But if the nomenclature adopted by Locke be the right one, there ought to be a change in these current modes of speaking and writing. One who should reject the proofs of Euclid, would be unreasonable; one who should maintain that Thurtel or Greenacre were innocent of murder, would be unreasonable; but, one who should deny the truth of any self-evident proposition, would not be unreasonable; for to say this, would be to say that reason has cognisance of such propositions, whereas, according to him, it is expressly not reason, but intuition that takes this office. The words "intuitional" and "unintuitional," must be invented to supply the obvious need which the apparent gap discovers; there seems no other way of supplying it. Lest I should be suspected of somewhat making up a case; of having, perhaps, represented not so much what Locke really means, as what he seems to mean, I will remind the reader that Locke is undertaking the formal definition of a word, and that on such a critical occasion, it is proper to give him credit for not meaning otherwise than he seems to mean. The passage which is my text, will be found in the earlier part of the seventeenth chapter of the fourth book. Indeed, I could at once prove my indictment by citing a few words from it, accompanied by a comment of my own, had I any right to impose on the reader a belief in the discriminating fairness and matter-of-fact accuracy, both of my extracts and my comment. I will, however, venture on such a step; I will suppose myself commenting on this passage, and proceed thus: Locke, it will be seen in this, his foremost and professed definition of the word reason, contrasts it with "sense and intuition." Whether he holds these to be identical with what he calls "the outward and the inward sense," is not quite clear. That, however, is not the question. He says, that these two faculties "reach but a very little way"; for that "the greatest part of our knowledge depends upon deductions and intermediate ideas." Now, reason, he says, may be defined to be that faculty, whose specific office it is "to find out and apply" those intermediate ideas and deductions by which we obtain knowledge that consists of two kinds, one that which exalts us into "certainty," the other that which, though less generous diet for the mind, we have constantly good ground for gladly acquiescing in, and which we call "probability." So that, says Locke, if you ask, "What room is there for the exercise of any other faculty but outward sense and inward perception?" I can abundantly reply, "Very much." I have shown you that without this "demonstrative" faculty, our knowledge would be but a skeleton; it would, indeed, not be properly speaking knowledge, but mere rudiments of knowledge.