The purpose of figurative communication is to achieve true consensus which means achieving a rational, emotional and conceptual consensus.
Achieving true consensus requires solving the conflicts which might be driven by interests, needs, beliefs, lack of knowledge, etc.
Metaphors are universal descriptions using analogous examples at a more general field that allow understanding the message that is being communicated.
Metaphors have only one functional interpretation that ensures that the communication is true. Metaphors are necessary to work with complex problems at an operational level.
The metaphors used by the extreme programming methodology show an example of their use. Metaphors focus on the operation of what is being communicated.
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