Relation-Theory: takes belief to be a relation to internal objects (entities). Virtually all authors are against the assumption of thoughts as internal objects. See also intensional objects, intensions, propositional attitudes, mentalism.
Relational Theory/Bigelow/Pargetter (Science and Necessity Cambridge University Press 1990 p55) assumes universals (e.g. sets, numbers, properties) and relations between them in order to explain the problem of quantities. See also change, motion, quantities, universals, Platonism, nominalism.
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Relation Theory/Schiffer: "There is something that he believes" - can only be closed with referential quantification (not with substitutional quantification) . - Substitutional Quantification: is true if a substitution instance of "Elmar believes that S" is true. - Referential Quantification: "..believes x" whereby an x must exist. - Substitutional Quantification: no relation theory because the substitutioanl quantification is consistent with every representation of the logical form of substitution instances that make quantification true.
Relation Theory/Schiffer: Relation to sentences: Davidson (1969): to the public language of the attributing - Carnap (1947): to the public language of the believer - Loar: public language of the attributing, but the semantic attributes (which determine the content) are in the Tarski-style (non-public) - then nothing about the role of expressions or use in population. - Problem: then beliefs must be individuated by interpersonal functional states - that does not work with Tarski.
SchifferVsPropositionalism/VsRelation Theory with proposition as an object: if true, the proposition would include as content either dog property itself (does not work because of shmog) or way of givenness (GW) of it. - way of givenness: We have no clue what they should be. (+)
Relation Theory/Schiffer: here for representation (= sentences) in mentalese (instead of propositions). - Meaning in mentalese determines meaning in public language, not vice versa. (+)
Remnants of Meaning Cambridge 1987