lation of the

contents.

According to the argument carried on in this and the Recapitu five preceding chapters, it is evident that certainty exists section's and can be justified to reason, while it is no less clear that absolute scepticism is not only irrational but self-contradictory. Since everything cannot be proved, while yet some things are absolutely certain, it is manifest that there must be truths which are self-evident and need no proof, to believe which is the very reverse of blind belief, since they are believed on the best evidence, namely, self-evidence, than which no other or better test is even conceivably possible for us. At the root of all certainty lie three orders of truths supremely certain and self-evident-an order of facts, an order of principles, and an order of inferences. The primary fact is that of our own self-knowledge. We have direct knowledge of our own being in its activity, whence, by a reflex act, we may observe either our feelings or our continued existence, and we may become as clearly and certainly aware of one of these as of the other. The second fact is that of the trustworthiness of the faculty of memory, the denial of which would involve us in absolute scepticism, while its recognition shows us we can know objective truth-namely, our own past. Amongst absolutely certain general principles, the most fundamental is the law of contradiction-a law so fundamental that it is impossible for any one really to deny it without thereby also asserting it. Geometrical axioms and the law of causation are also truths which are absolute and self-evident. That we should know the self-evidence of these things is wonderful, but not more wonderful than is every kind of knowledge. There are valid and absolutely certain processes of inference which make latent truths manifest. It is plain that if we would reason, or even think correctly, we must accept the practical adequacy of speech to convey thought, and the validity of inferences logically made. We must also admit the value, under the requisite conditions, of human testimony, and recognize the respect due to the common-sense judgments of mankind in ordinary, practical matters of everyday life, about which they may afford grounds for complete certainty when submitted to various necessary, but easy and obvious tests.

CHAPTER VII.

IDEALISM AND REALISM.

Explanation of these systems.

Need of studying “idealism”—What idealism is-Its attractiveness — “Realism”—Method of procedure.

idealism.

A DOUBT as to the real existence of the world about us Need of must seem almost as startlingly unreasonable to him who studying hears of it for the first time, as the before considered doubt respecting our knowledge of our own existence. That the mountains and rivers of the earth, the plants which clothe its surface, its varied animal population, the busy, teeming world of human life and our own very bodies, the showers and breezes which refresh, the tempests which destroy, and the sun, moon, and stars which variously illumine, all have a real existence in themselves, independently of a mind observing them, seems at first a matter too certain and obvious to admit of a moment's dispute; so that any one who professes to disbelieve it, must be like a man who believes his limbs are made of glass, and more or less of a lunatic. Yet illustrious men of a very high order of intellect, some of them distinguished philosophers and others masters in physical science, have not only professed to doubt this, but have even positively denied either that any independent world exists at all, or that its existence can, by any possibility, be known to us. These leaders of thought have also had a multitude of disciples and followers, and however much masters or pupils may have disagreed in the details of their several views, yet all have had this in common-that they have followed what is called "the