Influence of reverie in the production of hallucinations - Distinctions to be established - On the reverie of Orientals - Belief in the supernatural - 1. Recognized, spontaneous, ephemeral, and prolonged hallucinations; 2. Unrecognised hallucinations - Causes of hallucinations - Observations borrowed from historical personages - Their importance - Recapitulation.

The proposition in this book which is most disputed is that of hallucinations as consistent with reason. In order to bring forward all the evidence of which we think it susceptible, we must penetrate into the region of psychological facts, analyze the different states in which hallucination is normally produced, and illustrate argument by well-selected facts. Before entering on these researches, it will be well to notice an error inseparable from the subject, and into which it is usual to fall: I mean the analogies of reason and lunacy.* So long as a proper distance from the invisible limits of these two worlds is maintained, illusion is impossible; but the frontier once invaded, confusion commences, and it becomes very difficult to distinguish true from erroneous ideas, reality from falsehood.

Let us take an example: The idea of God is universal; his justice is an attribute that cannot be separated from his essence; if, however, the idea of justice should touch the borders of the fatal circle, it assumes the appearance of inflexible severity, terror, chastisement, and damnation, and too often leads to suicide. There is no idea, which is drawn into this orbit, but undergoes this terrible metamorphosis. The same phenomenon takes place with images. In many cases visible to the senses, but recognized as memories, reminiscences, creations - sometimes accepted as the effect of supernatural power - their usual character is not to cause any disturbance of the intellect, nor exercise any unhappy influence on the actions of life. It is not thus when the image presents an actual form to the mind which slavishly obeys it; the hallucination passes from a physiological to a pathological condition, and thence leads to insanity.

* F. Lelut, Le Demon de Socrate, Recherches des Analogies de la Folie et de la Raison, one vol. in 8vo. p. 321, Paris, 1836. - Moreau, Un chapitre oublie de la Pathologie Mentale, Paris, 1830.

The existence of images, or rather of physiological hallucinations,* is placed beyond all doubt by thousands of physical and moral facts. Indeed, they may be caused by optical or acoustic illusion.

Brewster, in his Letter* on Natural Magic† has related an experiment by Newton, which proves that any one can, at his pleasure, create hallucinations. That great philosopher, after having attracted the sun to a mirror, directed his glance by chance to an obscure part of the room; he was much surprised to see the solar spectrum reproduced, and exhibited by degrees, with all the colors and brilliancy of the sun itself. The hallucination occurred as frequently as he turned his eyes towards the dark spot.‡

Paterson remarks that the same phenomenon takes place when a casement is highly illuminated, and the wall afterwards looked at; the image of the casement, with its squares and its bars, is quickly developed to your gaze.§ To these two facts may be added the circumstance that individuals who concentrate their ideas on a scene, or a mountain which they may have noticed in their travels, find it reproduced with extreme fidelity.

* These remarks apply equally to illusions.

† Sir David Brewster, Letters on Natural Magic, p. 32, London, 1832.

‡ I would remark now, and once for all, that all observations borrowed from foreign authors have been translated by myself. Many physicians who have written on hallucinations have given certain quotations which they believed to be literally taken from works, more or less known, whilst I took the trouble to translate the original text. Experience at my own cost, and errors committed by those who quote at second and third hand, have long since given me the habit of applying at once to the fountain-head.

§ Paterson, Edinburgh Medical and Surgical Journal, No. cliv., January, 1843. - Memoires sur plusieurs cas d'hallucinations, avec des observations surles phenomenes et les etats morbides dans lesquels elles ont lieu, translated by A. Brierre de Boismont, Annales Medico-Psycho., 1, 3,1834.

There is a state of mind which every one has experienced, and which shows with what facility hallucination can be produced: I speak of reverie. A dear friend, M. Alfred de Vigny, writes thus on the subject: "There are two kinds of reverie - that of weak minds, and that of deep thinkers. Yes, reverie leads to a wilderness of ideas in the poor souls who are in love with thought, and desire it, without being able to obtain it, or to find in it complete and solid strength. Certainly it is a dangerous labyrinth • to those who have neither a clear sight nor a firm foot to discover their road. But reverie is the prelude to great creations in minds like that of St. Jerome, who came forth from the desert stronger than when he entered it, and reappeared, armed and mailed with his grand Christian books. With him, with St. John Chrysostom, with Descartes, with Malebranche, with Dante, with Milton, with Spinosa, reverie is force, power, health, and often even longevity. With them solitude is holy."

Meister likewise describes this creative power of reverie: "Nothing," says he, "can throw a clearer light on the habitual working of our faculty of thinking than to observe it by turns in three very different states - the state of waking, that of sleep, and that middle state between waking and sleeping, in which the external senses are rather in a state of calm and inaction than of actual torpidity; in which the activity of the internal senses becomes, as it were, isolated, and it is doubtful whether we dream or meditate. This state usually follows or precedes the repose of sleep; it is also sometimes the result of prolonged meditation on one object, or on one idea, more particularly in the silence of nature, in the obscurity of the forest, or in the midst of the shadows of night. Then a single impression, a single image, appears sometimes to remain long in the thought, and hold it, as it were, in a state of siege; then our understanding acts only by intuition. Entire scenes, pictures, complete or in part, succeed to the interior sense, now slowly, now with rapidity. We think we see, and truly see, that which we have never seen. Indeed, these are real phantoms that our imagination, by its sole power, gathers around us, happy or unhappy beneath the charm of its sorcery."