Medicine and philosophy - Classical Homeopathy Online

Aristotle on sleep and dreams 185qualification ‘when one is asleep and in so far as one is asleep’ is necessary inorder to distinguish the dream from other experiences one may have in andaround sleep; and there is a pun here, for the Greek word enhupnion, whichAristotle uses throughout for ‘dream’, literally means ‘(something) in sleep’,en hupnōi. These ‘other experiences’ have been discussed by Aristotle in thepreceding lines with the aid of examples (462 a 9–15): in sleep we sometimesperceive things which on awakening we recognise as being caused bysense-movements that actually present themselves to our sense-organs, andchildren often see frightening visions in the dark with their eyes open; andas he says in the passage quoted, in transitional states of half-sleep we mayperceive weak impressions of light and sound, we may even give answers toquestions which are being asked, and we may have thoughts in sleep aboutthe dream image. How these experiences are physiologically possible is notexplained by Aristotle, but what he says about them is highly significant intheoretical respect. Sleep and waking are not absolute opposites: when oneof them is present ‘without qualification’ (haplōs), the other may also bepresent ‘in a certain way’ (pēi ). In these transitional states between sleepingand waking, we may, after all, have some sort of direct perception of theactual state of affairs in the external world. Aristotle’s recognition of thispossibility entails an implicit modification of his earlier assertions in thefirst chapter of On Sleep and Waking, where he defined sleep and wakingas opposites and sleep as the privation of waking (453 b 26–27), and inchapter 1 of On Dreams, where he said that we cannot perceive anythingin sleep. It now turns out that we may actually perceive in sleep, thoughfaintly and unclearly. In accordance with his dream theory, Aristotle hereinsists that none of these experiences ‘in sleep’ (en hupnōi ) are ‘dreams’,that is, enhupnia in the strict sense.A remarkably modern consequence of this view is that according toAristotle the state of sleeping can be divided into different stages. Aristotledoes not show any awareness of ‘rapid eye movements’; but on theoreticalgrounds he assumes that the beginning of sleep is characterised by anabsence of dreams, because then, as a result of the process of digestion,there is too much confusion and ‘turbulence’ in the body, which disturbs thetransport of sense-movements through the blood (461 a 8ff.). Appearancesthat manifest themselves in that early stage are not dreams, Aristotle pointsout: dreams occur later, when the blood is separated into a thinner, clearerpart and a thicker, troubled part; when this process of separation of theblood is completed, we wake up (458 a 10–25). Thus dreams are experienceswhich we have when in fact we are on our way to awakening. Experiences,however, which we have just before or simultaneously with awakening and