The next general characteristic of dreams is that, though resembling waking experience in many respects, they seem never exactly to reproduce the order of this experience. Most of our dreams differ very widely from any events ever known to us in waking life, and even those which most closely resemble certain portions of this life introduce numerous changes in detail. These deviations involve one or two distinct elements. First of all, there is a great confusion of the order in time, space, <fcc∙, which holds among real objects and events. Widely remote places and events are brought together, persons set in new relations to one another, and so on. Secondly, the objects and scenes are apt to assume a greatly exaggerated intensity. They take a firmer hold of us, so to speak, than our waking experience. We may when awake think of dreams as unsubstantial and unreal, but to the dreamer at the moment his imagined surroundings are more real, more impressive, than the actual ones which he perceives when awake. Dream-fancy exaggerates the various aspects of objects, makes what is large still larger, what is striking still more striking, what is beautiful still more beautiful, and so ou.

Having touched on these approximately universal characteristics of dreams, we will now specify a few of the more variable features. For example, iu a large number of our dreams we appear to be passive spectators of events which we are incapable, or rather do not think, of controlling in any way. In other dreams, again, we seem to be lively actors in the scene,—talking, moviug, &c., as we are wont to do in waking life. In a class of dreams lying midway between these two extremes we appear to be impelled to act, to be struggling to seize some offered good or to avert some threatening evil, yet to be unable to execute our wishes. Once more, dreams differ very much as to their degree of reasonableness. It is certain that in many cases the dreamer is easily imposed on, sees no contradictions, does not seek to understand the events which unfold themselves before his fancy, and so on. In some instances, indeed, the mind of the dreamer loses even the sense of identity in objects, and metamorphizes persons in the most capricious manner; and this confusion of identity may embrace the dreamer himself, so that he imagines himself to be somebody else, or projects a part of himself, so to speak, into another personality, which thus becomes an alter ego and an object for the contemplation of the remaining self. Yet though it is true that many, probably a large proportion, of our dreams, are thus unintelligible to waking thought, there is a number of well authenticated dreams in which persons have proved themselves to be possessed not only of their ordinary, but even of an extraordinary, power of reflection. We refer to the well-known stories of the intellectual achievements of Condillac, Condorcet, Coleridge, &c., when dreaming. Once more, great differences are observable in dreams with respect to the feelings excited by the visionary experiences. Sometimes the circumstances in which we find ourselves affect us much as in waking life;—danger terrifies us, beauty delights us, and so on. At other times, however, we are not thus affected;—what would puzzle, confuse, or shock our miude in waking experience fails to do so in dream-life. Finally, there are certain exceptional features of dream-life, as a vague consciousness of dreaming, which assumes the form of a dream within a dream, and the repetition of the images of previous dreams with a recognition of the familiarity of the dream scenes. It need hardly be added that dreaming varies greatly, both in quantity and in quality, according to individual temperament, habits of thought, &c.

Theories of Dreaming.— From the slight sketch of the character of the dreaming process just given, it might be conjectured that the human mind at all times would be profoundly impressed with the fact of dreaming, and seek to arrive at some explanation of what on the surface is undoubtedly so mysterious and so wonderful a phenomenon. And as a matter of history we find that men have in all the known stages of their intellectual development endeavoured to account for the visions of the night. The various theories thus put forward fall into two main classes—the supernatural and the natural. By the former we mean all explanations which assume the action of forces unknown to our waking experience; by the latter those which make no such assumption, but seek to interpret dream-phenomena as products of forces familiar to waking perception. The supernatural hypothesis, again, falls into two divisions, according as the dream is regarded as the immediate effect of some reality corresponding to the actual world of our waking experience, or as it is conceived as a mediate result depending on the volition and command of some absent being. We thus have three main methods of explaining dreams :—(a) The naive objective explanation; (ό) the religious explanation ; (c) the scientific explanation.

(a) The Dream as Immediate Objective Experience.— According to recent researches the savage mind regards dreaming as no less real an objective experience than waking. The objects and scenes which flit before the dreaming fancy of the primitive man are real material existences, the sounds he seems to hear are real external sounds, the dream figures which stand before his imagination and converse with him are real persons. How then does he conceive the relation of this dream-world to the world of waking experience 1 This question has lately been answered by Mr E. B. Tylor and Mr Herbert Spencer. The belief in the objective reality of dreams requires the savage to conceive a double nature both for objects (animate and inanimate) external to himself and for himself. The vision of dead ancestors, of material objects long since lost or destroyed, easily suggests the idea of a duplicate of the original person of thing, a second self or soul. On the other hand, when the savage dreams that he goes forth to accustomed scenes, to hunt, to fight, and so on, he accounts for the dream by the supposition that his own second self or soul leaves the body and passes forth to the particular locality. Thus the dream-life shapes itself to our primitive philosopher as an intercourse of souls or duplicate selves, co-ordinate with, and of equal reality with, the experience of waking life. It appears to follow from the unfamiliarity of dream scenes, personages, &c., that the region visited during sleep will be projected by the savage mind quite outside the world of waking observation. Mr Spencer connects with this fact the earliest theories of another world or a spiritual state. (For a fuller account of the part played by dreams in primitive ideas consult E. B. Tylor, Primitive Culture, vol. i. chap. xi.; H. Spencer, Principles of Sociology, i. ch. x. et seg.)

