It will happen across such a long and large gradient that no one will know or ever understand it.

Does a single ant “know” what the whole colony wants? Yet one can describe the colony as a whole in many ways: finding food, reacting to threats, etc.

Does a single neuron “know” it is part of a brain? Yet the brain acts as a system, responding to stimuli in a coordinated fashion.

Hypothesis: we are already “one”, we just don’t know it, and can never truly know it, at an individual level.