XIII. A Rationale of sleep, of yawning, and of dreams50    The Latin version (and with it several of the Greek mss.) makes this the fourteenth chapter. The Bodleian ms. gives as its title:—“That our body is always in motion.”.

1. This life of our bodies, material and subject to flux, always advancing by way of motion, finds the power of its being in this, that it never rests from its motion: and as some river, flowing on by its own impulse, keeps the channel in which it runs well filled, yet is not seen in the same water always at the same place, but part of it glides away while part comes flowing on, so, too, the material element of our life here suffers change in the continuity of its succession of opposites by way of motion and flux, so that it never can desist from change, but in its inability to rest keeps up unceasingly its motion alternating by like ways51    Life is represented as a succession of opposite states (τῶν ἐναντίων διαδοχὴ), which yet recur again and again in the same sequence (διὰ τῶν ὁμοίων). This is illustrated in the following section.: and if it should ever cease moving it will assuredly have cessation also of its being.

2. For instance, emptying succeeds fulness, and on the other hand after emptiness comes in turn a process of filling: sleep relaxes the strain of waking, and, again, awakening braces up what had become slack: and neither of these abides continually, but both give way, each at the other’s coming; nature thus by their interchange so renewing herself as, while partaking of each in turn, to pass from the one to the other without break. For that the living creature should always be exerting itself in its operations produces a certain rupture and severance of the overstrained part; and continual quiescence of the body brings about a certain dissolution and laxity in its frame: but to be in touch with each of these at the proper times in a moderate degree is a staying-power of nature, which, by continual transference to the opposed states, gives herself in each of them rest from the other. Thus she finds the body on the strain through wakefulness, and devises relaxation for the strain by means of sleep, giving the perceptive faculties rest for the time from their operations, loosing them like horses from the chariots after the race.

3. Further, rest at proper times is necessary for the framework of the body, that the nutriment may be diffused over the whole body through the passages which it contains, without any strain to hinder its progress. For just as certain misty vapours are drawn up from the recesses of the earth when it is soaked with rain, whenever the sun heats it with rays of any considerable warmth, so a similar result happens in the earth that is in us, when the nutriment within is heated up by natural warmth; and the vapours, being naturally of upward tendency and airy nature, and aspiring to that which is above them, come to be in the region of the head like smoke penetrating the joints of a wall: then they are dispersed thence by exhalation to the passages of the organs of sense, and by them the senses are of course rendered inactive, giving way to the transit of these vapours. For the eyes are pressed upon by the eyelids when some leaden instrument52    Reading μηχανῆς with the earlier editions and (apparently) a large number of Forbes’ mss. in place of μηχανικῆς. But μολυβδίνης may be for μολυβδαίνης, as it were (I mean such a weight as that I have spoken of), lets down the eyelid upon the eyes; and the hearing, being dulled by these same vapours, as though a door were placed upon the acoustic organs, rests from its natural operation: and such a condition is sleep, when the sense is at rest in the body, and altogether ceases from the operation of its natural motion, so that the digestive processes of nutriment may have free course for transmission by the vapours through each of the passages.

4. And for this reason, if the apparatus of the organs of sense should be closed and sleep hindered by some occupation, the nervous system, becoming filled with the vapours, is naturally and spontaneously extended so that the part which has had its density increased by the vapours is rarefied by the process of extension, just as those do who squeeze the water out of clothes by vehement wringing: and, seeing that the parts about the pharynx are somewhat circular, and nervous tissue abounds there, whenever there is need for the expulsion from that part of the density of the vapours—since it is impossible that the part which is circular in shape should be separated directly, but only by being distended in the outline of its circumference—for this reason, by checking the breath in a yawn the chin is moved downwards so as to leave a hollow to the uvula, and all the interior parts being arranged in the figure of a circle, that smoky denseness which had been detained in the neighbouring parts is emitted together with the exit of the breath. And often the like may happen even after sleep when any portion of those vapours remains in the region spoken of undigested and unexhaled.

