Speed is the defining characteristic of our age. Above all we go faster than our ancestors - until the steam train no-one had ever gone faster than a galloping horse. (Unless they fell off a high cliff I suppose.) And we praise speed in sport, in business and in travel. It's no surprise then that George Osbourne's latest wheeze for reviving the economy is HS3, a high-SPEED rail line across the north of England.
Yet 'speed kills', speed is dangerous. Fast cars cause accidents. Fast decisions overlook inconvenient facts. And friction means that high speeds waste more energy than low speeds.
The Green movement knows this and has lobbied for lower speeds on roads and against high-speed rail on the grounds of energy and safety. But there's more to it than that. There are activities that are better if they're slower. Eating, drinking and lovemaking for just three. In fact most social activities are better if they're not rushed.
And this is one key to creating a better society. When we ask for speed limits we're making the street more accessible to those, children and the elderly, who aren't fast. We're also making the streets a more natural place for social contact. When we oppose high-speed rail we're also asking people and planners to focus on their local economies and suburbs.
And in all we're striving for a society that cares more for the relationships between its people than for the speed of its machines. A society in which people sustain each other and in which our demands are such that the Earth can sustain us; and our children.
For more on this see Carl Honore's TED talk.