We have to understand the context

From E.D. Hirsch's Cultural Literacy.

The recently rediscovered insight that literacy is more than a skill is based upon knowledge that all of us unconsciously have about language. We know instinctively that to understand what somebody is saying, we must understand more than the surface meanings of words; we have to understand the context as well. The need for background information applies all the more to reading and writing. To grasp the words on a page we have to know a lot of information that isn't set down on the page

.