نظرية المعرفة (ed. 2)

No proposition is possible without content or without form. It must contain something whereof we know, and something which is known thereof. Hence, the first principle of the science of knowledge must have both content and form. Now, this first principle is to be immediately and of itself certain, and this can only signify: its content must determine its form, and its form its content. Its form can only fit its content, and its content can only fit its form; every other form connected with that content, or every other content connected with that form, would cancel that principle itself, and thus annihilate all knowledge. Hence, the form of the absolute first principle of the science of knowledge is not only contained in that principle itself, but is also presented as absolutely valid for the content of that principle. Again: if there should be, besides this absolute first principle, still other fundamental principles of the science of knowledge—which in that case can only be partly absolute, and must be partly derived from the first principle, since otherwise in the first case they would not be fundamental principles, and in the latter case not connected with the first and highest principle—then the absolute part of these other fundamental principles could only be either the content or the form; and, likewise, the conditioned or derived part of these principles could only be either the content or the form. If the content of these other fundamental principles be their absolute or unconditioned part, then the absolute first principle of the science of knowledge must condition the form of those contents; or if the form of those other principles be the unconditioned part, then their content must be conditioned by the first principle of the science of knowledge; and thus indirectly also their form, that is, in so far as the form is to be form of the content.…