(ό) The Dream as α Communication from α Supernatural Being.— It is plain that even in the savage’s conception of dreaming there is room for the thought of a divine announcement. When once the idea of superior beings, deities, demons, <fcc., is reached, it becomes natural to regard the visit of some departed soul as the despatch of a messenger to the dreamer. In this way the first mode of explanation passes insensibly into the second. In higher stages of religious thought the view of a dream as a divine revelation takes a less crude form. The immediate object present to the dreamer is no longer conceived as possessing the same degree of materiality. Something is still present, no doubt, and so the dream is in a sense objective; but the reality is less like a tangible material object, and is transformed more or less completely into something unsubstantial, spiritual, and phantasmal. On the other hand, the dream is objective in the sense of being a message or revelation from some actual divine personage. The essence of the dream, so to speak, lies in the fact that it conveys to the dreamer something which the divine personage wishes him to know, whether it be the will of this being in the shape of a command or a prohibition, or some fact as yet unknown (past or future), the knowledge of which will be of practical utility to the recipient. We may distinguish three stages in this conception of dreams :—(I) The deity sends a messenger or angel who is vaguely conceived as a spiritual being clothed in a thin material vestment; (2) the divine communicator, dispensing with the medium of a material appearance, lets his message be heard by the dreamer as the utterance of an external voice; (3) he discloses his purpose by causing to pass before the soul a vision which is not distinctly conceived as objective, but rather as something mysteriously imprinted on the mind.

The divine communication which thus makes use of the medium of a dream will, it is plain, vary considerably in the degree of its intelligibility. Sometimes the meaning of the message is obvious and unmistakable. The actions to be performed and the facts to be known are revealed plainly and directly. This will be the case for the most part with the first and second forms of dream-communication. At t’mes, too, the divinely created vision may distinctly picture some coming event in the individual or national life. On the other hand, the communication may be disguised and only partially divulged by symbol, in which case there arises the necessity of an art of interpretation. Thus at times the oral utterance may assume the form of a dim oracular declaration which calls for careful attention and a certain skill in the application of verbal figures. It is, however, in the last form of dream-revelation that we find the greatest demands made on the interpreter’s art. It follows from what has been said respecting the novelty of dream-combinations that many of the visual images which make up so large a bulk of our dreams cannot easily be fitted to any actual order of events. Hence, if such dreams are to be interpreted as having a bearing on actual events, they must be regarded as figurative or symbolic. Accordingly we find that the symbolic function of dreams has been fully recognized in all the theories of dreaming now dealt with. It seems to have been assumed that the normal mode of divine communication to man during sleep was that of such a figurative dream. And agreeably with this supposition the task of deciphering dream-symbols gradually grew into a skilled art, which became the prerogative of a certain class of experts,—as prophets, divinators, or magicians.

