observationalism
/ˌɒbzəˈveɪʃ(ə)nəlɪz(ə)m/ /ˌɒbzəˈveɪʃn(ə)lɪz(ə)m/ /ˌɒbzəˈveɪʃ(ə)nəlɪz(ə)m/Philosophy
noun
The theory that all knowledge is based on observation. Also: the belief that observation, rather than theory, is the basis of science. In recent use in the arts, and especially in film: a strictly factual and descriptive approach to documentary narrative.
Origin
Late 19th century; earliest use found in Henry Calderwood (1830–1897), philosopher. From observational + -ism.