350 BC ON DREAMS by Aristotle translated by J. I. Beare 1 WE must, in the next place, inesti!ate the sub"ect o# the dream, and #irst in$uire to %hich o# the #aculties o# the soul it presents itsel#, i.e. %hether the a##ection is one %hich pertains to the #aculty o# intelli!ence or to that o# sense&perception' #or these are the only #aculties %ithin us by %hich %e ac$uire (no%led!e. I#, then, the exercise o# the #aculty o# si!ht is actual seein!, that o# the auditory #aculty, hearin!, and, in !eneral that o# the #aculty o# sense&perception, perceiin!' and i# there are some perceptions common to the senses, such as #i!ure, ma!nitude, motion, )c., %hile there are others, as colour, sound, taste, peculiar *each to its o%n sense+' and #urther, i# all creatures, %hen the eyes are closed in sleep, are unable to see, and the analo!ous statement is true o# the other senses, so that mani#estly %e perceie nothin! %hen asleep' %e may conclude that it is not by sense&perception %e perceie a dream. But neither is it by opinion that %e do so. ,or *in dreams+ %e not only assert, e.!. that some ob"ect approachin! is a man or a horse *%hich %ould be an exercise o# opinion+, but that the ob"ect is %hite or beauti#ul, points on %hich opinion %ithout sense&perception asserts nothin! either truly or #alsely. It is, ho%eer, a #act that the soul ma(es such assertions in sleep. We seem to see e$ually %ell that the approachin! #i!ure is a man, and that it is %hite. *In dreams+, too, %e thin( somethin! else, oer and aboe the dream presentation, "ust as %e do in %a(in! moments %hen %e perceie somethin!' #or %e o#ten also reason about that %hich %e perceie. -o, too, in sleep %e sometimes hae thou!hts other than the mere phantasms immediately be#ore our minds. .his %ould be mani#est to any one %ho should attend and try, immediately on arisin! #rom sleep, to remember *his dreamin! experience+. .here are cases o# persons %ho hae seen such dreams, those, #or example, %ho beliee themseles to be mentally arran!in! a !ien list o# sub"ects accordin! to the mnemonic rule. .hey #re$uently #ind themseles en!a!ed in somethin! else besides the dream, i/. in settin! a phantasm %hich they enisa!e into its mnemonic position. 0ence it is plain that not eery 1phantasm1 in sleep is a mere dream&ima!e, and that the #urther thin(in! %hich %e per#orm then is due to an exercise o# the #aculty o# opinion. -o much at least is plain on all these points, i/. that the #aculty by %hich, in %a(in! hours, %e are sub"ect to illusion %hen a##ected by disease, is identical %ith that %hich produces illusory e##ects in sleep. -o, een %hen persons are in excellent health, and (no% the #acts o# the case per#ectly %ell, the sun, neertheless, appears to them to be only a #oot %ide. 2o%, %hether the presentatie #aculty o# the soul be identical %ith, or di##erent #rom, the #aculty o# sense&perception, in either case the illusion does not occur %ithout our actually seein! or *other%ise+ perceiin! somethin!. Een to see %ron!ly or to hear %ron!ly can happen only to one %ho sees or hears somethin! real, thou!h not exactly %hat he supposes. But %e hae assumed that in sleep one neither sees, nor hears, nor exercises any sense %hateer. 3erhaps %e may re!ard it as true that the dreamer sees nothin!, yet as #alse that his #aculty o# sense&perception is una##ected, the #act bein! that the sense o# seein! and the other senses may possibly be then in a certain %ay a##ected, %hile each o# these a##ections, as duly as %hen he is a%a(e, !ies its impulse in a certain manner to his *primary+ #aculty o# sense, thou!h not in precisely the same manner as %hen he is a%a(e. -ometimes, too, opinion says *to dreamers+ "ust as to those %ho are a%a(e, that the ob"ect seen is an illusion' at other times it is inhibited, and becomes a mere #ollo%er o# the phantasm. It is plain there#ore that this a##ection, %hich %e name 1dreamin!1, is no mere exercise o# opinion or intelli!ence, but yet is not an a##ection o# the #aculty o# perception in the simple sense. I# it %ere the latter it %ould be possible *%hen asleep+ to hear and see in the simple sense. 