perceptionism
/pəˈsɛpʃ(ə)nɪz(ə)m/ /pəˈsɛpʃənɪz(ə)m/Philosophy rare
noun
The theory that all knowledge derives ultimately from sense-perception. Also: the theory that everything can be explained by human perceptions of reality rather than by external reality.
Origin
Late 19th century; earliest use found in Alexander Beresford-Hope (1820–1887), politician and author. From perception + -ism.