20. That the separate philosophical ideas are not anything optional or autonomously evolving, but grow up in connection and relationship with each other, that, however suddenly and arbitrarily they seem to appear in the history of thought, they nevertheless belong just as much to a system as the collective members of the fauna of a Continent—is betrayed in the end by the circumstance: how unfailingly the most diverse philosophers always fill in again a definite fundamental scheme of POSSIBLE philosophies. Under an invisible spell, they always revolve once more in the same orbit, however independent of each other they may feel themselves with their critical or systematic wills, something within them leads them, something impels them in definite order the one after the other—to wit, the innate methodology and relationship of their ideas.