The main thing is that it is green - or maybe BlueMotion, BlueTec, EfficientDynamics, CleanEnergy or driv-e. The future has an ear for these names ... of that there is no doubt. And, in the adverts of the car manufacturers, the future began a long time ago. It is hardly credible, how nice it will all turn out to be, how full of life, how jolly. All clean and green, of course.

Whether Honda conjure up life on the beach with family and friends for their new hybrid "Insight", or tell a 'little story about doers', where they suggest that it is just a matter of doing something, and all will be well - that bright, idealised world of the future is no more than the dream of our problem-laden present. And because everything sounds so reassuring, we are all supposed to become "doers", who always - how could it be otherwise - do the right thing. For let's be clear: we can all do something; we can check the tyre pressures, drive slowly, save petrol - except that what we mustn't do is do without the advert or do without buying a Honda car. Never mind all the things that have been wrought by 'doing' over the course of history - wipe the slate clean and paint it green!

In a similar way Toyota, too, conjures up the harmony of Man, Nature and Machine, so that everything blossoms, grows and turns green - like the fantasy of those in the car industry who are busy creating the future.

With Volkswagen, on the other hand, we discover that the present is as dark as a nightscape full of abandoned petrol stations, where shady figures stand guard just waiting for the time when, finally, we have to give up. But no worries ... our Polo doesn't use too much petrol, just keeps on going and going and going like, once upon a time, the proverbial Beetle. It's all so easy, this business of the green future.

From an aesthetic point of view, Audi also manages to present itself as progressive with regard to energy efficiency - and with a degree of panache. Instead of cars, light bulbs and strip lights glide through the city nightscape in crisp black and white. How beautifully they shine, float through the scene. Since it is an ad about a start-stop mechanism, the Audi light goes out when it stops - thus saving energy and petrol.

Not entirely without a catch, though. Whether it actually makes sense or not, tungsten light bulbs are just about to be banned in Europe. And so, you think: is this an advert for light bulbs? Or are cars just about to be banned like smoking or turning on the light? And wasn't it the very light that was so valued by the Age of Reason, celebrated by the Enlightenment, because it was to lead us out of the ignorance of our self-imposed immaturity?