Abstract
In scientific and technical communication, intelligibility is primarily a cultural problem, to which carefully formulated generalizations, rather than streams of data, are the only solution. Preoccupation with simplicity, or clarity, or `correctness' is a poor substitute for a careful consideration of what the reader can and cannot be expected to understand. The writer who will overcome his prejudices against generalization in order to convey the concepts which his reader does not share with him should be able to communicate more effectively at three levels: (1) to his fellow specialists, (2) to specialists in other fields, and (3) to concerned laymen.