the form of memory; the future is not a predetermined order which only a natural disability prevents us from knowing, it is yet uncreated; conscious life is the enduring present which grows with the past and makes the future.

This reality of consciousness is our continually changing experience. But there is also another reality with which it seems to be in necessary relation and also in complete contrast—this is the reality of the material or physical universe. The world of physical reality seems to be composed of a matter that cannot change in a space that is absolutely unchangeable. This physical world seems made up of solid things, formed out of matter. Change in physical science is only a rearrangement of matter or an alteration of position in space.

This physical reality is not, as psychical reality is, known to us directly; it is an interpretation of our sense experience. Immediate experience has objects, generally called sense data. These objects are what we actually see in sensations of sight, what we actually hear in sensations of sound, and so on; and they lead us to suppose or infer physical objects—that is, objects that do not depend upon our experience for their existence, but whose existence is the cause of our having the experience. The process by which we infer the nature of the external world from our felt experience is logical. It includes perceiving, conceiving, thinking or reasoning. The object of the logical process, the aim or ideal to which it seeks to attain, is truth. Knowledge of reality is truth.

There are therefore two realities, the reality of our felt experience from which all thinking sets out, and the reality which in thinking we seek to know. The one reality is immediate; it is conscious experience itself. The other reality is that which we infer from the fact of experience, that by which we seek to explain our existence. The one we feel, the other we think. If the difference between immediate knowledge and mediate knowledge or inference lay in the feeling of certainty alone or in the nature of belief, the distinction would not be the difficult one that it is. The theories of idealism and realism show how widely philosophers are divided on the subject. We are quite as certain of some of the things that we can only infer as we are of the things of which we are immediately aware. Wd cannot doubt, for instance, that there are other persons besides ourselves, yet we can have no distinct knowledge of any consciousness but one—our own. Our knowledge that there are other minds is an inference from our observation of the behaviour of some of the things we directly experience, and from the experience of our own consciousness. And even those things which seem in direct relation to us—the things we see, or hear, or touch—are immediately present in only a very small, perhaps an infinitesimal, part of what we know and think of as their full reality; all but this small part is inferred. From a momentary sensation of sight, or sound, or touch we infer reality that far exceeds anything actually given to us by the sensation.

Thinking is questioning experience. When our attention is suddenly attracted by something—a flash of light, or a sound, or a twinge of pain—consciously or unconsciously we say to ourself, What is that? The that—a simple felt experience—contains a meaning, brings a message, and we ask what? We distinguish the existence as an appearance, and we seek to know the reality. The quest of the reality which is made known to us by the appearance is the logical process of thought. The end or purpose of this logical process is to replace the immediate reality of the felt experience with a mediated-reality—that is, a reality made known to us. Directly, therefore, that we begin to think, the immediately present existence becomes an appearance, and throughout the development of our thought it is taken to be something that requires explanation. We seek to discover the reality which will explain it.

It is in this distinction of appearance and reality that the problem of truth arises. It does not depend upon any particular theory of knowledge. The same fact is recognised by idealists and by realists. Idealism may deny that the knowledge of independent reality is possible; realism may insist that it is implied in the very fact of consciousness itself—whichever is right, the reality which thinking brings before the mind is quite unlike and of a different order to that which we immediately experience in feeling. And even if we know nothing of philosophy, if we are ignorant of all theories of knowledge and think of the nature of knowledge simply from the standpoint of the natural man, the fact is essentially the same—the true reality of things is something concealed from outward view, something to be found out by science or by practical wisdom. Our knowledge of this reality may be true, in this case only is it knowledge; or it may be false, in which case it is not knowledge but opinion or error.

The reality then, the knowledge of which is truth, is not the immediate reality of feeling but the inferred reality of thought. To have any intelligible meaning, the affirmation that knowledge is true supposes that there already exists a distinction between knowledge and the reality known, between the being and the knowing of that which is known. In immediate knowledge, in actual conscious felt experience there is no such distinction, and therefore to affirm truth or error of such knowledge is unmeaning. I cannot have a toothache without knowing that I have it. In the actual felt toothache knowing and being are not only inseparable—they are indistinguishable. If, however, I think of my toothache as part of an independent order of reality, my knowledge of it may be true or false. I am then thinking of it as the effect of an exposed nerve, or of an abscess or of an inflammation—as something, that is to say, that is conditioned independently of my consciousness and that will cease to exist when the conditions are altered. In the same way, when I behold a landscape, the blue expanse of sky and variegated colour of the land which I actually experience are not either true or false, they are immediate experience in which knowing is being and being is knowing. Truth and error only apply to the interpretation of that experience, to the independent reality that I infer from it. We can, then, distinguish two kinds of knowledge which we may call immediate and mediate, or, better still, acquaintance and description. Accordingly, when we say that something is, or when we say of anything that it if real, we may mean either of two things. We may mean that it is part of the changing existence that we actually feel and that we call consciousness or life, or we may mean that it is part of an independent order of things whose existence we think about in order to explain, not what our feeling is (there can be no explanation of this), but how it comes to exist. We know by description a vast number of things with which we never can be actually acquainted. Such, indeed, is the case with all the knowledge by which we rule our lives and conceive the reality which environs us. Yet we are absolutely dependent on the reality we know by acquaintance for all our knowledge of these things. Not only is immediate sense experience and the knowledge it gives us by acquaintance the only evidence we have of the greater and wider reality, but we are dependent on it for the terms wherewith to describe it, for the form in which to present it, for the matter with which to compose it. And this is the real ground of the study of philosophy, the justification of its standpoint. It is this fact—this ultimate undeniable fact—that all reality of whatever kind and in whatever way known, whether by thought or by feeling, whether it is perceived or conceived, remembered or