How do you know a translation was successful

As the goal of translation is to ensure that the source and the target texts communicate the same message while taking into account the various constraints placed on the translator, a successful translation can be judged by two criteria:

1. Faithfulness, also called fidelity, that is the extent to which the translation Accurately renders the meaning of the source text, without adding to it or Subtracting from it, and without intensifying or weakening any part of the Meaning.

 
2. Transparency, which is the extent to which the translation appears to a native speaker of the target language to have originally been written in that language, and conforms to the language's grammatical, syntactic and idiomatic onventions.

A translation meeting the first criterion is said to be a "faithful translation" a translation meeting the second criterion is said to be an "idiomatic translation".

The criteria used to judge the faithfulness of a translation vary according to the subject, the precision of the original contents, the type, function and use of the text, its literary qualities, its social or historical context, and so forth it need to have perfect valid qualities. The criteria for judging the transparency of a translation would appear more straight forward: an unidiomatic translation "sounds" wrong, and in the extreme case of word-for-word translations generated by many machine translation systems, often result in nonsense.

Nevertheless, in certain contexts a translator may knowingly strive to produce a literal translation. For example, literary translators and translators of religious works often adhere to the source text as much as possible. To do this they deliberately "stretch" the boundaries of the target language to produce an unidiomatic text. Likewise, a literary translator may wish to adopt words or expressions from the source language to provide "local color" in the translation.

The concepts of fidelity and transparency are looked at differently in recent translation theories. The idea that acceptable translations can be as creative and original as their source text is gaining momentum in some quarters.

The concepts of fidelity and transparency remain strong in Western traditions, however. They are not necessarily as prevalent in non-Western traditions. For example, the Indian epic Ramayana has numerous versions in many Indian languages and the stories in each are different from one another. If one looks into the words used for translation in Indian (either Aryan or Dravidian) languages, the freedom given to the translators is evident.