Jacobi has stated this charge most distinctly in the seventh supplement to his Letters on Spinoza,--borrowing his line of argument from the works of Spinoza himself, and applying it as a weapon against knowledge in general. In his attack knowledge is taken to mean knowledge of the finite only, a process of thought from one condition in a series to another, each of which is at once conditioning and conditioned. According to such a view, to explain and to get the notion of anything, is the same as to show it to be derived from something else. Whatever such knowledge embraces, consequently, is partial, dependent and finite, while the infinite or true, _i.e._ God, lies outside of the mechanical inter-connexion to which knowledge is said to be confined.--It is important to observe that, while Kant makes the finite nature of the Categories consist mainly in the formal circumstance that they are subjective, Jacobi discusses the Categories in their own proper character, and pronounces them to be in their very import finite. What Jacobi chiefly had before his eyes, when he thus described science, was the brilliant successes of the physical or 'exact' sciences in ascertaining natural forces and laws. It is certainly not on the finite ground occupied by these sciences that we can expect to meet the in-dwelling presence of the infinite. Lalande was right when he said he had swept the whole heaven with his glass, and seen no God. (See note to § 60.) In the field of physical science, the universal, which is the final result of analysis, is only the indeterminate aggregate,--of the external finite,--in one word, Matter: and Jacobi well perceived that there was no other issue obtainable in the way of a mere advance from one explanatory clause or law to another. 63.] All the while the doctrine that truth exists for the mind was so strongly maintained by Jacobi, that Reason alone is declared to be that by which man lives. This Reason is the knowledge of God. But, seeing that derivative knowledge is restricted to the compass of finite facts, Reason is knowledge underivative, or Faith.