answer:Well, we’re not ”...sized precisely in the middle of all known physical phenomenon.” If one considers a Planck length as equal to zero, and The Universe as finite at any given moment, then precisely in the middle would be ½ the the distance across the universe. Also, the Universe is continually expanding, but the size of a brain cell is fairly constant, which means that the ratio of Planck Length:breadth of a brain cell may have been equal to brain cell:breadth of Universe at some point, but no longer. But that is a great video to explain the concept of Orders of Magnitude.