5. Hence the mind of man clearly proves its claim53    Reading δείκνυσιν, as Forbes does (apparently from all the mss. and agreeing with the earlier editt.). The Latin translation points to the reading δείκνυται to connection with his nature, itself also co-operating and moving with the nature in its sound and waking state, but remaining unmoved when it is abandoned to sleep, unless any one supposes that the imagery of dreams is a motion of the mind exercised in sleep. We for our part say that it is only the conscious and sound action of the intellect which we ought to refer to mind; and as to the fantastic nonsense which occurs to us in sleep, we suppose that some appearances of the operations of the mind are accidentally moulded in the less rational part of the soul; for the soul, being by sleep dissociated from the senses, is also of necessity outside the range of the operations of the mind; for it is through the senses that the union of mind with man takes place; therefore when the senses are at rest, the intellect also must needs be inactive; and an evidence of this is the fact that the dreamer often seems to be in absurd and impossible situations, which would not happen if the soul were then guided by reason and intellect.

6. It seems to me, however, that when the soul is at rest so far as concerns its more excellent faculties (so far, I mean, as concerns the operations of mind and sense), the nutritive part of it alone is operative during sleep, and that some shadows and echoes of those things which happen in our waking moments—of the operations both of sense and of intellect—which are impressed upon it by that part of the soul which is capable of memory, that these, I say, are pictured as chance will have it, some echo of memory still lingering in this division of the soul.

7. With these, then, the man is beguiled, not led to acquaintance with the things that present themselves by any train of thought, but wandering among confused and inconsequent delusions. But just as in his bodily operations, while each of the parts individually acts in some way according to the power which naturally resides in it, there arises also in the limb that is at rest a state sympathetic with that which is in motion, similarly in the case of the soul, even if one part is at rest and another in motion, the whole is affected in sympathy with the part; for it is not possible that the natural unity should be in any way severed, though one of the faculties included in it is in turn supreme in virtue of its active operation. But as, when men are awake and busy, the mind is supreme, and sense ministers to it, yet the faculty which regulates the body is not dissociated from them (for the mind furnishes the food for its wants, the sense receives what is furnished, and the nutritive faculty of the body appropriates to itself that which is given to it), so in sleep the supremacy of these faculties is in some way reversed in us, and while the less rational becomes supreme, the operation of the other ceases indeed, yet is not absolutely extinguished; but while the nutritive faculty is then busied with digestion during sleep, and keeps all our nature occupied with itself, the faculty of sense is neither entirely severed from it (for that cannot be separated which has once been naturally joined), nor yet can its activity revive, as it is hindered by the inaction during sleep of the organs of sense; and by the same reasoning (the mind also being united to the sensitive part of the soul) it would follow that we should say that the mind moves with the latter when it is in motion, and rests with it when it is quiescent.

8. As naturally happens with fire when it is heaped over with chaff, and no breath fans the flame—it neither consumes what lies beside it, nor is entirely quenched, but instead of flame it rises to the air through the chaff in the form of smoke; yet if it should obtain any breath of air, it turns the smoke to flame—in the same way the mind when hidden by the inaction of the senses in sleep is neither able to shine out through them, nor yet is quite extinguished, but has, so to say, a smouldering activity, operating to a certain extent, but unable to operate farther.

9. Again, as a musician, when he touches with the plectrum the slackened strings of a lyre, brings out no orderly melody (for that which is not stretched will not sound), but his hand frequently moves skilfully, bringing the plectrum to the position of the notes so far as place is concerned, yet there is no sound, except that he produces by the vibration of the strings a sort of uncertain and indistinct hum; so in sleep the mechanism of the senses being relaxed, the artist is either quite inactive, if the instrument is completely relaxed by satiety or heaviness; or will act slackly and faintly, if the instrument of the senses does not fully admit of the exercise of its art.

10. For this cause memory is confused, and foreknowledge, though rendered doubtful54    Reading ἐπιδιστάζουσα with several of Forbes’ mss. by uncertain veils, is imaged in shadows of our waking pursuits, and often indicates to us something of what is going to happen: for by its subtlety of nature the mind has some advantage, in ability to behold things, over mere corporeal grossness; yet it cannot make its meaning clear by direct methods, so that the information of the matter in hand should be plain and evident, but its declaration of the future is ambiguous and doubtful,—what those who interpret such things call an “enigma.”

11. So the butler presses the cluster for Pharaoh’s cup: so the baker seemed to carry his baskets; each supposing himself in sleep to be engaged in those services with which he was busied when awake: for the images of their customary occupations imprinted on the prescient element of their soul, gave them for a time the power of foretelling, by this sort of prophecy on the part of the mind, what should come to pass.

