The A A, whose name is rendered Astrum Argenteum or Argenteum Astrum, the Silver Star, is built on an organising principle that sets it apart from the lodge orders it grew out of.
Each knows only two
Founded around 1907 by Aleister Crowley and George Cecil Jones after the collapse of the Golden Dawn, the order runs on the grades of the Tree of Life and on solitary work under a single superior. Each member knows only the person who introduced them and those they in turn introduce, so the order has no meetings, no visible membership and no assembled body: it exists only as a set of one-to-one links. The syllabus was published openly in The Equinox, the periodical edited by Crowley, which is the paradox of the thing, an order whose curriculum is public and whose structure is invisible.
What the design assumes
The arrangement places the entire weight of authority on the individual teacher-student bond and on the claimed attainment of the superior, since there is no assembly and no external check. Several lineages claim descent from the original body, and there is no institution above them able to adjudicate the claims, which is a direct consequence of the way the order was designed.