0o% then, and in %hat manner, it ta(es place, is %hat %e hae to examine. 4et us assume, %hat is indeed clear enou!h, that the a##ection *o# dreamin!+ pertains to sense&perception as surely as sleep itsel# does. ,or sleep does not pertain to one or!an in animals and dreamin! to another' both pertain to the same or!an. But since %e hae, in our %or( 5n the -oul, treated o# presentation, and the #aculty o# presentation is identical %ith that o# sense&perception, thou!h the essential notion o# a #aculty o# presentation is di##erent #rom that o# a #aculty o# sense&perception' and since presentation is the moement set up by a sensory #aculty %hen actually dischar!in! its #unction, %hile a dream appears to be a presentation 6#or a presentation %hich occurs in sleep&%hether simply or in some particular %ay&is %hat %e call a dream78 it mani#estly #ollo%s that dreamin! is an actiity o# the #aculty o# sense&perception, but belon!s to this #aculty $ua presentatie. 2 We can best obtain a scienti#ic ie% o# the nature o# the dream and the manner in %hich it ori!inates by re!ardin! it in the li!ht o# the circumstances attendin! sleep. .he ob"ects o# sense&perception correspondin! to each sensory or!an produce sense&perception in us, and the a##ection due to their operation is present in the or!ans o# sense not only %hen the perceptions are actuali/ed, but een %hen they hae departed. What happens in these cases may be compared %ith %hat happens in the case o# pro"ectiles moin! in space. ,or in the case o# these the moement continues een %hen that %hich set up the moement is no lon!er in contact *%ith the thin!s that are moed+. ,or that %hich set them in motion moes a certain portion o# air, and this, in turn, bein! moed excites motion in another portion' and so, accordin!ly, it is in this %ay that *the bodies+, %hether in air or in li$uids, continue moin!, until they come to a standstill. .his %e must li(e%ise assume to happen in the case o# $ualitatie chan!e' #or that part %hich *#or example+ has been heated by somethin! hot, heats *in turn+ the part next to it, and this propa!ates the a##ection continuously on%ards until the process has come round to its point o# ori!ination. .his must also happen in the or!an %herein the exercise o# sense&perception ta(es place, since sense&perception, as reali/ed in actual perceiin!, is a mode o# $ualitatie chan!e. .his explains %hy the a##ection continues in the sensory or!ans, both in their deeper and in their more super#icial parts, not merely %hile they are actually en!a!ed in perceiin!, but een a#ter they hae ceased to do so. .hat they do this, indeed, is obious in cases %here %e continue #or some time en!a!ed in a particular #orm o# perception, #or then, %hen %e shi#t the scene o# our perceptie actiity, the preious a##ection remains' #or instance, %hen %e hae turned our !a/e #rom sunli!ht into dar(ness. ,or the result o# this is that one sees nothin!, o%in! to the excited by the li!ht still subsistin! in our eyes. Also, %hen %e hae loo(ed steadily #or a lon! %hile at one colour, e.!. at %hite or !reen, that to %hich %e next trans#er our !a/e appears to be o# the same colour. A!ain i#, a#ter hain! loo(ed at the sun or some other brilliant ob"ect, %e close the eyes, then, i# %e %atch care#ully, it appears in a ri!ht line %ith the direction o# ision 6%hateer this may be7, at #irst in its o%n colour' then it chan!es to crimson, next to purple, until it becomes blac( and disappears. And also %hen persons turn a%ay #rom loo(in! at ob"ects in motion, e.!. riers, and especially those %hich #lo% ery rapidly, they #ind that the isual stimulations still present themseles, #or the thin!s really at rest are then seen moin!8 persons become ery dea# a#ter hearin! loud noises, and a#ter smellin! ery stron! odours their po%er o# smellin! is impaired' and similarly in other cases. .hese phenomena mani#estly ta(e place in the %ay aboe described. .hat the sensory or!ans are acutely sensitie to een a sli!ht $ualitatie di##erence *in their ob"ects+ is sho%n by %hat happens in the case o# mirrors' a sub"ect to %hich, een ta(in! it independently, one mi!ht deote close consideration and in$uiry. At the same time it becomes plain #rom them that as the eye *in seein!