Nobody debated the reality of gods to whom they sacrificed first born male children.
Nothing much changed in life, the seasons followed the path predicted by the priests who performed the calculations, the rituals and sacrifices, as decreed by authorities or demanded by gods.
The collective social environment, daily life, interacted causally with metaphysical reality,
Sumer lived by the code of Hammurabi, citizens paid taxes, made bloody sacrifices and prospered between calamities if fortunate enough to possess “me”.
A me is a competence conferred by a god. The me are social capacities, instruction sets, programs foundational to civilization.
A me is the knowledge necessary to construct a musical instrument and the ability to play it.
A me might also be a means of Holy purification, skill in Metalworking or Scribeship. Over a hundred me are mentioned in later Sumerian mythology, though only 60 remain to us today; they are listed here.
http://www.angelfire.com/tx/tintirbabylon/ME.html
Aggregated me form a culture genome, each individual me a cultural competency necessary to the survival of the civilization. The me have a peculiar form of delivery: a Nam Shub; a verbal or written incantation, the Nam Shub of Enki, a Sumerian god, is “both a story of linguistic disintegration and the cause of that disintegration.”
“Once upon a time, there was no snake, there was no scorpion,
There was no hyena, there was no lion,
There was no wild dog, no wolf,
There was no fear, no terror,
Man had no rival.
In those days, the land Shubur-Hamazi,
Harmony-tongued Sumer, the great land of the me of princeship,
Uri, the land having all that is appropriate,
The land Martu, resting in security,
The whole universe, the people well cared for,
To Enlil in one tongue gave speech.
Then the lord defiant, the prince defiant, the king defiant,
Enki, the lord of abundance, whose commands are trustworthy,
The lord of wisdom, who scans the land,
The leader of the gods,
The lord of Eridu, endowed with wisdom,
Changed the speech in their mouths, put contention into it,
Into the speech of man that had been one. “
A Nam Shub is a text which specific properties; is self-reflexive, it’s about itself, and which can’t merely be read or listened to, it must also be obeyed, as in the song the Sirens sung:
Sweet coupled airs we sing.
No lonely seafarer
Holds clear of entering
Our green mirror.
(Homer, The Odyssey, Book 12, 173-176)
The me share similarities with the antigens in our immune system which warn of and describe enemy viruses, ordering the construction of antibody weapons to destroy them.