We will now pursue a path similar to that followed in the first chapter, and see what more we can learn of the nature of Mind. We will endeavor to learn more definitely what constitutes its _a priori_ activity, in order, as there indicated, to achieve our object. Thus our present search is after the “Categories” and their significance. Taking the word category here in the sense of “a priori determination of thought,” the first question is: “Do any categories exist? Are there any thoughts which belong to the nature of mind itself?” It is the same question that Locke discusses under the head of “Innate ideas.” I. “Every act of knowing or cognizing is the translating of an unknown somewhat into a known, as a scholar translates a new language into his own.” If he did not already understand one language, he could never translate the new one. In the act of knowing, the object becomes known in so far as I am able to recognise predicates as belonging to it. “This is _red_;” unless I know already what “red” means, I do not cognize the object by predicating _red_ of it. “Red is a color;” unless I know what “color” means, I have not said anything intelligible—I have not expressed an act of cognition. The object becomes known to us in so far as we recognize its predicates—and hence we could never know anything unless we had at least one predicate or conception with which to commence. If we have one predicate through which we cognize some object, that act of cognition gives us a new predicate; for it has dissolved or “translated” a somewhat, that before was unknown, into a known; the “not-me” has, to that extent, become the “me.” Without any predicates to begin with, all objects would remain forever outside of our consciousness. Even consciousness itself would be impossible, for the very act of self-cognition implies that the predicate “myself” is well known. It is an act of identification: “I am myself;” the subject is, as predicate, completely known or dissolved back into the subject. I cognize myself as myself; there is no alien element left standing over against me. Thus we are able to say that there must be an a priori category in order to render possible any act of knowing whatever. Moreover, we see that this category must be identical with the _Ego_ itself, for the reason that the process of cognition is at the same time a recognition; it predicates only what it recognizes. Thus, fundamentally, in knowing, Reason knows itself. Self-consciousness is the basis of knowledge. This will throw light on the first chapter; but let us first confirm this position by a psychological analysis. II.