Untranslatability of Theories with Different Vocabularies

The controversial idea of incommensurability in Kuhn’s works was gradually replaced by the translatability thesis, for which two distinct arguments could be formulated. The first is extracted from his theoretical contextual approach to meaning, and the second form his taxonomic conception of natural kind terms. According to each one, it could be given an untranslatability condition, in terms of which we can talk about untranslatability of theories with different vocabularies. I will formulate these untranslatability conditions in this essay, confessing that accepting these conditions will terribly limit the possibility of translation. On the other hand, the maxims critics of Kuhn suggested for translation involves a potential tension and fail to play the role a reliable maxim plays in a translation. In fact, within various versions of these maxims, there is a potential tension between maximizing rationality and maximizing truth in the original text that makes us suspect to follow them systematically.
Keywords: Incommensurability, Untranslatability, Classification of natural kinds, Principle of charity, Principle of humanity


Incommensurability, the most frequent term in debates on Kuhn, was not originally a homogenous term. In The Structure of Scientific Revolutions different meanings were meant by incommensurability, which can be distinguished in three types; epistemological, semantic and perceptual. In next writings, however, he restricted it in semantic type. But even this type was not a stable idea. While incommensurability was originally related to communication failure, it was connected then to untranslatability. In addition while he initially seemed to claim a total incommensurability between two theories with different vocabularies, in 1990s he restricted his claim to local incommensurability.
The terms he employed to explain incommensurability was not uniform too; in some cases it is formulated in terms of linguistic stuff like words, meaning and reference, and in other cases in terms of cognitive means like concept and classification. This difference leads to two different account of semantic incommensurability as untranslatability. What I’m concerned in this essay is the conditions for translatability which can be extracted from these two accounts. The first account is resulted from his contextual approach to meaning; a theory according to which meaning of a term is determined by its mode of application in that theory. Using conceptual role semantic the first condition for untranslatability can be articulated:First condition: two theories are untranslatable if and only if scientific laws and possible inferences in two theories do not correspond.
I employ this condition to show that why P. Kitcher’s response (1978) to Kuhn on theories in different sides of chemistry revolution in 19th century does not work. This condition, however, is too strong, respecting which not only revolutionary theories, but also most different theories are impossible to be translated.
The second account concentrates on concepts arranged in scientific classifications. This account seeks to exhaust content of a theory by classification, which includes an arrangement of specific categories with interconnected relations. Now the second condition can be introduced:Second condition: two theories are untranslatable if and only if there are cross-classifications between natural kinds in their domain.
As Career (2001) indicated this condition is neither necessary nor sufficient. It is not necessary because two conceptual systems may be untranslatable without violating principle of non-overlap in their lexical structure. It is also not sufficient, because the overlap between two taxonomies might be such that it can be amended and turn out to be consistent. This condition is weaker that what Kuhn needs to claim incommensurability between theories.
Then I attempt to show that while translation conditions are articulated, Kuhn's account of incommensurability requires more articulation, maxims for translation introduced by Kuhn’s critics, like Putnam (1980) and Davidson (1991) suffer from an essential tension which frustrates their projects. According to Davidson a translation must care a principle called principle of charity. This principle includes two distinct principles; according to first one, i.e. principle of coherence, the translator must maximize logical consistency in speaker’s thought. According to second principle, i.e. principle of correspondence, he must understand the speaker such that he is responding to the very features of the world to which the translator would respond in similar circumstances. By first principle the speaker seems to be almost rational, and by the second the translator attributes to the speaker some of what he considers to be true about the world. The principle of charity is result of two concerns; inferential concern and representational concern. Now the question is what should we do when these two maxims diverge; i.e. the inferential concern is in different direction from representational concern? Especially when there is no doubt, regarding pervious theories, that they are partially true. As was said, Kitcher’s question was to give instructions to determine how much Prestley says really. In fact, there is a way to separate items with a reference to the use of a phrase from non-reference items. In his current statement, his focus was on principle, with the aim of separating sentences which are based on the theory of the next. But I think that pursuing this concern will amount to a violation of the principle of solidarity. The principle of Putnam's Guide, by giving priority to the transfer and preservation of our concept of one thing in relation to our perception of it, inevitably makes the scientist's rationale sacrificed for the concept of its vocabulary. Davidson has also deliberately articulated two principles in his formulation of the principle of good faith.
- Carrier, M. (2001) 'Changing Laws and Shifting Concepts: On the Nature and Impact of Incommensurability' in Boyd, R. Hoyningen-Huene, P. Sankey, H. (2001) Incommensuraibility and related matters, Springer.
- Davidson,D. (1991)'Three Varieties of Knowledge', Royal Institute of Philosophy Supplement, 30, pp 153-166.
- Kitcher, P. (1978) 'Theories, theorists, and Theoretical Change', The Philosophical Review, Vol. 87, No. 4 (Oct. 1978), pp. 519-547
- Kuhn, T. S. (1970) The Structure of Scientific Revolutions, Chicago: University of Chicago Press, 2nd ed.
- Putnam, H. (1981) 'Two conceptions of rationality' in Reason, Truth and History, Cambridge, Cambridge University Press