ABSTRACT
The schemas described in Chapter 8 are of one particular kind among many. 1 They are mental models embodying selected features of the outside world. Even at a common-sense level, they greatly increase our power to understand, predict, and control events in the physical world. These common-sense schemas represent for the most part objects and events directly accessible to our senses. We use them for our everyday living in much the same ways as mankind has done before us for thousands of years. But the word processor on which I am writing this chapter cannot be understood at a common-sense level. It is a product of manufacturing techniques derived from mental models of objects and events far beyond the reach of our senses. Yesterday evening, on a similar cathode ray tube in our living room, we watched pictures of the planet Uranus and its moons, transmitted back to Earth over many millions of miles by the space craft Voyager 2. Mental models of this kind are a relatively recent arrival in our history. The uses to which we put them fall into the same groups as have already been described in Chapter 8, pages 111 ff.: but their power and sophistication enable us to attain goals that would have been thought impossible until recently.
