Just as a piece of oak wood has the twofold quality of partaking not alone, with its oaken nature, of the general nature of wood, but also of the unlimited generality of all nature, so is the intellect a limited specialty, which has the quality of being universal as a part of the universe and of being conscious of its own and of all universality. The boundless universal cosmic nature is embodied in the intellect, in the animal as well as in man, the same as it is embodied in the oak wood, in all other wood, in all matter and force. The worldly monistic nature which is mortal and immortal, limited and unlimited, special and general, all in one, is found in everything, and everything is found in nature--understanding or the power of knowledge is no exception. It is this twofold nature of the universe, this being at the same time limited and unlimited, this reflection of its eternal essence and eternal truth in changing phenomena, which has rendered its understanding very difficult for the human mind. This intricate quality has been represented by religion in the fantastic picture of two worlds, separating the temporal from the eternal, the limited from the unlimited, too unreasonably far. But nowadays the indestructibility of matter and the eternity of material forces is a matter of fact accepted by natural science. The positive outcome of philosophy, then, is the knowledge of the monistic way in which the seeming duality of the universe is active in the human understanding. III AS TO HOW THE INTELLECT IS LIMITED AND UNLIMITED Understanding taught by experience no longer muses about universal nature, but acquires a knowledge of it by special studies. By degrees philosophy, first unconsciously and lately clearly and plainly, has taken up the problem of ascertaining the limits of understanding. This philosophical problem first assumed the form of polemics. It became opposed to the religious dogma which represented the human mind as a small, subservient, limited and restricted emanation of the unlimited divine spirit. This terrestrial emanation was regarded as too limited to understand and find its divine source. The study of the limits of the understanding has now emancipated itself from this dogma, but not to such an extent that there is no longer any mysterious obscurity floating around the understanding and intelligence, and especially around the question whether the human mind can penetrate only into some things while others will remain in the unscrutable darkness of faith and intuition, or whether it may penetrate boldly and without hindrance into the infinity of the physical and chemical universe.