line of flow (along the dotted line in the plan), we shall have that which is represented in Fig. 3. Here we do not

psychical wave. In Fig. 3 the word "clear" occupies, as before, the summit of the wave. But our eye is also being affected by the lines above and below, and by the rest of the page. We do not generally notice this, because it is of no practical importance in everyday life. For us, as students of psychology, it is important. We must clearly grasp the fact that in any moment of consciousness, there are in addition to and alongside the dominant elements constituting the summit of full clear consciousness, dimly felt elements which may have little or no direct connection with those dominant elements. These we will speak of as subconscious; and I beg the reader to satisfy himself in his own experience of the reality of the existence of these subconscious elements. As I write, I am dimly aware of the ticking of the clock, of the plash of rain against the window, of the position of my body, of the pressure of my clothes, of the scent and taste of a cigarette, of an incipient headache, and of much besides. All these are merely subconscious, and subconscious in different degrees.

As the validity of many of the arguments in this book depend upon the real existence of subconscious elements in

the psychical wave, I will further illustrate my meaning in another way and in other phraseology, which, together with that of "the wave of consciousness," I shall have frequent occasion to employ. My further illustration is that from vision,-in most of us the dominant sense. If we fix our eyes on any distant object, such as a church spire or clump of trees, this is in the focus of vision; but it is set in the midst of a wide visual field. The focus shades off into and is surrounded by a margin, in which the objects, instead of being clear-cut and well-defined, like the church spire or the clump of trees, are dim and blurred in outline. The focus here answers to the summit or crest of the psychical wave; the margin to its subconscious body, comprising all the rest of the wave other than the crest. Now, although this illustration is based on vision, it is applicable to consciousness generally. Those who have an ear for, and some little knowledge of, music, can, when they are listening to a fourpart song, focus their attention on the treble, alto, tenor, or bass, making that the dominant theme, and allowing the other parts to be marginal. For the ordinary listener, the air is focal, the other parts marginal. Music, which so often gives us a leading theme, vocal or other, and its setting or accompaniment, affords indeed an excellent illustration of what I am seeking to enforce,-that in addition to what is focal in consciousness (the theme) there is much that is subconscious or marginal (the accompaniment). And this I repeat is true not only of vision or of hearing, but of consciousness in general. I take a walk in the country with a friend, and we are discussing the relation of music to poetry. This is our theme; it is focal to our consciousness; the points in the discussion as they arise successively Occupy the crest of the psychical wave. But there is plenty of accompaniment; there is much body to the wave. A thousand sights, scents, sounds, all breathing the life of spring; the soft yet invigorating air; the tingling of the

Α

muscles to the exercise,-all these form a delightful setting to the theme, a margin to the focus, a body to the wave of consciousness. And any one of these subconscious elements may by increased intensity rise at any moment into dominance, and occupy the crest of the wave or the focus of consciousness. My friend, for example, who is a keen naturalist, stops in the middle of his sentence to point out some rare bird which has caught his attention. Often when one is reading or listening to a discourse, there is an undercurrent of subconsciousness, wholly unconnected with the subject of the book or the lecture; presently this may rise unbidden, and monopolise the wave crest; and one finds that the words over which the eye has been travelling, or which have been falling upon the ear, have suggested nothing definite and rememberable. They have merely entered the margin of consciousness, the focus being other wise occupied.

In riding a bicycle slight movements of the handle are constantly necessary. But the skilful rider spinning along a good road guides the machine automatically or unconsciously, as we are wont to say,—subconsciously, as we should more correctly say. In all matters of skill, when it is wellestablished, the mere carrying out of the skilled action is marginal and subconscious, focal consciousness being concentrated on the end to be attained, or on some particular factor in the process. The swordsman who had to focus his attention on, and exercise fully conscious control over each several parry, would soon succumb to his better trained antagonist in whom all this is a matter of organised habit carried out subconsciously. His attention is focussed on his adversary's sword-point. I would ask the reader, who is a billiard-player, or cricketer, or a player of lawn-tennis-in fact of any game requiring skill-to exercise a little selfobservation in the matter. He will, if I mistake not, be able to verify the truth of my assertion, that his focal conscious

ness is constantly fixed on some salient point of the skilled action, while the application of the skill to that salient and focal point is marginal; and, further, that this marginal exercise of the skill is not really unconscious, but is subconscious. He who kicks a goal at football rivets his attention on striking the ball precisely there and thus; all the rest is marginal to his consciousness.

Note then the complexity of the wave of consciousness. We are too apt in psychology to pay attention solely to focal consciousness, omitting all reference to the great body of marginal subconsciousness. But this is a great mistake. The focal consciousness very often is what it is in virtue of the subconscious margin in which it is set. The dawning elements of the psychical wave, the waning elements, and all the marginal elements, form parts of any present state of consciousness, and are more or less instrumental in determining its nature. I shall employ the phrase "state of consciousness" to describe all that is comprised in the psychical wave in any moment of consciousness. This embraces not only the focal constituent, but a greater or less number of marginal constituents, which form the peculiar setting of the focus in the moment of consciousness in question. At different times in the same individual, and presumably in different individuals, the states of consciousness whose succession constitutes the onwardflowing wave, vary considerably in complexity and in intensity. In moments of quiet concentrated thought the states of consciousness are relatively homogeneous and simple. In moments of distraction and of bustling excitement they are heterogeneous and complex. When we languidly let our thoughts wander hither and thither without aim or purpose, the states of consciousness are of low intensity; but in moments of keen excitement, of breathless interest, or of strenuous thought, the intensity is much increased. In the psychical wave, intensity may be represented

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by the height of the wave-crest above the base line which is termed the "threshold of consciousness.;" complexity, by its width, or the number of constituent elements in the state of consciousness embraced by the wave.

And

The phraseology in which I have endeavoured to express some of the observable facts of consciousness, is based on that method of diagrammatic or graphic representation which has been found of conspicuous assistance wherever it has been employed; I mean the use of curves. now we may proceed to give to our curve its simplest geometrical expression. In Fig. 4, the horizontal line represents the threshold of consciousness, the vertical line a scale by which the intensity of focal or marginal elements in

consciousness may be measured. The several elements which go to the composition of a state of consciousness are thus spread out along the curve in order of their intensity, from the focal constituents of maximum intensity to the