12. But if Daniel and Joseph and others like them were instructed by Divine power, without any confusion of perception, in the knowledge of things to come, this is nothing to the present statement; for no one would ascribe this to the power of dreams, since he will be constrained as a consequence to suppose that those Divine appearances also which took place in wakefulness were not a miraculous vision but a result of nature brought about spontaneously. As then, while all men are guided by their own minds, there are some few who are deemed worthy of evident Divine communication; so, while the imagination of sleep naturally occurs in a like and equivalent manner for all, some, not all, share by means of their dreams in some more Divine manifestation: but to all the rest even if a foreknowledge of anything does occur as a result of dreams, it occurs in the way we have spoken of.

13. And again, if the Egyptian and the Assyrian king were guided by God to the knowledge of the future, the dispensation wrought by their means is a different thing: for it was necessary that the hidden wisdom of the holy men55    “The holy men,” Joseph and Daniel, who were enabled, by the authority they obtained through their interpretation of dreams, to benefit the state. should be made known, that each of them might not pass his life without profit to the state. For how could Daniel have been known for what he was, if the soothsayers and magicians had not been unequal to the task of discovering the dream? And how could Egypt have been preserved while Joseph was shut up in prison, if his interpretation of the dream had not brought him to notice? Thus we must reckon these cases as exceptional, and not class them with common dreams.

14. But this ordinary seeing of dreams is common to all men, and arises in our fancies in different modes and forms: for either there remain, as we have said, in the reminiscent part of the soul, the echoes of daily occupations; or, as often happens, the constitution of dreams is framed with regard to such and such a condition of the body: for thus the thirsty man seems to be among springs, the man who is in need of food to be at a feast, and the young man in the heat of youthful vigour is beset by fancies corresponding to his passion.

15. I also knew another cause of the fancies of sleep, when attending one of my relations attacked by frenzy; who being annoyed by food being given him in too great quantity for his strength, kept crying out and finding fault with those who were about him for filling intestines with dung and putting them upon him: and when his body was rapidly tending to perspire he blamed those who were with him for having water ready to wet him with as he lay: and he did not cease calling out till the result showed the meaning of these complaints: for all at once a copious sweat broke out over his body, and a relaxation of the bowels explained the weight in the intestines. The same condition then which, while his sober judgment was dulled by disease, his nature underwent, being sympathetically affected by the condition of the body—not being without perception of what was amiss, but being unable clearly to express its pain, by reason of the distraction resulting from the disease—this, probably, if the intelligent principle of the soul were lulled to rest, not from infirmity but by natural sleep, might appear as a dream to one similarly situated, the breaking out of perspiration being expressed by water, and the pain occasioned by the food, by the weight of intestines.

16. This view also is taken by those skilled in medicine, that according to the differences of complaints the visions of dreams appear differently to the patients: that the visions of those of weak stomach are of one kind, those of persons suffering from injury to the cerebral membrane of another, those of persons in fevers of yet another; that those of patients suffering from bilious and from phlegmatic affections are diverse, and those again of plethoric patients, and of patients in wasting disease, are different; whence we may see that the nutritive and vegetative faculty of the soul has in it by commixture some seed of the intelligent element, which is in some sense brought into likeness to the particular state of the body, being adapted in its fancies according to the complaint which has seized upon it.

17. Moreover, most men’s dreams are conformed to the state of their character: the brave man’s fancies are of one kind, the coward’s of another; the wanton man’s dreams of one kind, the continent man’s of another; the liberal man and the avaricious man are subject to different fancies; while these fancies are nowhere framed by the intellect, but by the less rational disposition of the soul, which forms even in dreams the semblances of those things to which each is accustomed by the practice of his waking hours.

ΚΕΦΑΛΑΙΟΝ. ΙΓʹ. Περὶ ὕπνου, καὶ χάσμης, καὶ ὀνείρων, αἰτιολογία.

