which he at first gave of the science, rarely corresponds with his idea; for this idea lies, like a germ, in our reason, its parts undeveloped and hid even from microscopical observation. For this reason, we ought to explain and define sciences, not according to the description which the originator gives of them, but according to the idea which we find based in reason itself, and which is suggested by the natural unity of the parts of the science already accumulated. For it will of ten be found that the originator of a science and even his latest successors remain attached to an erroneous idea, which they cannot render clear to themselves, and that they thus fail in determining the true content, the articulation or systematic unity, and the limits of their science.
It is unfortunate that, only after having occupied ourselves for a long time in the collection of materials, under the guidance of an idea which lies undeveloped in the mind, but not according to any definite plan of arrangement—nay, only after we have spent much time and labour in the technical disposition of our materials, does it become possible to view the idea of a science in a clear light, and to project, according to architectonical principles, a plan of the whole, in accordance with the aims of reason. Systems seem, like certain worms, to be formed by a kind of generatio aequivoca—by the mere confluence of conceptions, and to gain completeness only with the progress of time. But the schema or germ of all lies in reason; and thus is not only every system organized according to its own idea, but all are united into one grand system of human knowledge, of which they form members. For this reason, it is possible to frame an architectonic of all human cognition, the formation of which, at the present time, considering the immense materials collected or to be found in the ruins of old systems, would not indeed be very difficult. Our purpose at present is merely to sketch the plan of the architectonic of all cognition given by pure reason; and we begin from the point where the main root of human knowledge divides into two, one of which is reason. By reason I understand here the whole higher faculty of cognition, the rational being placed in contradistinction to the empirical.
If I make complete abstraction of the content of cognition, objectively considered, all cognition is, from a subjective point of view, either historical or rational. Historical cognition is
