Behind the claim that sound is eternal appears to be the idea that it must be eternal because the utterance of the word is for the purpose of another. Without this eternality, one person could not make anything known to another, because once the word was spoken, it would no longer exist. Another reason why sound is seen as eternal is to validate the authority of the Vedic scripture, and to show that it is itself eternal.
In this essay I will examine this claim that the word (or sound) is eternal, as set out in the Mimansa, and also the objections to this as set out in the Nyaya (Sourcebook, 1957, pp488-501). I believe that the Mimansa view makes a lot of sense, and although it perhaps seems strange to say that sound is eternal, it does explain how we can form relations between words and groups of words. It also explains how we know a word is the same word each time we hear an utterance of it, and do not believe it to be a new and different word.
[...] The Nyaya take this as evidence that sound is not eternal, but the Mimansa school believe that it is just that sound is in an unmanifest, imperceptible form most of the time. It does not become perceptible until the utterer of the sound comes into contact with the object, namely the sound. The Mimansa philosophers go on to say how this idea works (Sourcebook p490). They say that we recognise a sound, for example to be the same each time we hear it, and the easiest way to account for this is that sound is eternal, and is just unmanifest between utterances. [...]
[...] For if this is thought about, it seems slightly absurd to say that we ‘create' a sound, because creation suggests making something new, and if this were the case the utterance would not be understood, but it invariably is understood and recognised as a previously established sound. The objection involving simultaneity of sounds is explained through an analogy with the sun. It says that the sun is one thing but looks as if it is occupying many places at once. [...]
[...] The Nyaya believes that this shows the Mimansa theory that sound is just manifested by human effort, and not produced, to be wrong. This is because even a thousand manifesters cannot increase the object that they manifest. They support this by saying that even a thousand lamps do not make a jar larger. Furthermore, it would seem that if sound were just manifested, the sound produced each time would be identical, and because it is not, the sound must at least be partly produced by the person. [...]
[...] I would agree with the Mimansa that it is fact the ‘noise' rather than the sound that is increased. The word ‘noise' in this case refers to the conjunctions and disjunctions of air. The noise increases because more of these conjunctions and disjunctions enter the hearer's ear at the same time, and so the sound is louder, rather than the sound being multiplied into multiple entities. It is just multiple manifestations of the word as a whole. One of the most important arguments in the Mimansa is that sound must be eternal to fulfil the purpose of giving knowledge from one person to another. [...]
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