6. For even where at first sight you might think it most out of place, I mean in relation to that kind of truth whose primary evidence is the consciousness of the individual, so that the competent witness of truth is necessarily but one person, there is oneness of opinion, there is unanimity, and the testimony of the one competent witness is not contradicted or doubted by that of any other presumably competent. When, for instance, I am conscious of the sensation of seeing an inkstand before me, no one seeing reason to doubt my assertion to that effect, all presumably competent testimony on the subject must needs be concentrated in myself; and the fact of my seeing an inkstand, though for my own conviction verified in a way independent of any such argument, is, for the conviction of others, only pronounceable as true, because all presumably competent authority is of one mind in alleging its truth. In thus far exemplifying the use of this principle, I have exhibited it in the exercise of its primary office only, which, however, is not that which, on behalf of philosophy, I am here demanding from it. I have shown it, namely, as used by the public to establish truth positively, and not in the way wherein it may be used to distinguish truth comparatively. But it is solely in this latter office that it becomes a criterion of truth, an arbiter between the true and the false, an indicator of both, and more especially of what has the character of ascertained truth, and what has not; and this, it will be remembered, was the office I sought from it, and constituted the ultimate purpose of my taking up the consideration of the subject. Having with as much brevity as just suffices for that purpose, explained the nature of the principle in question, and its use by society at large, it now only remains that I should explain that purpose itself, by theory and example. What I am doing in tracing the unanimity principle from its first instinctive use by the public to its secondary and meditated one by philosophy, is a purely critical act, comparable to that of the rhetorician who appreciates the character of certain modes of thinking which have long since been practised by mankind, and shows what therein is approvable--all the rest being liable to censure.