+ is a##ected *by the ob"ect seen+, so also it produces a certain e##ect upon it. I# a %oman chances durin! her menstrual period to loo( into a hi!hly polished mirror, the sur#ace o# it %ill !ro% cloudy %ith a blood&coloured ha/e. It is ery hard to remoe this stain #rom a ne% mirror, but easier to remoe #rom an older mirror. As %e hae said be#ore, the cause o# this lies in the #act that in the act o# si!ht there occurs not only a passion in the sense or!an acted on by the polished sur#ace, but the or!an, as an a!ent, also produces an action, as is proper to a brilliant ob"ect. ,or si!ht is the property o# an or!an possessin! brilliance and colour. .he eyes, there#ore, hae their proper action as hae other parts o# the body. Because it is natural to the eye to be #illed %ith blood&essels, a %oman1s eyes, durin! the period o# menstrual #lux and in#lammation, %ill under!o a chan!e, althou!h her husband %ill not note this since his seed is o# the same nature as that o# his %i#e. .he surroundin! atmosphere, throu!h %hich operates the action o# si!ht, and %hich surrounds the mirror also, %ill under!o a chan!e o# the same sort that occurred shortly be#ore in the %oman1s eyes, and hence the sur#ace o# the mirror is li(e%ise a##ected. And as in the case o# a !arment, the cleaner it is the more $uic(ly it is soiled, so the same holds true in the case o# the mirror. ,or anythin! that is clean %ill sho% $uite clearly a stain that it chances to receie, and the cleanest ob"ect sho%s up een the sli!htest stain. A bron/e mirror, because o# its shininess, is especially sensitie to any sort o# contact 6the moement o# the surroundin! air acts upon it li(e a rubbin! or pressin! or %ipin!7' on that account, there#ore, %hat is clean %ill sho% up clearly the sli!htest touch on its sur#ace. It is hard to cleanse smud!es o## ne% mirrors because the stain penetrates deeply and is su##used to all parts' it penetrates deeply because the mirror is not a dense medium, and is su##used %idely because o# the smoothness o# the ob"ect. 5n the other hand, in the case o# old mirrors, stains do not remain because they do not penetrate deeply, but only smud!e the sur#ace. ,rom this there#ore it is plain that stimulatory motion is set up een by sli!ht di##erences, and that sense&perception is $uic( to respond to it' and #urther that the or!an %hich perceies colour is not only a##ected by its ob"ect, but also reacts upon it. ,urther eidence to the same point is a##orded by %hat ta(es place in %ines, and in the manu#acture o# un!uents. ,or both oil, %hen prepared, and %ine become rapidly in#ected by the odours o# the thin!s near them' they not only ac$uire the odours o# the thin!s thro%n into or mixed %ith them, but also those o# the thin!s %hich are placed, or %hich !ro%, near the essels containin! them. In order to ans%er our ori!inal $uestion, let us no%, there#ore, assume one proposition, %hich is clear #rom %hat precedes, i/. that een %hen the external ob"ect o# perception has departed, the impressions it has made persist, and are themseles ob"ects o# perception8 and *let us assume+, besides, that %e are easily deceied respectin! the operations o# sense&perception %hen %e are excited by emotions, and di##erent persons accordin! to their di##erent emotions' #or example, the co%ard %hen excited by #ear, the amorous person by amorous