Davidson, Indeterminacy, and Measurement

Abstract

Donald Davidson has recently announced his endorsement of the ‘measurement theory’ (MT) of propositional-attitude ascription (PA-ascription). Proponents of the MT hold that “to say that a subject has a certain propositional attitude...is to attribute to that person a certain psychological state which is specified by means of its location in a measurement space, in just the way that we specify the temperature of an object by means of its location on a measurement scale.”1 The MT contrasts with the view that the attitudes are relations between cognitive agents and semantically evaluable entities that furnish the intentional objects of the attitudes. This is not to reject a relational semantics for sentences ascribing propositional attitudes. Indeed, Davidson himself has argued that only such a semantics, which treats verbs of propositional attitude as two-placed predicates taking as arguments a cognitive agent and a’content sentence’, can accommodate PA-ascriptions in a compositional theory of meaning for a language. What the measurement theorist denies is that our ascript ive p ract ices commit us to v iew i ng the att itudes themselves as relational in the foregoing sense. To say that S has a certain propositional attitude is no more to say that S stands in a causally pregnant relation to a proposition than to say that X weighs 10 grams is to say that X stands in a causally pregnant relation to the number 10, according to proponents of the MT.