Post date: Jun 5, 2011 8:30:18 PM
One of the basic principles of human existence is that two people cannot occupy the exact same space at the same time.
When I was in the fifth grade we had to walk in single file everywhere we went. Sometimes I would watch my feet and try to step exactly where the person in front of me stepped. One time I was watching my feet like this and the line stopped without me noticing. I walked right into the person in front of me, the class bully. He immediately shoved me and I fell onto the cold linoleum floor. While the teacher was comparing our stories of what transpired I remember thinking: Why can't I walk through another person?
As a kid I was thinking of ghost-like abilities. The idea still haunts me: I cannot walk through walls or people. The barrier between each person’s idea of themselves and everything else is fundamental to the human condition. We figure it out as babies and rarely think of it again until our physical limits impede our ambitions.
My body creates the edge of my physical existence. My senses take me beyond my body: I can see other galaxies, I can hear thunderstorms on the horizon, and I can smell cookies baking the oven. My imagination has no limits, and my dreams take me to faraway places while my body sleeps in math class.
A shove from a bully and the impact of the linoleum floor brings me back to physical myself, though. It will take 3 days in a rocket ship to reach the nearest moon. The cookies that mom put on the top shelf are out of reach. Our bodies constrain us and those constraints are the basis for all the other rules.
Physics is the study of matter and energy. Those rules would be completely different if things passed through one another on a whim. More importantly, if people passed through one another at will then we might not try to figure out the interaction of matter at all! We would not try to understand the constraints if they did not exist.
The social laws we live by would be completely different if we could pass through each other. The law explains what you can do with yourself and your stuff, and limits what you can do to me and my stuff. If you could only hit me in the face if I chose to let you, then there would be no law against it.
I am here, you are there, and the space between us must be negotiated. This is a fundamental aspect of current human existence. It is a tenant of the social rules we create for one another. It colors our understanding of how the universe should work.