Whoever uses machines does all his work like a machine. He who does his work like a machine grows a heart like a machine, and he who carries the heart of a machine in his breast loses his simplicity. He who has lost his simplicity becomes unsure in the strivings of his soul.
Chuang-tzu, 4th century BC, quoted in Morgan, 1986
To err is human but to really foul things up you need a computer
My students often groan when I tell them that this semester's timetable is to include human-machine interaction (HMI). I find this reaction puzzling because for every second of every day we are surrounded by machines of one sort or another. We live and work in buildings that are effectively machines in their own right. (If you doubt this, just wait until the plumbing decides to cease cooperating!) We use machines constantly, and frequently find the experience frustrating. The burnt dinner, the wrong programme recorded on the video, the car's lights left on and the battery flattened, the computer crash and work lost-the list of what can go wrong in our interactions with machines is endless. So wouldn't you think that the study of the design of machines to make them better fitted to our human capacities and limitations would be an interesting prospect?
Maybe many of us secretly harbour similar attitudes to machines as the Chinese sage quoted at the beginning of this chapter. Most of us tend to take it for granted when machines work properly and how they work is their affair-we neither know nor care. When they break down (which they always do eventually), we are filled with rage at our impotence in the face of this inanimate lump resolutely refusing to do our bidding. Somehow it is an affront to our human dignity-"Why won't this wretched computer do what I say!" It is also true that many people's working lives make them feel as if they are just parts of the machinery. A data entry clerk whose every keystroke, pause, and mistake is recorded by the computer, or the machine operator spending 8 hours loading and unloading a metal press, could be forgiven for thinking that the natural order of things had been overturned.