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Theoretical Terms / Theoretical Entities / Rationality / Fraassen: the attitude of "maybe there are no electrons" (> Vaihinger). This assumption is more cautious. - But this is merely a methodological matter. - Neither empirical nor logical deductive - simply logically weaker. - Therefore, it can not be less plausible. - Putnam: now shifted intention from electrons to demons - Putnam: There can be theories that match the empirical content, but differ in the truth value.
Observability / Theoretical Entities / Fraassen: error: to assume a continuity here. - (E.g. giant crystals are observable) - Solution: th.e. are also clusters of th.e. - E.g. the table as a cluster of molecules. - (Logically trivial).
B. van Fraassen
The Scientific Image Oxford 1980