There are two main approaches to both philosophy, mathematics and physics (and other areas):
Constructivism - intuitionism - realism:
- existence of real world independent of human hand and mind (stars, dinosaurs)
- existence of real world constructed by human hand and mind (cars, computers)
- existence of image of real world created by human hand and mind (math models, computer programs).
- existence of sign - image created by human hand and mind (math models)
- relation between sign - image and (real) world magical.
Being an extreme formalist, Einstein developed both the special and general theory of relativity in a mission to bring order into the mess of relative coordinate systems by forming a universal standard forcing all observers using different coordinate systems to agree. The Lorentz transformation as foundation of the special theory, is thus a dictate to be followed when making observations using different inertial coordinate systems. Many Worlds - One Observer.
Einstein's principle of relativity is an ultimate expression of formalism:
- The equations describing the laws of physics are to have the same form in all admissible frames of reference.
For a constructivist, Einstein's dictated unification program would serve no purpose. Different people would be allowed to construct different images and have different gods and only a minimal coordination based on practical needs, would be called for, like a system of different floating currencies. The real World would be One, but there would be many different views depending on observer position. One World - Many Observers.
In this sense a constructivist is a true relativist, or democrat, while Einstein's relativity theory would rather reflect the opposite of absolutism (Ein Volk, ein Reich, ein Fuhrer). This aspect is developed in more detail in Many-Minds Relativity.
For a constructivist, the choice of coordinate system is a matter of convenience and does not hide any secrets of physics. For a formalist like Einstein, coordination of observations in different coordinate systems is of paramount importance with the goal of defining a universal standard, and the physisc is secondary if not nil.