Ἡ ὑλικὴ καὶ ῥοώδης αὕτη τῶν σωμάτων ζωὴ, πάντοτε διὰ κινήσεως προϊοῦσα, ἐν τούτῳ ἔχει τοῦ εἶναι τὴν δύναμιν, ἐν τῷ μὴ στῆναί ποτε τῆς κινήσεως. Καθάπερ δέ τις ποταμὸς κατὰ τὴν ἰδίαν ῥέων ὁρμὴν, πλήρη μὲν δείκνυσι τὴν κοιλότητα, δι' ἧς ἂν τύχῃ φερόμενος, οὐ μὴν ἐν τῷ αὐτῷ ὕδατι περὶ τὸν αὐτὸν ἀεὶ τόπον ὁρᾶται, ἀλλὰ τὸ μὲν ὑπέδραμεν αὐτοῦ, τὸ δὲ ὑπεῤῥέει: οὕτω καὶ τὸ ὑλικὸν τῆς τῇδε ζωῆς διά τινος κινήσεως καὶ ῥοῆς τῇ συνεχείᾳ τῆς τῶν ἐναντίων διαδοχῆς ἀμείβεται, ὡς ἂν μηδέποτε στῆναι δύνασθαι τῆς μεταβολῆς, ἀλλὰ τῇ δυνάμει τοῦ ἀτρεμεῖν ἄπαυστον ἔχειν διὰ τῶν ὁμοίων ἐναμειβομένην τὴν κίνησιν. Εἰ δέ ποτε κινούμενον παύσοιτο, καὶ τοῦ εἶναι πάντως τὴν παῦλαν ἕξει: οἷον, διεδέξατο τὸ πλῆρες ἡ κένωσις, καὶ πάλιν ἀντεισῆλθεν ἡ πλήρωσις τῇ κενότητι. Ὕπνος τὸ σύντονον τῆς ἐγρηγόρσεως ὑπεχάλασεν, εἶτα ἐγρήγορσις τὸ ἀνειμένον ἐτόνωσε. Καὶ οὐδέτερον τούτων ἐν τῷ διηνεκεῖ συμμένει, ἀλλ' ὑποχωρεῖ ταῖς παρουσίαις ἀλλήλων ἀμφότερα, οὕτω τῆς φύσεως ἑαυτὴν ταῖς ὑπαλλαγαῖς ἀνακαινιζούσης, ὡς ἑκατέρων ἐν τῷ μέρει μεταλαγχάνουσαν ἀδιασπάστως ἀπὸ τοῦ ἑτέρου μεταβαίνειν ἐπὶ τὸ ἕτερον. Τό τε γὰρ διαπαντὸς συντετάσθαι ταῖς ἐνεργείαις τὸ ζῶον, ῥῆξίν τινα καὶ διασπασμὸν τῶν ὑπερτεινομένων ποιεῖται μερῶν: ἥ τε διηνεκὴς τοῦ σώματος ἄνεσις διάπτωσίν τινα τοῦ συνεστῶτος καὶ λύσιν ἐργάζεται. Τὸ δὲ κατὰ καιρὸν μετρίως ἑκατέρων ἐπιτυγχάνειν, δύναμις πρὸς διαμονήν ἐστι τῆς φύσεως, διὰ τῆς διηνεκοῦς πρὸς τὰ ἀντικείμενα μεταβάσεως ἐν ἑκατέροις ἑαυτὴν ἀπὸ τῶν ἑτέρων ἀναπαυούσης. Οὕτω