Adolf von Harnack was the first president of the Kaiser Wilhelm Society, the predecessor of the Max Planck Society. In 1928 he described its method. The director is so much the central figure, he said, “that one can also say: the society chooses a director and builds an institute around him.” The Max Planck Society took over this Harnack-Prinzip at its founding in 1948. Today the Max Planck Institute for Chemistry calls the principle outdated in this form, because institutes are almost never founded around a single researcher anymore. The principle still applies when the society selects its researchers.