H is for…

Historical Moment
Back in the day (when I first encountered Silo’s teachings) you’d have found in materials of the time something like this:
An historical ambit in which several contemporary generations coexist. The hm is modified when the system of power is transferred from one generation to another. This transference can be done progressively (in which case, the determination of the change of the moment is not very obvious), or in a revolutionary manner.
Siloism, H. Van Doren: Aconcagua Press, 1972

Here’s the definition Silo left us with:
Every social situation finds itself in a determined hm wherein diverse generations coexist. An hm is differentiated from another when a “rupturist” generation disputes the power of the generation that holds it. Given a rupture, the conditions are present in the new hm for processing a new stage of greater breadth, or for the simple mechanics of the generational dialectic to continue. The hm appears as the minimal system (*) of a structure configured by the generations that coexist, in relationship with the structure of their corresponding sociocultural (*landscape) environment (*). Grasping this minimal system is necessary for the comprehension of a historical process. In other words: the coexisting generations and their surrounding landscape are the dynamic structures of the minimal system called hm

A Dictionary of New Humanism, in Silo; Collected Works Vol 2.