Epistemology
The word "epistemology" is derived from the ancient Greek "epistēmē" meaning "knowledge" and the suffix "-logy", meaning "logical discourse" (derived from the Greek word "logos" meaning "discourse"). It is analogue to the German "Wissenschaftslehre" (literally, theory of science) which was introduced by philosophers Johann Fichte and Bernard Bolzano in the late 18th century. The word first appeared in English in 1847 as a translation of the German in New York's "Eclectic Magazine" review of a philosophical novel by German author Jean Paul:
Deductive-nomological model
Natural laws, so called, are statements of humans' observations, thus are epistemological—concerning human knowledge—the "epistemic". Causal mechanisms and structures existing putatively independently of minds exist, or would exist, in the natural world's structure itself, and thus are ontological, the "ontic". Blurring epistemic with ontic—as by incautiously presuming a natural law to refer to a causal mechanism, or to trace structures realistically during unobserved transitions, or to be true regularities always unvarying—tends to generate a "category mistake".