A very brief historical review of this religious theory of dreams must here suffice. Among the Oriental peoples this view of dreams was the prevailing one. We find, however, great differences in the mode of interpretation adopted. Among the ancient Hebrews, for example, we find all the three forms of dream-communication mentioned above. As to interpretation there seem to have been no definite rules, and the procedure followed resolves itself into an attempt to discover the most natural or least forced application of the persons, objects, and relations of the dream to some existing persons, social circumsrtances, and events. This mode of interpretation clearly left wide scope for individual skill. In the Persian scheme of interpretation, on the other hand, so far as we can judge of it from the compilations of a later age, the art of dream-interpretation, oneirocritics, or oneiromancy, was defined and fixed in a number of rules. Thus in the work known under the name of the Sifat-i-Sirozah, minute and elaborate prescriptions are given for interpreting various classes of dreams according to the particular day of the month on which they occur. A similar systematization of the rules of dream-interpretation is to be met with among the Arabs (see HOnirocrite Mussulman, par Gabdorrhachaman, traduction de Pierre Vattier.) In such cases, it is plain, the interpretation of dreams involved less of individual genius or inspiration, and became a more mechanical process, involving only careful knowledge of formulae, and one which could be easily communicated. Such a state of things points to the transition of dream-lore from the stage of au esoteric mystery to that of a communicable science. Among the Greeks and Romans the religious view of dreams is to be found in popular literature as well as in philosophic writings. In Homer, dreams are distinctly said to be sent by the gods and goddesses, as in the expression θcio<s wαpoς, and it is implied that they may be intended to deceive the subject of them (e.g., Agamemnon’s dream, Iliad, book ii.). Similarly the dramatists frequently speak of foreknowledge divinely communicated by dreams {e.g., Clytemnaestra’s prescience as to the fall of Troy in the Agamemnon of Aeschylus is ascribed to a dream). The popular view was countenanced to a certain extent by philosophers. Thus Plato found room in his mystic scheme of knowledge for the idea of a divine manifestation to the soul in sleep. In the Timaeus (chaps, xlvi. and xlvii.) a prophetic character is distinctly assigned to the images of dreams. These divine inspirations (divinations) are not, however, given to the rational soul, but to the lower appetitive soul through the medium of the sensible images of rational truths which are reflected on the liver, an organ contiguous with the bodily seat of the appetitive soul. These prophetic visions are received only when the reasoning faculty is fettered by sleep or alienated by disease and enthusiasm. In this way the divine artificer has gi.en to the inferior regions of the soul a certain substitute for rational knowledge. At the same time the interpretation of the visions requires intelligence, and hence the business of receiving them and of interpreting them does not properly belong to the same persons. Even Aristotle treats the supposition of divine revelation in dreams very considerately when he writes, in the treatise 7r∈pι pαμτικ⅛ς τηs èv to?ç vπvoas, “that there is a divination concerning some things in dreams is not incredible.” The Stoics, again, to judge from Cicero’s account of their views in his De Divinatione, reasoned a priori that the gods, if they love men and are omniscient as well as all-powerful, will certainly disclose their purposes to man in sleep. Chrysippus is, on the same authority, said to have written a volume on the interpretation of dreams as divine portents. Cicero’s brother Quintus, who here defends the orthodox theory of dreams, speaks of a skilled interpretation of dreams which is a true divination, even though, like all other arts in which men have to proceed on conjecture and on artificial rules, it is not infallible. The current views of dreams of classic antiquity are supposed to be to some extent embodied iu the 'Ονειροκριτικά of Daldianus Artemidorus of Ephesus (written about the year 170). Here the interpretation of dreams is reduced to a body of elaborate rules. To dream of a particular element, as fire, air, <fcc., of a particular plant, part of the body, and so on, always signifies the same kind of event for the same kind of person. It is the over-looking of the age, social condition, <fcc., of the dreamer which, in the view of Artemidorus, leads to the abuse of dream-interpretation. He attempts to draw a distinction between ûrapoç, a vision having a real bearing on events, and lvvπviοv, a mere dream having no actual significance; but this does not, according to Liddell and Scott, correspond with classical usage. The divine origin of dreams became a doctrine of the Christian church. It appears in the writings of the fathers, being defended partly on biblical, partly on classic, authority. Synesius of Cyrene (born 375) has left a treatise on dreams (τr∈pι ενυπνίων). He puts forward certain psychological hypotheses drawn largely from Plato and Plotinus and ascribes to the imagination (which is intermediate between the soul and the animal part) the power of accompanying the soul in its flights to the celestial regions, and so of sharing in the contemplation of divine truths. Syn esius exalts the rank of dreaming among the arts of divination, setting it far above other modes of prophecy as being most simple and sure, open to all, unencumbered with expensive and laborious preparations, and so on. He affirms that he has repeatedly found dreams of service in arranging his ideas, and in improving his style of composition. Mediaeval and modern Christian theologians have continued to attribute dreams, or, more accurately, certain orders of dream, to the intermediate agency of the divine Being. The popular theory of dreams to be met with among the later European peoples bears the impress of that folk-lore which developed itself in the Middle Ages under influences partly Christian, partly pagan. Dreams were referred to a variety of supernatural agencies, including not only God and the devil, but also subordinate beings, as fairy, fiend (incubus), &c. Further, the art of interpreting dreams according to definite rules (oneiromancy) was developed to a very high point. (See Brand, Popular Antiquities, vol. iii. Dictionary of Dreams). In our own times certain restricted classes of dreams are customarily associated with the action of benevolent or malignant beings. On the other hand, people are now wont to interpret dreams as omens or signs without distinctly attributing them to any supernatural agent. This view of dreams forms the transition-point between the religious and the scientific theories.

(c) The Dream as a Subjective Phenomenon Dependent on Natural Causes.— While the theory of the divine or supernatural origin of dreams has thus held its ground so long, there has been gradually growing up from an early period of human history a more scientific conception of the phenomenon as dependent on natural laws (of mind and body). Psychologists and physiologists alike have approached the subject from their respective points of view, and sought to explain the phenomena of dreaming as natural events. The first germs of a scientific theory of dreams are to be found in antiquity. Thus Democritus, from whom the Epicureans derived their theory, held that dreams are the product of the simulacra or phantasms of corporeal objects which are constantly floating in the atmosphere, and which attack the soul during repose. Again, Plato speaks in the Republic of dreaming as illustrating the dominant mental impulses and habits of the individual (unchecked appetite, and temperance with intellectual pursuits), and thus connects it with the normal waking operations of feeling and thought. Aristotle in his short treatise on dreams (πepι ενυπνίων) refers dreaming to the action of objects of outward sense which leave behind impressions on the soul and bodily frame. Dreaming is said to be the function of the sensitive part of the mind, but of this so far as phantastic; and a dream is defined as “the phantasm arising from the motion of sensible perceptions when it presents itself...