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Norm/Belief/Possible World/Field: Norm and belief must be distinguished by itself. If the acceptance of a norm is merely a belief of something (e.g., that action is correct according to it), then the information that is relevant for the truth value of belief (belief) must be contained in the possible world itself - then the norm is no longer required for the assessment of the mental state - norm: must be part of a possible world which is independent of belief.
Norm/non-factualism/Field: thesis: norm-sensitive utterances (which contain evaluative predicates) are only true relative to norms - factualism: limits that to the norms which are not objectively false - non-factualism/factualism: are differentiated by the fact, which statements are - "simply true" (i.e. true in all norms that are not objectively wrong). - analog: (see above) dft-operator to amplify "true" in vagueness.
Norm/Ethics/disagreement/dispute/N.B: If there is no norm-sensitivity in a sentence anymore, then a contradiction between norms can no longer count as a contradiction ((s) between sentences).
Ethics/Field: Dispute only exists about attitudes, not about facts - Problem: having an attitude is not sufficient, but accepting a reference system is necessary. - (analog: having time order is not sufficient).
Realism, Mathematics and Modality Oxford New York 1989
Truth and the Absence of Fact Oxford New York 2001
Science without numbers Princeton New Jersey 1980