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Observational conditional/(s)/Definition Test/Physics/Field: physical theories are tested, in which consequences are derived via observables from premises via observables. - Sure, we also refer to the unobservable.
Verification/Axiom/Theory/Field: E.g. "verifiable" is part of a theory that does not yet have the new axiom.
Verification Conditions/Verification/Verificationism/Field: Verfication conditions (perhaps via stimuli) are given without that-clauses. - So without propositional content. - Then we have classes of verification conditions instead of proposition. - Inflationism: would say that these are not proper propositions because these must include truth conditions. - InflationismVsVerificationism.
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