I think therefore I exist. If you try to measure yourself, you'll be your own reference point and that's a distance of zero cuils.
But our observations are impure. Our senses are not perfectly sharp, and we can make devices much sharper than our senses could ever be. So wouldn't the physical world be zero cuils? But we are able to sense enough to know that physically things are imperfect, and aren't always the perfect representation of what they should be. So that forces us to take a step deeper. I would put forth that the distance of zero cuil can only be measured on the cosmic mesh, in the distortions caused by time and mass.