Wandering in quantum researches should lead to the rational goal - understanding. All history of the science shows how meaningful mathematical laws in physics, engineering, chemistry, etc., arose on the ground of rational human practice. I would like show that in the contradictory development of quantum physics, the theory ultimately follows the same line. ``Elementary" particles do exist. This fact does not depend on the procedure of a measurement. The existence, however, requires some description that mostly based on relations between measurable values. Our goal is to bridge this objective reality and its mental reflection. It is assumed that existence should be based on the invariant relations between measurable values. What kind of the invariance should be used?
Peter Leifer