Renato Poggioli’s Theory of the Avant-Garde (1968) identifies the ideological and mythic building blocks of the avant-garde more or less as follows.
An avant-garde is a movement, one that has identified an enemy – the public, popular culture, the old, tradition, institutions – and is dedicated to destroying it and bringing about an improved future, usually indicated by an “ism” of some kind and explained in a manifesto. It acts with a spirit of adventure, but it also suffers for the cause, which the public inevitably fails to appreciate. Avant-gardes are alienated from all aspects of society, culture, popular taste, and style. They condemn and denounce, using images of revolution, subversion, violence, and destruction. They shamelessly proselytize and promote themselves, advocating experimentation in technique and form and tending towards hermeticism, obscurantism, exhibitionism, and shock.