This opinion, however, can be sustained neither in its principle nor in its historical application. It is defective in its principle, because in history freedom and necessity interpenetrate, and, therefore, while we find, if we consider it in its general aspects, a rational connection running through the whole, we also see, if we look solely at its individual parts, only a play of numberless contingencies, just as the kingdom of nature, taken as a whole, reveals a rational plan in its successions, but viewed only in its parts, mocks at every attempt to reduce them to a preconceived plan. In history we have to do with free subjectivities, with individuals capable of originating actions, and have, therefore, a factor which does not admit of a previous calculation. For however accurately we may estimate the controlling conditions which may attach to an individual, from the general circumstances in which he may be placed, his age, his associations, his nationality, &c., a free will can never be calculated like a mathematical problem. History is no example for a strict arithmetical calculation. The history of philosophy, therefore, cannot admit of an apriori construction; the actual occurrences should not be joined together as illustrative of a preconceived plan; but the facts, so far as they can be admitted, after a critical sifting, should be received as such, and their rational connection be analytically determined. The speculative idea can only supply the law for the arrangement and scientific connection of that which may be historically furnished.