听力文本：

The way we see things is affected by what we know or what we believe. For those who believed in the physical existence of Hell in middle ages, the sight of fire must have meant something different from what it means today. Nevertheless their idea of hell owed a lot to the sight of fire consuming and the ashes remaining as well as to their experience of the pain of burns.
We only see what we look at. To look is an act of choice. As a result of this act, what we see is brought within our reach, though not necessarily within arm's reach. To touch something is to situate oneself in relation to it. We never look at just one thing; we are always looking at the relation between things and ourselves. Our vision is continually active, continually moving, continually holding things in a circle around itself.
Soon after we can see, we are aware that we can also be seen. The eye of others combines with our own eye to make it fully clear that we are part of the visible world.