Our tendency to behave recklessly with one in our hands, however, seems to be stuck in time.
