I was a bit surprised at first but indeed, I realize that it is nice to get a feeling for the principle and its consequences first, to develop an intuitive understanding of the theory (particularly its differences with the “everyday” Galilean model) before delving into the mathematical derivation of it. And thanks again for this great course; the content, the pace, the exercices and simulation tools are absolutely top-notch. I can’t believe we have access to it for free. Thanks a million!