Outside all of us lies the same cold, sterile external physical reality, the statistical, relativistic, mechanistic universe of matter, energy, space and time. Inside, each of us is at the center of his own rich and layered human reality, one no doubt based on that external world, but very different in character and texture. This is the world we have to function in, the universe that we perceive with our senses, map with our reason and can affect through our actions. And we all live in different versions of that universe, versions that may overlap and share some common features, but each nonetheless distinct and personal.

The fisherman knows how to sail his boat and keep it in good repair, knows which sea creatures are dangerous and poisonous, knows how to avoid pirates and he's a good swimmer. He can also mend nets, hold his own in a waterfront tavern brawl, or bargain a good price for his catch in the market.

The courtier knows palace politics, how to charm the ladies by playing his lute and dancing the minuet, how to handle a rapier, and how to dress to impress the king and his ministers, and which scullery maid can be bribed safely to get useful gossip..

Each has equally legitimate survival skills to navigate and exploit his own personal subjective environment and to survive in it. Neither has any use for the skills and knowledge of the other, and in fact, probably has nothing but contempt for them. And neither needs to know whether Ptolemy, Kepler, Galileo, Newton or Einstein had the right cosmology. The "real world" has a lot more to do with who YOU are than what IT is. You may argue I have "rigged" my metaphor in order to prove my point, but that is exactly my point. The human mind is designed to rig its metaphors of reality in order to function effectively in a physical universe it simply is not equipped to fully understand.

Democritus was only partially right, everything we see and live is only by convention, by personal imagination and individual creation, and perhaps mutual agreement with our fellows. It is only outside our consciousness that 'nothing really exists but atoms and the void'.