Recently a lot of new hardware has become available that gives computers numerous interesting ways of affecting the real world: making paper spew out of printers, causing words to appear on screens thousands of miles away, shooting beams of radiation through cancer patients, creating realistic moving pictures of the Titanic. Windows is now used as an OS for cash registers and bank tellers' terminals. My satellite TV system uses a sort of GUI to change channels and show program guides. Modern cellular telephones have a crude GUI built into a tiny LCD screen. Even Legos now have a GUI: you can buy a Lego set called Mindstorms that enables you to build little Lego robots and program them through a GUI on your computer.

So we are now asking the GUI to do a lot more than serve as a glorified typewriter. Now we want to become a generalized tool for dealing with reality. This has become a bonanza for companies that make a living out of bringing new technology to the mass market.

Obviously you cannot sell a complicated technological system to people without some sort of interface that enables them to use it. The internal combustion engine was a technological marvel in its day, but useless as a consumer good until a clutch, transmission, steering wheel and throttle were connected to it. That odd collection of gizmos, which survives to this day in every car on the road, made up what we would today call a user interface. But if cars had been invented after Macintoshes, carmakers would not have bothered to gin up all of these arcane devices. We would have a computer screen instead of a dashboard, and a mouse (or at best a joystick) instead of a steering wheel, and we'd shift gears by pulling down a menu:

PARK --- REVERSE --- NEUTRAL ---- 3 2 1 --- Help...

A few lines of computer code can thus be made to substitute for any imaginable mechanical interface. The problem is that in many cases the substitute is a poor one. Driving a car through a GUI would be a miserable experience. Even if the GUI were perfectly bug-free, it would be incredibly dangerous, because menus and buttons simply can't be as responsive as direct mechanical controls. My friend's dad, the gentleman who was restoring the MGB, never would have bothered with it if it had been equipped with a GUI. It wouldn't have been any fun.

The steering wheel and gearshift lever were invented during an era when the most complicated technology in most homes was a butter churn. Those early carmakers were simply lucky, in that they could dream up whatever interface was best suited to the task of driving an automobile, and people would learn it. Likewise with the dial telephone and the AM radio. By the time of the Second World War, most people knew several interfaces: they could not only churn butter but also drive a car, dial a telephone, turn on a radio, summon flame from a cigarette lighter, and change a light bulb.

But now every little thing--wristwatches, VCRs, stoves--is jammed with features, and every feature is useless without an interface. If you are like me, and like most other consumers, you have never used ninety percent of the available features on your microwave oven, VCR, or cellphone. You don't even know that these features exist. The small benefit they might bring you is outweighed by the sheer hassle of having to learn about them. This has got to be a big problem for makers of consumer goods, because they can't compete without offering features.

It's no longer acceptable for engineers to invent a wholly novel user interface for every new product, as they did in the case of the automobile, partly because it's too expensive and partly because ordinary people can only learn so much. If the VCR had been invented a hundred years ago, it would have come with a thumbwheel to adjust the tracking and a gearshift to change between forward and reverse and a big cast-iron handle to load or to eject the cassettes. It would have had a big analog clock on the front of it, and you would have set the time by moving the hands around on the dial. But because the VCR was invented when it was--during a sort of awkward transitional period between the era of mechanical interfaces and GUIs--it just had a bunch of pushbuttons on the front, and in order to set the time you had to push the buttons in just the right way. This must have seemed reasonable enough to the engineers responsible for it, but to many users it was simply impossible. Thus the famous blinking 12:00 that appears on so many VCRs. Computer people call this "the blinking twelve problem". When they talk about it, though, they usually aren't talking about VCRs.

Modern VCRs usually have some kind of on-screen programming, which means that you can set the time and control other features through a sort of primitive GUI. GUIs have virtual pushbuttons too, of course, but they also have other types of virtual controls, like radio buttons, checkboxes, text entry boxes, dials, and scrollbars. Interfaces made out of these components seem to be a lot easier, for many people, than pushing those little buttons on the front of the machine, and so the blinking 12:00 itself is slowly disappearing from America's living rooms. The blinking twelve problem has moved on to plague other technologies.

So the GUI has gone beyond being an interface to personal computers, and become a sort of meta-interface that is pressed into service for every new piece of consumer technology. It is rarely an ideal fit, but having an ideal, or even a good interface is no longer the priority; the important thing now is having some kind of interface that customers will actually use, so that manufacturers can claim, with a straight face, that they are offering new features.

We want GUIs largely because they are convenient and because they are easy-- or at least the GUI makes it seem that way Of course, nothing is really easy and simple, and putting a nice interface on top of it does not change that fact. A car controlled through a GUI would be easier to drive than one controlled through pedals and steering wheel, but it would be incredibly dangerous.

By using GUIs all the time we have insensibly bought into a premise that few people would have accepted if it were presented to them bluntly: namely, that hard things can be made easy, and complicated things simple, by putting the right interface on them. In order to understand how bizarre this is, imagine that book reviews were written according to the same values system that we apply to user interfaces: "The writing in this book is marvelously simple-minded and glib; the author glosses over complicated subjects and employs facile generalizations in almost every sentence. Readers rarely have to think, and are spared all of the difficulty and tedium typically involved in reading old-fashioned books." As long as we stick to simple operations like setting the clocks on our VCRs, this is not so bad. But as we try to do more ambitious things with our technologies, we inevitably run into the problem of: