are certain; but from what does their own certainty follow?
And even after we shall have satisfactorily answered this question, does not a new and quite different one threaten us? We are going to draw our conclusions thus: If the fundamental principle is certain, then another proposition also is certain. How do we get at this then? What is the ground of the necessary connection between the two, whereby the one is to have the same certainty which belongs to the other? What are the conditions of this connection, and whence do we know that they are the conditions and the exclusive conditions and the only conditions of this connection? And how do we get at all to assume a necessary connection between different propositions, and exclusive but exhausted conditions of this connection?
In short, how shall the absolute certainty of the fundamental principle, and how shall the authority to draw from it conclusions as to the certainty of other propositions, be demonstrated? That which the fundamental principle is to have itself and to communicate to all other propositions which occur in the science, I call the inner content of the fundamental principle and of science generally; the manner in which it communicates this certainty to other propositions I call the form of science. The question is, therefore, How are form and content of a science possible? or how is science itself possible?
That which would give an answer to this ques-
