On an airplane I prefer the window seat. I like to watch the tarmac fall away as people shrink to ants and buildings press-down flat. At a certain point everything looks the same. The Earth is the Earth, and whatever is below me could be Milan or Kenosha and I wouldn’t know the difference, I simply wouldn’t be able to distinguish them.
This is sort of what the cosmological principle tells us. If we were in an omnipotent airplane traveling through the Universe, we could fly ‘high’ enough to a certain point where our perspective would be so zoomed out that everything would begin to look the same. This implies that there is no special corner of space, and furthermore, that we are not special.
This keeps me up at night. With a hot cup of peppermint tea and cold feet shoved into mismatched socks or faded-wool slippers. With knees pressed to my chest, eyes out the window, elbows on the table. The heartbreak of homogeneity was my first great perspective change, one that is on-going and (at times) excruciating. Like lying on a cold tile floor at the end of a long day, there’s only so much you can do to make yourself feel better about something so out of your hands.
The Universe is homogenous and isotropic, this is the cosmological principle. It’s homogenous, meaning no preferred observing position or center, and it’s isotropic, meaning the same in all directions. So no matter where we are, or where we look, at some scale everything will look the same. From this foundational idea we can break into more cosmology, something about dark matter and black holes and a time-traveling twin, but it’s more fun to do what cosmologists known to do best- to look backwards!
In 1543, Copernicus realized that the Earth was not the center of the solar system, and that actually the Earth orbits the sun (not the other way around). The Copernican principle is the notion that the Earth is not the fixed center of creation. While the copernican principle may not bear the same teeth as the cosmological principle, it’s got the same clenching jaws. In 1543, humankind began to face an ugly truth: We are not special.
Feral in the barrel 