Whitman did not limit his poetry to learned sources and books; he referred to street language and daily life as its linguistic source. He tried to invigorate American English and poetry through “the rich flashes of humor and genius and poetry – darting out often from a gang of laborers, railroad-men, miners, drivers or boatmen!” (Hoffman 369). He preferred “the ordinary language of American conversation with a strong mix of foreign terms, colloquialisms, place names, technical terms, slang, and new words he creates himself with innovative uses of prefixes and endings” (Killingsworth, The Cambridge Introduction to Walt Whitman 27). He strongly believed in slang as “the start of fancy, imagination and humor” (Hoffman 369). Furthermore, in An