τοίνυν τετονωμένον διὰ τῆς ἐγρηγόρσεως τὸ σῶμα λαβοῦσα, λύσιν ἐμποιεῖ διὰ τοῦ ὕπνου τῷ τόνῳ, τὰς αἰσθητικὰς δυνάμεις πρὸς καιρὸν ἐκ τῶν ἐνεργειῶν ἀναπαύσασα, οἷόν τινας ἵππους μετὰ τοὺς ἀγῶνας τῶν ἁρμάτων ἐκλύσασα. Ἀναγκαία δὲ τῇ συστάσει τοῦ σώματος ἡ εὔκαιρος ἄνεσις, ὡς ἂν ἀκωλύτως ἐφ' ἅπαν τὸ σῶμα διὰ τῶν ἐν αὐτῷ πόρων ἡ τροφὴ διαχέοιτο, μηδενὸς τόνου τῇ διόδῳ παρεμποδίζοντος. Καθάπερ γὰρ ἐκ τῆς διαβρόχου γῆς, ὅταν ἐπιλάμψῃ θερμοτέραις ἀκτῖσιν ὁ ἥλιος, ἀτμοί τινες ὀμιχλώδεις ἀπὸ τοῦ βάθους ἀνέλκονται: ὅμοιόν τι γίνεται καὶ ἐν τῇ καθ' ἡμᾶς γῇ, τῆς τροφῆς ἔσωθεν ὑπὸ τῆς φυσικῆς θερμότητος ἀναζεούσης. Ἀνωφερεῖς δὲ ὄντες οἱ ἀτμοὶ κατὰ φύσιν, καὶ ἀερώδεις, καὶ πρὸς τὸ ὑπερκείμενον ἀναπνέοντες, ἐν τοῖς κατὰ τὴν κεφαλὴν γίνονται χωρίοις, οἷόν τις καπνὸς εἰς ἁρμονίαν τοίχου διαδυόμενος: εἶτα ἐντεῦθεν ἐπὶ τοὺς τῶν αἰσθητηρίων πόρους ἐξατμιζόμενοι διαφοροῦνται, δι' ὧν ἀργεῖ κατ' ἀνάγκην ἡ αἴσθησις, τῇ παρόδῳ τῶν ἀτμῶν ἐκείνων ὑπεξιοῦσα. Αἱ μὲν γὰρ ὄψεις τοῖς βλεφάροις ἐπιλαμβάνονται, οἷόν τινος μηχανῆς μολυβδίνης, τοῦ τοιούτου λέγω βάρους, τοῖς ὀφθαλμοῖς ἐπιχαλώσης τὸ βλέφαρον. Παχυνθεῖσα δὲ τοῖς αὐτοῖς τούτοις ἀτμοῖς ἡ ἀκοὴ, καθάπερ θύρας τινὸς τοῖς ἀκουστικοῖς μορίοις ἐπιτεθείσης, ἡσυχίαν ἀπὸ τῆς κατὰ φύσιν ἐνεργείας ἄγει: καὶ τὸ τοιοῦτον πάθος ὕπνος ἐστὶν, ἀτρεμούσης ἐν τῷ σώματι τῆς αἰσθήσεως, καὶ παντάπασιν ἐκ τῆς κατὰ φύσιν κινήσεως ἀπρακτούσης, ὡς ἂν εὐπόρευτοι γένωνται τῆς τροφῆς αἱ ἀναδόσεις, δι' ἑκάστου τῶν πόρων τοῖς ἀτμοῖς συνδιεξιούσης.

