Aircraft have a safety device called the ground proximity warning system. It alerts the pilot to the imminent danger of what is technically known as "controlled flight into terrain" or what we would call a crash. Aviation safety enthusiasts often morbidly discuss a possibly apocryphal remark made as a Colombian airliner approached Madrid's Barajas airport too low. After the accident, investigators discovered the cockpit voice recorder catching the synthesised voice of the GPWS (with its annoying North American accent) demanding: "Pull up! Pull up!" Seconds later, the same CVR caught the South American pilot, flushed with low-level machismo, saying: "Shut up, gringo." The next part of the transcript has the deathly words "sound of impact" in square brackets.

Technology is making our lives faster, moving us through both the real and virtual worlds. We can travel, both in body and mind, more often, with less expense and greater ease. But does technology also make us more stupid? In the beginning IBM, then a manufacturer of mainframes, adopted the slogan: "Machines should work. People should think." Fifty years on, that's a distinction no longer so clear. Is there an unspoken Faustian pact that we gain power at the expense of wisdom?

It's strange to ask such philosophically profound questions when toying with the latest touch-screen mobile, but let me tell you, thumbing through the garish Vodafone catalogue does inspire such speculations. When we hand over responsibility and knowledge to machines, do we also lose free will? Do sophisticated new technologies enhance our abilities while diminishing our intelligence? Does downloading an "app" of a spirit level on an iPhone (for about £0.59), let alone a virtual whoopee cushion, not only make us appear, but also become, stupid?

In the early days of in-car satellite navigation, German newspapers used to love running photographs of the roof of a BMW appearing just above the surface of the Elbe or Danube. The primitive mapping methods recorded only roads, not rivers. The result? Drivers slavishly obeyed instructions to "proceed for 10 miles" and then found themselves in the drink. As a result, today if you programme a satnav in England and set a destination in mainland Europe, the more ones will prudently say: "Warning! Channel crossing en route."

All new technologies, going back to fire and the wheel, by way of movable type and light bulbs, de-skill people. Old crafts are abandoned or lost in favour of automation. And when you de-skill someone, you alter not only his culture, but his personality. Satnav has done this to black-cab drivers. Once this proud tribe had a private religion known as the Knowledge; all of London's streets had to be memorised. It was an amazing feat achieved only after great effort, and consequently it was admired and therefore empowering and dignifying. The Knowledge gave black-cab drivers what the marketeers call a "point of difference".

Now any larrikin can buy a satnav for £199 and tell you how to get from Edmonton to Peckham by using rat runs. The USP of the black cab has disappeared in a miasma of pixels. As a result, some urban anthropologists have noted a change in behaviour of cab drivers. Once known for courtesy and reliability, many have become sullen and aggressive. This is because technology has democratised their proprietary knowledge and beliefs.

Or take your digital camera. Of course, it's a marvel, but while we have gained the ability to store and manipulate a thousand high-quality images at modest cost, we have lost something, too. The efficient operation of an old film camera required the user to have a working knowledge of the laws of optics; it was necessary to know about that strange, neo-mystical trade-off between shutter speed and sharpness. Taking a picture with a 35mm film camera employed physics and art. And since real expense was involved in getting a print, more care was taken throughout. "Painstaking" is not a word you associate with digital photography.

Then there is the phone. Your phone will have internet access. You can Google and Wiki your way through the world's great libraries and galleries while you are on the move or stupefied in bed. No one but a churl would deny that this is a benefit of nearly indescribable value, but it means "research" in the sense that, say, Sir Herbert Butterfield understood it has gone the way of the ducking stool and the chastity belt (but not yet Scottish country dancing). Who in their right mind would go to a library to check a date or a quote when they can be called up on the mobile or the laptop? I can hardly believe that I used to schlep to the British Museum or the London Library just to look something up.

The benefits are obvious but so, too, are the hazards. When we outsource all memory, will we lose our own? After all, memory and self-identity are inextricable. The brain is an organ and all healthy organs are improved by exercise. But there are mechanical as well as philosophical problems associated with the multiplication of ever more sophisticated technologies. I recently tried to alter the clock in an Audi Q5 and gave up in tears. In the United States, blind people have been run over by slow-moving and absolutely silent examples of the neo-electric Toyota Prius. Enhanced hygiene in healthcare has made patients more vulnerable to infections.

These perils of advanced technology are examples of the "revenge effect" described by Princeton academic Edward Tenner in his 1996 book Why Things Bite Back. Tenner also explained that the idea of advanced technology getting worryingly out of control goes back to Mary Shelley's Frankenstein, written against the background of Manchester's early-19th-century Luddite riots, where protesters smashed the new de-skilling technology of their day.

But contemporary Luddites, if there actually are any, appear silent in comparison. They are probably engrossed in their latest download. Certainly, there's a paradoxical character to technologies that makes you smarter and dumber simultaneously, but there are real new advantages, too. Actually, it wasn't all that great using the old Reading Room of the British Museum with its dogeared and yellow card index and malodorous tramps and weird opening hours. And while it is a legitimate source of anxiety that a future generation may receive a communications implant on birth and go through life with a phone number and not a national insurance number, they will learn new skills the while.

Bores say that kids today are becoming illiterate, but they are becoming literate in different ways. And more numerate, too, as Steven Johnson described in his 2005 book, Everything Bad Is Good for You. They process masses of new data at very high speed and develop extraordinary hand-eye co-ordination skills. They may not whittle sticks, but can programme machines and download software. Participation in the more sophisticated computer games calls for spatial awareness and imaginative skills beyond the reach of, say, an Italian architect of the 16th century. The haiku-like constraints of SMS force discipline, imagination and creativity. Email means people write more letters, they just don't happen to be on old-technology paper.

When we use the word "technology" today, we mean electronic communications, not steam or nuclear power. The great thing about all communications technologies is that none ever entirely supersedes its predecessor. Print did not replace writing and radio did not replace print. Books aren't going away. Technology is morally neutral - it's people who are not. Your phone won't make you stupid unless you want to be. Why not download an app on Attic Greek prose translation?