Davidson and the omniscient interpreter

Davidson’s philosophy of language is based on the thought experiment of radical interpretation: interpretation from scratch. It is a philosophical abstraction from the kind of interpretation undertaken by a field linguist having first contact with an alien tribe. Such interpretation - it is assumed - cannot appeal to bilingual speakers or dictionaries. It precedes those resources. Furthermore, according to Davidson, it cannot make substantial use of the content of the mental states of speakers. Whatever the connection between mental content and linguistic meaning, radical interpretation must earn access to, and cannot simply assume, facts about both. Interpretation must, instead, rely only on the evidence of correlations between utterances and the circumstances which prompt them. Davidson also thinks that, ultimately, facts about mental content have to be determined in the same way. Meanings and belief contents are interdependent. This presents a principled difficulty for radical interpretation:

‘A speaker who holds a sentence to be true on an occasion does so in part because of what he means, or would mean, by an utterance of that sentence, and in part because of what he believes. If all we have to go on is the fact of honest utterance, we cannot infer the belief without knowing the meaning, and have no chance of inferring the meaning without the belief.’ [Davidson 1984: 142]

Thus the interpreter faces the task of unravelling two sets of unknowns - facts about meaning and facts about beliefs - with only one sort of evidence: linguistic actions which depend on both meaning and belief. How can the interpreter - to change the metaphor - break into this interdependent set of facts?

Davidson’s solution has two ingredients. Firstly, he takes the evidential basis of radical interpretation to be the prompted assent of a speaker, which he characterises as ‘the causal relation between assenting to a sentence and the cause of such assent’ [Davidson 1983: 315]. It is possible to know that a speaker assents to a sentence without knowing what the sentence means and thus what belief is expressed by it (or vice versa). Characterising a speaker as holding a particular sentence true is an intentional interpretation of what is going on - the speaker is described by relation to a propositional content - but it does not presuppose a semantic analysis of the sentence. That will be derived later.

The second step is to restrain the degrees of freedom of possible beliefs in order to interpret linguistic meaning. The interpreter must impose his or her own standards of truth and coherence on ascriptions of beliefs and meanings. There must be a presumption that any utterance or belief held true really is true. Further, in a significant range of cases, the interpreter must assume that the object of an utterance, and the belief the utterance expresses, is the cause of the utterance and belief. This complex of related assumptions governing the rationality imputed - generally briskly labelled the Principle of Charity - enables interpretation to get off the ground. If utterances are assumed by the interpreter to be generally true and to concern the worldly states of affairs which prompt them, then they can be correlated with those observed states of affairs. Their meaning can thus be determined. Given an overall interpretation, exceptional false beliefs can then be identified.

This approach to belief and meaning has an additional feature, according to Davidson. It is proof against scepticism. To push this point home he considers and omniscient (all knowing) interpreter. But does this argument work?

Essential reading (look on Blackboard)

- Davidson, D. (2010) 'A coherence theory of truth and knowledge' in Sosa et al (eds) Epistemology: an anthology, Oxford Blackwell