The science of speech. From The Mahabharata, Santi Parva.
King Janaka (the one mentioned in Bhagavad-gita by Lord Krishna): When the speaker, the hearer, and the words said, thoroughly agree with one another in course of a speech, then does the sense or meaning come out very clearly. When, in the matter of what is to be said, the speaker shows disregard for the understanding of the hearer by uttering words whose meaning is understood by himself, then, however good those words may be, they become incapable of being seized by the hearer.
That speaker, again, who, abandoning all regard for his own meaning uses words that are of excellent sound and sense, awakens only erroneous impressions in the mind of the hearer. Such words in such connection become certainly faulty. That speaker, however, who employs words that are, while expressing his own meaning, intelligible to the hearer, as well, truly deserves to be called a speaker. No other man deserves the name. It behoveth thee, therefore, O king, to hear with concentrated attention these words of mine, fraught with meaning and endued with wealth of vocables.
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