Fichte has called his system a _Wissenschaftslehre_—a theory of knowledge. Modern German used the word _Wissenschaft_, as modern English uses the word Science, to denote the certified knowledge of piecemeal fact, the partial unification of elements still kept asunder. But by _Wissen_, as opposed to _Erkennen_, is meant the I know, am aware and sure, am in contact with reality, as opposed to the derivative and conditional reference of something to something else which explains it. The former is a wider term: it denotes all consciousness of objective truth, the certainty which claims to be necessary and universal, which pledges its whole self for its assertion. Fichte thus unifies and accentuates the common element in the Kantian criticisms. In the first of these Kant had begun by explaining the nature and limitation of empirical science. It was essentially conditioned by the given sensation—dependent i.e. on an unexplained and preliminary element. This is what makes it science in the strict or narrow sense of the term: its being set, as it were, in the unknown, the felt, the sense-datum. The side of reality is thus the side of limitation and of presupposition. But what makes it truth and knowledge in general, on the other hand,—as distinct from _a_ truth (i.e. partial truth) and a knowledge,—is the ideal element—the mathematical, the logical, the rational law,—or in one word, the universal and formal character. So too every real action is on one hand the product of an impulse, a dark, merely given, immediate tendency to be, and without that would be nothing: but on the other hand it is only an intelligent and moral action in so far as it has its constitution from an intelligence, a formal system, which determine its place and function. It is on the latter or ideal element that Kant makes the emphasis increasingly turn. Not truths, duties, beauties, but truth, duty, beauty, form his theme. The formal element—the logical or epistemological condition of knowledge and morality and of beauty—is what he (and still more Fichte) considers the prime question of fundamental philosophy. His philosophy is an attempt to get at the organism of our fundamental belief—the construction, from the very base, of our conception of reality, of our primary certainty. In technical language, he describes our essential nature as a Subject-object. It is the unity of an I am which is also I know that I am: an I will which is also I am conscious of my will(49). Here there is a radical disunion and a supersession of that disunion. Action and contemplation are continually outrunning each other. The I will rests upon one I know, and works up to another: the I know reflects upon an I will, and includes it as an element in its idea.