desire' so that, %ith but little resemblance to !o upon, the #ormer thin(s he sees his #oes approachin!, the latter, that he sees the ob"ect o# his desire' and the more deeply one is under the in#luence o# the emotion, the less similarity is re$uired to !ie rise to these illusory impressions. .hus too, both in #its o# an!er, and also in all states o# appetite, all men become easily deceied, and more so the more their emotions are excited. .his is the reason too %hy persons in the delirium o# #eer sometimes thin( they see animals on their chamber %alls, an illusion arisin! #rom the #aint resemblance to animals o# the mar(in!s thereon %hen put to!ether in patterns' and this sometimes corresponds %ith the emotional states o# the su##erers, in such a %ay that, i# the latter be not ery ill, they (no% %ell enou!h that it is an illusion' but i# the illness is more seere they actually moe accordin! to the appearances. .he cause o# these occurrences is that the #aculty in irtue o# %hich the controllin! sense "ud!es is not identical %ith that in irtue o# %hich presentations come be#ore the mind. A proo# o# this is, that the sun presents itsel# as only a #oot in diameter, thou!h o#ten somethin! else !ainsays the presentation. A!ain, %hen the #in!ers are crossed, the one ob"ect *placed bet%een them+ is #elt *by the touch+ as t%o' but yet %e deny that it is t%o' #or si!ht is more authoritatie than touch. 9et, i# touch stood alone, %e should actually hae pronounced the one ob"ect to be t%o. .he !round o# such #alse "ud!ements is that any appearances %hateer present themseles, not only %hen its ob"ect stimulates a sense, but also %hen the sense by itsel# alone is stimulated, proided only it be stimulated in the same manner as it is by the ob"ect. ,or example, to persons sailin! past the land seems to moe, %hen it is really the eye that is bein! moed by somethin! else *the moin! ship.+ 3 ,rom this it is mani#est that the stimulatory moements based upon sensory impressions, %hether the latter are deried #rom external ob"ects or #rom causes %ithin the body, present themseles not only %hen persons are a%a(e, but also then, %hen this a##ection %hich is called sleep has come upon them, %ith een !reater impressieness. ,or by day, %hile the senses and the intellect are %or(in! to!ether, they 6i.e. such moements7 are extruded #rom consciousness or obscured, "ust as a smaller is beside a lar!er #ire, or as small beside !reat pains or pleasures, thou!h, as soon as the latter hae ceased, een those %hich are tri#lin! emer!e into notice. But by ni!ht *i.e. in sleep+ o%in! to the inaction o# the particular senses, and their po%erlessness to reali/e themseles, %hich arises #rom the re#lux o# the hot #rom the exterior parts to the interior, they *i.e. the aboe 1moements1+ are borne in to the head $uarters o# sense&perception, and there display themseles as the disturbance 6o# %a(in! li#e7 subsides. We must suppose that, li(e the little eddies %hich are bein! eer #ormed in riers, so the sensory moements are each a continuous process, o#ten remainin! li(e %hat they %ere %hen #irst started, but o#ten, too, bro(en into other #orms by collisions %ith obstacles. .his *last mentioned point+, moreoer, !ies the reason %hy no dreams occur in sleep immediately a#ter meals, or to sleepers %ho are extremely youn!, e.!. to in#ants. .he internal moement in such cases is excessie, o%in! to the heat !enerated #rom the #ood. 0ence, "ust as in a li$uid, i# one ehemently disturbs it, sometimes no re#lected ima!e appears, %hile at other times one appears, indeed, but utterly distorted, so as to seem $uite unli(e its ori!inal' %hile, %hen once the motion has ceased, the re#lected ima!es are clear and plain' in the same manner durin! sleep the phantasms, or residuary moements, %hich are based upon the sensory impressions, become sometimes $uite obliterated by the aboe described motion %hen too