The well-known fact that magnetism is a relativistic effect is emphasized much too weakly in contemporary physics education and literature. By relativistic effect we mean motional consequence, i.e. the fact that a phenomenon appearance depends on the relative motion between observer and event. The magnetic force is a motional consequence of the electric force and can be derived from electrostatics by using relativistic transformation rules. In this way the two forces are unified into one basic dynamics, the electrodynamics.

In this paper we consider the reverse procedure, i.e. we derive some relativistic results from magnetism. We will base our discussion on the simplest possible phenomena: the pairwise interaction between two electric charges in rest and in uniform motion. By utilizing the classical electric and magnetic force laws, we will in particular derive time dilation. The main pedagogical advantage with our approach is that everything is based on simple observations which everyone can experience. The notion that relativistic effects are some kind of exotic phenomena with no importance for our daily life is a severe myth which we revise.

Starting with a conceptual discussion aiming at reaching qualitative conclusions, the ideas are then quantified by deriving time dilation and finally an overview of the literature is given.

Since our aim is to deal with concrete observable facts only, our consideration is free from force fields and accordingly the concept of light.