As social relations become vertical, it influences the development of religion and politics, giving us, you guessed it, vertical religion and vertical politics.
In Wandering God, Morris Berman writes:
“… under what would become the stress and insecurity of Neolithic life, what is a natural spiritual life — love of the world as it presents itself — moves aside to make way for the shaman, for ecstasy, myth, ritual, charisma, and in general, vertical religious experience. The fear of death that is generated by that life, and the altered child-rearing practices that often accompany it, make transcendent solutions (and explanations) increasingly attractive.”
As the till-plant-harvest process ramps up, more people start living in smaller areas, sharing their living quarters with domesticated animals. This closeness creates a utopia for ambitious germs that spread their germ-y self all over the place.
This contributes to disease and food insecurity. In short, the world becomes filled with uncertainties.
And here we have our motive. “(T)ranscendent solutions (and explanations)” become “increasingly attractive.” Vertical religions and their necessary sidekicks, vertical politics, build up those explanations.