In computing with words and perceptions (CWP), the objects of computation are words, perceptions, and propositions drawn from a natural language. The central theme of CWP is the concept of a generalised constraint. The meaning of a proposition is expressed as a generalised constraint.
CWP is a necessary tool when the available information is perception-based or not precise enough to use numbers.
References
Computing with words and perceptions Wikipedia(Text) CC BY-SA