iolent' %hile at other times the si!hts are indeed seen, but con#used and %eird, and the dreams *%hich then appear+ are unhealthy, li(e those o# persons %ho are atrabilious, or #eerish, or intoxicated %ith %ine. ,or all such a##ections, bein! spirituous, cause much commotion and disturbance. In san!uineous animals, in proportion as the blood becomes calm, and as its purer are separated #rom its less pure elements, the #act that the moement, based on impressions deried #rom each o# the or!ans o# sense, is presered in its inte!rity, renders the dreams healthy, causes a *clear+ ima!e to present itsel#, and ma(es the dreamer thin(, o%in! to the e##ects borne in #rom the or!an o# si!ht, that he actually sees, and o%in! to those %hich come #rom the or!an o# hearin!, that he really hears' and so on %ith those also %hich proceed #rom the other sensory or!ans. ,or it is o%in! to the #act that the moement %hich reaches the primary or!an o# sense comes #rom them, that one een %hen a%a(e beliees himsel# to see, or hear, or other%ise perceie' "ust as it is #rom a belie# that the or!an o# si!ht is bein! stimulated, thou!h in reality not so stimulated, that %e sometimes erroneously declare ourseles to see, or that, #rom the #act that touch announces t%o moements, %e thin( that the one ob"ect is t%o. ,or, as a rule, the !oernin! sense a##irms the report o# each particular sense, unless another particular sense, more authoritatie, ma(es a contradictory report. In eery case an appearance presents itsel#, but %hat appears does not in eery case seem real, unless %hen the decidin! #aculty is inhibited, or does not moe %ith its proper motion. :oreoer, as %e said that di##erent men are sub"ect to illusions, each accordin! to the di##erent emotion present in him, so it is that the sleeper, o%in! to sleep, and to the moements then !oin! on in his sensory or!ans, as %ell as to the other #acts o# the sensory process, *is liable to illusion+, so that the dream presentation, thou!h but little li(e it, appears as some actual !ien thin!. ,or %hen one is asleep, in proportion as most o# the blood sin(s in%ards to its #ountain *the heart+, the internal *sensory+ moements, some potential, others actual accompany it in%ards. .hey are so related *in !eneral+ that, i# anythin! moe the blood, some one sensory moement %ill emer!e #rom it, %hile i# this perishes another %ill ta(e its place' %hile to one another also they are related in the same %ay as the arti#icial #ro!s in %ater %hich seerally rise *in #ixed succesion+ to the sur#ace in the order in %hich the salt *%hich (eeps them do%n+ becomes dissoled. .he residuary moements are li(e these8 they are %ithin the soul potentially, but actuali/e themseles only %hen the impediment to their doin! so has been relaxed' and accordin! as they are thus set #ree, they be!in to moe in the blood %hich remains in the sensory or!ans, and %hich is no% but scanty, %hile they possess erisimilitude a#ter the manner o# cloud&shapes, %hich in their rapid metamorphoses one compares no% to human bein!s and a moment a#ter%ards to centaurs. Each o# them is ho%eer, as has been said, the remnant o# a sensory impression ta(en %hen sense %as actuali/in! itsel#' and %hen this, the true impression, has departed, its remnant is still immanent, and it is correct to say o# it, that thou!h not actually ;oris(os, it is li(e ;oris(os. ,or %hen the person %as actually perceiin!, his controllin! and "ud!in! sensory #aculty did not call it ;oris(os, but, prompted by this *impression+, called the !enuine person yonder ;oris(os. Accordin!ly, this sensory impulse, %hich, %hen actually perceiin!, it *the controllin! #aculty+ describes 6unless completely inhibited by the blood7, it no% *in dreams+ %hen $uasi&perceiin!, receies #rom the moements persistin! in the sense&or!ans, and mista(es it&an impulse that is merely li(e the true *ob"ectie+ impressionor the true impression