Aristotle · a new plain-English translation from the original language
1| ON DREAMS AND DIVINATION IN SLEEP. As for the divination that occurs in sleep and is said to come about from dreams, it is neither easy to dismiss nor easy to be persuaded of. The fact that everyone, or most people, suppose that dreams have some significance lends it credibility, as something said on the basis of experience; and that divination should hold for some particular cases of dreaming is not incredible, for there is some account to be given of it, and this might lead one to think the same of dreams generally. But the fact that we can see no reasonable cause by which it might come about makes one distrustful of it. For the notion that a god is the sender, besides being unreasonable on other counts, is also strange in that he would not send dreams to the best and wisest people but to ordinary ones. And once the causal role of the god is set aside, none of the other causes proposed appears reasonable either; for that certain people should foresee events at the Pillars of Heracles or on the Borysthenes would seem to be beyond our capacity to find the origin of. It is necessary, then, that dreams be either causes, or signs, of the things that happen, or else coincidences — either all of these, or some of them, or only one. I call a cause, for instance, the moon in relation to the sun's eclipse, and fatigue in relation to fever; a sign, the entry of the star in relation to the eclipse, and roughness of the tongue in relation to having a fever; and a coincidence, the sun's eclipsing while a man happens to be walking;
2| for this is neither a sign of the eclipse nor its cause, nor is the eclipse a sign or cause of the walking. Hence none of the coincidences occurs either always or for the most part. Is it the case, then, that some dreams are causes and others signs, for instance of what happens in the body? At any rate the more discerning among physicians say that one must pay very close attention to dreams; and it is reasonable for those who are not specialists but who look into such things and philosophize about them to hold this view as well. For the motions that occur during the day, unless they are very great and forceful, are overshadowed by the greater motions of waking life. But in sleep the opposite holds: even small motions seem great. This is clear from what often happens during sleep: people think they are being struck by thunderbolts and hearing thunderclaps when only faint sounds are occurring in their ears, and think they are enjoying honey and sweet flavors when only a tiny bit of phlegm is trickling down, and think they are walking through fire and growing intensely hot when only a slight warmth is occurring around certain parts. When they wake up, these things are plainly of this character. So then, since the beginnings of all things are small, it is clear that this holds also for the diseases and other affections about to occur in bodies.
3| It is clear, then, that these must necessarily be more apparent in sleep than in waking. But indeed it is also not unreasonable that some of the images occurring in sleep should be causes of the actions proper to each person; for just as when we are about to act, and while engaged in actions, or after having performed them, we often find ourselves involved with these very things in vivid dreams and act them out (the cause being that the motion has, as it happens, already been made a path by the wakeful origins of the day), so too, conversely, it is necessary that the motions occurring in sleep should often be the origin of the actions of the following day, because in this case too the path for their thought has already been made in the images of the night. In this way, then, it is possible for some dreams to be both signs and causes. But most dreams resemble coincidences — especially all those that are disjointed and those whose origin does not lie in the dreamers themselves but concern sea-battles and events happening far away; for it is likely that the same holds of these as when something a person happens to be remembering actually comes to pass — for what prevents this from happening in dreams as well? Indeed it is more likely that many such things should occur. So then, just as the remembering of something is neither a sign nor a cause of its actually coming about, so too in that case the dream is, for the one who saw it, neither a sign nor a cause of the outcome, but a coincidence.
4| That is also why many dreams do not come true: coincidences occur neither always nor for the most part. In general, since some of the other animals dream as well, dreams could not be sent by a god, nor do they occur for that purpose — they are, however, of the order of nature's spirits (daimonic), for nature is daimonic, not divine. Here is a sign of this: quite ordinary people are prescient and have vivid, straightforward dreams, which shows it is not a god who sends them, but rather that those whose nature is, so to speak, talkative and melancholic see all sorts of visions; for because their minds are set in motion in many and various ways, they hit upon likenesses to actual events, being lucky in this the way some people are lucky at guessing odd or even. As the saying goes, if you throw the dice many times, you will get one throw different from another, and this is what happens in their case too. That many dreams do not come true is nothing strange — no more strange than that the signs given by things in the body, or in the heavens, such as signs of rain or of wind, should sometimes fail; for if another motion occurs that is more decisive than the one from whose impending occurrence the sign arose, then the event does not come about. And many things well deliberated, and due to be carried out, have been undone by other, more decisive causes. For in general not everything that is about to happen actually happens, nor is what will be the same as what is about to be; but nonetheless these must be called origins, from which the outcome was not in fact brought to completion, and by nature they are signs of certain things that did not occur.
5| Concerning those dreams that do not have origins of the kind we have described, but that lie beyond the ordinary range either in time or in place or in magnitude, or that have none of these features but nonetheless do not have their origins within the dreamers themselves — if the foreseeing in these cases does not come about by coincidence, it would more likely be of the following sort, rather than as Democritus says, who attributes it to images and emanations. For just as when something sets water or air in motion, this in turn sets something else in motion, and even once the original mover has stopped, the resulting motion continues on for some distance though the original mover is no longer present, so too nothing prevents some motion and some perceptible impression from reaching the souls of those who are dreaming — the very things from which Democritus makes his images and emanations — and, arriving wherever they happen to arrive, being more perceptible at night because during the day, being carried along, they are more readily dissolved (for the air is less disturbed at night, since nights are calmer), and producing a perception in the body on account of sleep, because sleepers are more aware of even small internal motions than waking people are. These motions produce the images from which people foresee the things that are going to happen concerning such matters. And this is why this experience happens to ordinary people and not to the wisest ones.
6| For if a god were the sender, it would occur during the day as well, and to the wise; as it is, it is likely that ordinary people should be the ones to foresee things, since the thought of such people is not given to reflection but is, as it were, empty and vacant of everything, and once set in motion is led along by whatever sets it moving. And the reason some people in ecstatic states foresee things is that their own proper motions do not get in the way but are, so to speak, brushed aside, so that they perceive the foreign motions most of all. And the fact that some people have vivid, straightforward dreams, and that acquaintances especially foresee things about their acquaintances, comes about because acquaintances think about one another the most; for just as people recognize and perceive those who are dear to them fastest even from a distance, so too with their motions — the motions of people we know are more recognizable to us. Melancholic people, because of the intensity of their motions, are like people throwing from far off, and hit the mark well. And because of their changeable temperament, whatever comes next appears quickly to them in imagination; for just as in the poems of Philaegides, and as madmen do, they string together one thing connected to the next by mere resemblance — for instance Aphrodite — and in this way carry the chain forward. Further, because of the intensity of their motion, it is not knocked out of the way by some other motion. The most skillful judge of dreams is the one who is able to discern resemblances; for judging straightforward dreams is within anyone's ability.
7| By resemblances I mean this: the images that occur are similar to the reflections in water, just as we said before. There, if the motion of the water is great, the reflection and the images bear no resemblance at all to the real things. A person would be clever at judging reflections, then, if he could quickly perceive and discern, in images that are scattered and distorted, that it is the image of a man or a horse or whatever it may be. And in the case of dreaming, too, this same thing holds in a similar way; for motion cuts off accurate dreaming. What sleep and dreaming are, then, and for what cause each of them occurs, and further, concerning divination from dreams, has now been stated.