 The conclusion is that in quantum mechanics we are confronted with a complementarity between two descriptions which are united in the classical mode of description: the space-time description (or coordination) of a process and the description based on the applicability of the dynamical conservation laws. The quantum forces us to give up the classical mode of description (also called the “causal” mode of description by  Bohr[4]:  it is impossible to form a classical picture of what is going on when radiation interacts with matter as, e.g., in the Compton effect.