Three different approaches to the same interaction: the Yukawa model in nuclear physics

17 pages, 9 figures. Dedicated to Professor Henryk Witala at the occasion of his 60th birthday. Submitted in Few-Body SystemsAfter a brief discussion of the meaning of the potential in quantum mechanics, we examine the results of the Yukawa model (scalar meson exchange) for the nucleon-nucleon interaction in three different dynamical frameworks: the non-relativistic dynamics of the Schrodinger equation, the relativistic quantum mechanics of the Bethe-Salpeter and Light-Front equations and the lattice solution of the Quantum Field Theory, obtained in the quenched approximation