Anarchism is a creed inspired and ridden by paradox, and thus, while its advocates theoretically reject tradition, they are nevertheless very much concerned with the ancestry of their doctrine. This concern springs from the belief that anarchism is a manifestation of natural human urges, and that it is the tendency to create authoritarian institutions which is the transient aberration. If one accepts this view, then anarchism cannot merely be a phenomenon of the present; the aspect of it we perceive in history is merely one metamorphosis of an element constant in society.

The Family Tree - Anarchism : A History of Libertarian Ideas and Movements (1962)