Καὶ τούτου χάριν εἰ στενοχωροῖτο μὲν ὑπὸ τῆς ἔνδοθεν ἀναθυμιάσεως ἡ περὶ τὰ αἰσθητήρια διασκευὴ, κωλύοιτο δὲ κατά τινα χρείαν ὁ ὕπνος: πλῆρες γενόμενον τῶν ἀτμῶν τὸ νευρῶδες, αὐτὸ ὑφ' ἑαυτοῦ φυσικῶς διατείνεται, ὡς διὰ τῆς ἐκτάσεως τὸ παχυνθὲν ὑπὸ τῶν ἀτμῶν μέρος ἐκλεπτυνθῆναι: οἷόν τι ποιοῦσιν οἱ διὰ τῆς σφοδροτέρας στρεβλώσεως τὸ ὕδωρ τῶν ἱματίων ἐκθλίβοντες. Καὶ ἐπειδὴ κυκλοτερῆ τὰ περὶ τὸν φάρυγγα μέρη, πλεονάζει δὲ τὸ νευρῶδες ἐν τούτοις: ὅταν καὶ ἀπὸ τούτων ἐξωσθῆναι δέοι τὴν τῶν ἀτμῶν παχυμέρειαν (ἐπειδὴ ἀμήχανόν ἐστι δι' εὐθείας ἀποτεῖναι τὸ κυκλοειδὲς μέρος, εἰ μὴ κατὰ τὸ περιφερὲς σχῆμα διαταθείη): τούτου χάριν ἀποληφθέντος ἐν τῇ χάσμῃ τοῦ πνεύματος, ὅτε ὁ ἀνθερεὼν ἐπὶ τὸ κάτω τοῖς γαργαρεῶσιν ὑποκοιλαίνεται, καὶ τῶν ἐντὸς πάντων εἰς κύκλου σχῆμα διαταθέντων, ἡ λιγνυώδης ἐκείνη παχύτης ἡ ἐναπειλημμένη τοῖς μέρεσι συνδιαπνεῖται τῇ διεξόδῳ τοῦ πνεύματος. Πολλάκις δὲ, καὶ μετὰ τὸν ὕπνον οἶδε τὸ τοιοῦτον συμβαίνειν, ὅταν τι τῶν ἀτμῶν ἐκείνων περιλειφθείη τοῖς τόποις ἄπεμπτόν τε καὶ ἀδιάπνευστον. Ἐκ τούτων τοίνυν ὁ ἀνθρώπινος νοῦς δείκνυσιν ἐναργῶς, ὅτι τῆς φύσεως ἔχεται, συνεστώσης μὲν καὶ ἐγρηγορυίας, καὶ αὐτὸς συνεργῶν καὶ κινούμενος: παρεθείσης δὲ τῷ ὕπνῳ, μένων ἀκίνητος, εἰ μή τις ἄρα τὴν ὀνειρώδη φαντασίαν νοῦ κίνησιν ὑπολάβοι κατὰ τὸν ὕπνον ἐνεργουμένην. Ἡμεῖς δέ φαμεν μόνην δεῖν τὴν ἔμφρονά τε καὶ συνεστῶσαν τῆς διανοίας ἐνέργειαν ἐπὶ τὸν νοῦν ἀναφέρειν: τὰς δὲ κατὰ τὸν ὕπνον φαντασιώδεις φλυαρίας ἰνδάλματά τινα τῆς κατὰ τὸν νοῦν ἐνεργείας οἰόμεθα τῷ ἀλογωτέρῳ τῆς ψυχῆς εἴδει κατὰ τὸ συμβὰν διαπλάττεσθαι. Τῶν γὰρ αἰσθήσεων τὴν ψυχὴν ἀπολυθεῖσαν διὰ τοῦ ὕπνου, καὶ τῶν κατὰ νοῦν ἐνεργειῶν ἐκτὸς εἶναι κατ' ἀνάγκην συμβαίνει. Διὰ γὰρ τούτων πρὸς τὸν ἄνθρωπον ἡ τοῦ νοῦ συνανάκρασις γίνεται: τῶν οὖν αἰσθήσεων παυσαμένων, ἀργεῖν ἀνάγκη καὶ τὴν διάνοιαν. Τεκμήριον δὲ τὸ καὶ ἐν ἀτόποις καὶ ἐν ἀμηχάνοις πολλάκις δοκεῖν εἶναι τὸν φανταζόμενον: ὅπερ οὐκ ἂν ἐγένετο, λογισμῷ καὶ διανοίᾳ τῆς ψυχῆς τηνικαῦτα διοικουμένης. Ἀλλά μοι δοκεῖ ταῖς προτιμοτέραις τῶν δυνάμεων τῆς ψυχῆς ἠρεμούσης (φημὶ δὲ ταῖς κατὰ τὸν νοῦν καὶ τὴν αἴσθησιν ἐνεργείαις) μόνον τὸ θρεπτικὸν αὐτῆς μέρος ἐνεργὸν κατὰ τὸν ὕπνον εἶναι, ἐν δὲ τούτῳ τῶν καθ' ὕπαρ γενομένων εἴδωλά τινα, καὶ ἀπηχήματα τῶν τε κατ' αἴσθησιν, καὶ τῶν κατὰ διάνοιαν ἐνεργουμένων, ἅπερ αὐτῷ διὰ τοῦ μνημονευτικοῦ τῆς ψυχῆς εἴδους ἐνετυπώθη: ταῦτα καθὼς ἔτυχεν ἀναζωγραφεῖσθαι, ἀπηχήματός τινος μνημονικοῦ τῷ τοιούτῳ εἴδει τῆς ψυχῆς παραμείναντος.

