This is an overview of the dilogic diagram regarding the interpretations of quantum physical phenomena. The "two-slit experiment" is often mentioned as an example of a quantum physics experiment, in which the result (a wave-like diffraction pattern) is found if particles pass through two slits, but a scattering of points pattern is found if the particles are measured one at a time. In other words, the result depends on what experimental setup is chosen by the experimenter. Why is this?
The exaggerations were proposed first, as follows:
(Exaggerated) Completeness: The "collapse of the Schroedinger wave function" results in many possibilities occurring in reality. There is no need within the theory to distinguish one branch of the split from another. Problem: this implies that a tremendous number of new worlds is being produced every moment all over the universe. This violates parsimony ("Occam's razor") which is to be expected for a good theory.
(Exaggerated) Appearances: The choice of the experimenter changes what the experimenter observes, because it changes the world in accordance with the experimenter's choice. Problem: what precisely is meant by this "choice" of an "experimenter"? What is the equation for that? According to Feynman's "operationalist" description, we know nothing except the results shown by the measuring instruments.