What is accessible and shared by all humans through common epistemic sources.
“Human Common Ground” here does not mean humanity in the moral sense, but rather the epistemic foundation shared by all: rules of reasoning and universally accessible sources such as direct sensory data, logic, and general experience. What depends on private sources (like religion or mystical insight) may be accepted by some but rejected by others, and thus lacks universality. The human common ground is therefore the neutral base from which everyone can begin without exception.
