chemist vs Paul Hermann Muller

chemist and Paul Hermann Muller both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemist	Yes	No	No	No
Paul Hermann Muller	Yes	No	No	No

chemist (noun)	Paul Hermann Muller (noun)
a scientist who specializes in chemistry	Swiss chemist who synthesized DDT and discovered its use as an insecticide (1899-1965)
a health professional trained in the art of preparing and dispensing drugs