Most scholars would agree that modernism began around 1900 and continued on as the dominant cultural force in the intellectual circles of Western culture well into the mid-twentieth century.: "is [... primarily located in the years 1890-1930 [...]"</ref> Like all eras, modernism encompasses many competing individual directions and is impossible to define as a discrete unity or totality. However, its chief general characteristics are often thought to include an emphasis on "radical aesthetics, technical experimentation, spatial or rhythmic, rather than chronological form, self-conscious reflexiveness" as well as the search for authenticity in human relations, abstraction in art, and utopian striving. These characteristics are normally lacking in postmodernism or are treated as objects of irony.