Radical translation

Radical translation is a thought experiment in Word and Object, a major philosophical work from American philosopher Willard Van Orman Quine. It is used as an introduction to his theory of the indeterminacy of translation, and specifically to prove the point of inscrutability of reference. Using this concept of radical translation, Quine paints a setting where a linguist discovers a native linguistic community whose linguistic system is completely unrelated to any language familiar to the linguist. Quine then describes the steps taken by the linguist in his attempt to fully translate this unfamiliar language based on the only data he has; the events happening around him combined with the verbal and non-verbal behaviour of natives.

As a first step, the linguist will use direct translation on occasion sentences. Hearing a lot of utterances of the one-word-sentence 'Gavagai' whenever the linguist sees rabbits, he suspects the one-word-sentence 'Rabbit' to be the correct translation and starts a process of questioning and pointing until he is reasonably certain that the native has the verbal disposition to assent to 'Gavagai' if seeing the stimulus, a rabbit. This stimulus is the affirmative stimulus meaning of 'Gavagai', and the linguist can conclude this is a correct translation.

The translation of occasion sentences may be complicated through collateral information. A native, with full expertise of his surroundings, may already assent to 'Gavagai' when not even seeing a rabbit, but is sufficiently satisfied to assent when spotting a specific rabbit-fly that only flies around rabbits. The linguist on the other hand has no such expertise, and will wonder why his hypothesis seems off. Collateral information can also create a difference of stimulus meaning between members of the same language community. To solve this issue, the linguist will determine intrasubjective stimulus synonymy, enabling him to pair non-observational occasion sentences such as 'Bachelor' and 'Unmarried man'. While they may differ in stimulus meaning between various speakers, they are stimulus synonymous for the entire language community.

It is also possible for the linguist to determine stimulus analytic sentences, to which the native will assent given any (or no) stimulus. Social analytic sentences are sentences that are stimulus analytic for the entire language community.

So far the linguist has taken his first steps in the creation of a translation manual. However, he has no idea if the term 'gavagai' is actually synonymous to the term 'rabbit', as it is just as plausible to translate it as 'one second rabbit stage', 'undetached rabbit part', 'the spatial whole of all rabbits', or 'rabbithood'. To question these differences, the linguist now has to translate words and logical particles.

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