Observer
The concept of objective movement, independent of the changes in the quality of any Individual Existence (individual, living creature) makes the physical view independent of the concept of subjectivity, of some “I” of the observer, which is conceptually eliminated in the border.
The introduction of an observer in the theory of relativity does not change anything in essence: the observer remains a measuring device rather than a real Individual Existence with mental states.
The concept of extension in motion is joined by the so far little sublime concept of force as the cause of motion, which is very close to the outlook on life.