This video shows 32 metronomes synchronizing on a surface that responds to their oscillation. (They won't synchronize on a rigid surface.)
Christian Huygens noticed in the 1600s that pendulum clocks on the same wall synchronized, because the wall responded to the pendulums.
As long as the springs powering the metronomes don't run down, and the suspension of the table doesn't wear out, the synchronization we witnessed is both irreversible and spontaneous. It's a provocative and visual demonstration of an emergent order, given a flow of energy through the system from the wound-up springs of the metronomes.
The processes of life can work like this. But we may have trouble grasping it, and instead default to some kind of conspiracy theory.
The suspension or responsiveness of the table is a crucial element. For people, a rigid or inflexible environment, where power is seldom shared, is not conducive to consensus.
See also a simple model of flocking behavior here, where each bird or creature has 3 behaviors: avoidance, alignment, and coherence. These models also appear to resemble social and neurological phenomena.