itsel#, %hile the e##ect o# sleep is so !reat that it causes this mista(e to pass unnoticed. Accordin!ly, "ust as i# a #in!er be inserted beneath the eyeball %ithout bein! obsered, one ob"ect %ill not only present t%o isual ima!es, but %ill create an opinion o# its bein! t%o ob"ects' %hile i# it *the #in!er+ be obsered, the presentation %ill be the same, but the same opinion %ill not be #ormed o# it' exactly so it is in states o# sleep8 i# the sleeper perceies that he is asleep, and is conscious o# the sleepin! state durin! %hich the perception comes be#ore his mind, it presents itsel# still, but somethin! %ithin him spea(s to this e##ect8 1the ima!e o# ;oris(os presents itsel#, but the real ;oris(os is not present1' #or o#ten, %hen one is asleep, there is somethin! in consciousness %hich declares that %hat then presents itsel# is but a dream. I#, ho%eer, he is not a%are o# bein! asleep, there is nothin! %hich %ill contradict the testimony o# the bare presentation. .hat %hat %e here ur!e is true, i.e. that there are such presentatie moements in the sensory or!ans, any one may conince himsel#, i# he attends to and tries to remember the a##ections %e experience %hen sin(in! into slumber or %hen bein! a%a(ened. 0e %ill sometimes, in the moment o# a%a(enin!, surprise the ima!es %hich present themseles to him in sleep, and #ind that they are really but moements lur(in! in the or!ans o# sense. And indeed some ery youn! persons, i# it is dar(, thou!h loo(in! %ith %ide open eyes, see multitudes o# phantom #i!ures moin! be#ore them, so that they o#ten coer up their heads in terror. ,rom all this, then, the conclusion to be dra%n is, that the dream is a sort o# presentation, and, more particularly, one %hich occurs in sleep' since the phantoms "ust mentioned are not dreams, nor is any other a dream %hich presents itsel# %hen the sense&perceptions are in a state o# #reedom. 2or is eery presentation %hich occurs in sleep necessarily a dream. ,or in the #irst place, some persons *%hen asleep+ actually, in a certain %ay, perceie sounds, li!ht, saour, and contact' #eebly, ho%eer, and, as it %ere, remotely. ,or there hae been cases in %hich persons %hile asleep, but %ith the eyes partly open, sa% #aintly in their sleep 6as they supposed7 the li!ht o# a lamp, and a#ter%ards, on bein! a%a(ened, strai!ht%ay reco!ni/ed it as the actual li!ht o# a real lamp' %hile, in other cases, persons %ho #aintly heard the cro%in! o# coc(s or the bar(in! o# do!s identi#ied these clearly %ith the real sounds as soon as they a%o(e. -ome persons, too, return ans%ers to $uestions put to them in sleep. ,or it is $uite possible that, o# %a(in! or sleepin!, %hile the one is present in the ordinary sense, the other also should be present in a certain %ay. But none o# these occurrences should be called a dream. 2or should the true thou!hts, as distinct #rom the mere presentations, %hich occur in sleep *be called dreams+. .he dream proper is a presentation based on the moement o# sense impressions, %hen such presentation occurs durin! sleep, ta(in! sleep in the strict sense o# the term. .here are cases o# persons %ho in their %hole lies hae neer had a dream, %hile others dream %hen considerably adanced in years, hain! neer dreamed be#ore. .he cause o# their not hain! dreams appears some%hat li(e that %hich operates in the case o# in#ants, and *that %hich operates+ immediately a#ter meals. It is intelli!ible enou!h that no dream&presentation should occur to persons %hose natural constitution is such that in them copious eaporation is borne up%ards, %hich, %hen borne bac( do%n%ards, causes a lar!e $uantity o# motion. But it is not surprisin! that, as a!e adances, a dream should at len!th appear to them. Indeed, it is ineitable that, as a chan!e is %rou!ht in them in proportion to a!e or emotional experience, this reersal *#rom non&dreamin! to dreamin!+ should occur also. THE END