Ἐν τούτοις οὖν φαντασιοῦται ὁ ἄνθρωπος, οὐχ εἱρμῷ τινι πρὸς τὴν τῶν φαινομένων ὁμιλίαν ἀγόμενος, ἀλλὰ πεφυρμέναις τισὶ καὶ ἀνακολούθοις ἀπάταις περιπλανώμενος. Καθάπερ δὲ κατὰ τὰς σωματικὰς ἐνεργείας, τῶν μερῶν ἰδιαζόντως τι κατὰ τὴν ἐγκειμένην αὐτῷ φυσικῶς δύναμιν ἐνεργοῦντος, γίνεταί τις καὶ τοῦ ἠρεμοῦντος μέρους πρὸς τὸ κινούμενον συνδιάθεσις: ἀναλόγως καὶ ἐπὶ τῆς ψυχῆς, κἂν τὸ μὲν αὐτῆς ἠρεμοῦν, τὸ δὲ κινούμενον τύχῃ, τὸ ὅλον τῷ μέρει συνδιατίθεται. Οὐδὲ γὰρ ἐνδέχεται συνδιασπασθῆναι πάντη τὴν κατὰ φύσιν ἑνότητα, κρατούσης ἐν μέρει τινὸς τῶν κατ' αὐτὴν δυνάμεων διὰ τῆς ἐνεργείας. Ἀλλ' ὥσπερ ἐγρηγορότων τε καὶ σπουδαζόντων ἐπικρατεῖ μὲν ὁ νοῦς, ὑπηρετεῖ δὲ ἡ αἴσθησις, οὐκ ἀπολείπεται δὲ τούτων ἡ διοικητικὴ τοῦ σώματος δύναμις (ὁ μὲν γὰρ νοῦς πορίζει τὴν τροφὴν τῇ χρείᾳ, ἡ δὲ αἴσθησις τὸ πορισθὲν ὑπεδέξατο, ἡ δὲ θρεπτικὴ τοῦ σώματος δύναμις ἑαυτῇ τὸ δοθὲν προσῳκείωσεν): οὕτω καὶ κατὰ τὸν ὕπνον ἀντιμεθίσταταί πως ἐν ἡμῖν ἡ τῶν δυνάμεων τούτων ἡγεμονία: καὶ κρατοῦντος τοῦ ἀλογωτέρου, παύεται μὲν ἡ τῶν ἑτέρων ἐνέργεια, οὐ μὴν παντελῶς ἀποσβέννυται. Ἐπειγομένης δὲ τηνικαῦτα διὰ τοῦ ὕπνου πρὸς τὴν πέψιν τῆς θρεπτικῆς δυνάμεως, καὶ πᾶσαν τὴν φύσιν πρὸς ἑαυτὴν ἀσχολούσης, οὔτε παντελῶς διασπᾶται ταύτης ἡ κατ' αἴσθησιν δύναμις (οὐ γὰρ ἐνδέχεται τὸ ἅπαξ συμπεφυκὸς διατέμνεσθαι), οὔτε ἀναλάμπειν ἡ αὐτῆς ἐνέργεια δύναται, τῇ τῶν αἰσθητηρίων ἀργίᾳ κατὰ τὸν ὕπνον ἐμπεδηθεῖσα. Κατὰ τὸν αὐτὸν δὲ λόγον καὶ τοῦ νοῦ πρὸς τὸ αἰσθητικὸν εἶδος τῆς ψυχῆς οἰκειουμένου, ἀκόλουθον ἂν εἴη καὶ κινουμένου τούτου, συγκινεῖσθαι λέγειν αὐτὸν, καὶ ἠρεμοῦντος συγκαταπαύεσθαι. Οἷον δέ τι περὶ τὸ πῦρ γίνεσθαι πέφυκεν, ὅταν μὲν ὑποκρυφθῇ τοῖς ἀχύροις ἁπανταχόθεν, μηδεμιᾶς ἀναπνοῆς ἀναῤῥιπιζούσης τὴν φλόγα, οὔτε τὰ προσπαρακείμενα νέμεται, οὔτε παντελῶς κατασβέννυται, ἀλλ' ἀντὶ φλογὸς ἀτμός τις διὰ τῶν ἀχύρων ἐπὶ τὸν ἀέρα διέξεισιν, εἰ δέ τινος λάβοιτο διαπνοῆς, φλόγα τὸν καπνὸν ἀπεργάζεται: τὸν αὐτὸν τρόπον καὶ ὁ νοῦς τῇ ἀπραξίᾳ τῶν αἰσθήσεων κατὰ τὸν ὕπνον συγκαλυφθεὶς, οὔτε ἐκλάμπειν δι' αὐτῶν δυνατῶς ἔχει, οὔτε μὴν παντελῶς κατασβέννυται: ἀλλ' οἷον καπνοειδῶς κινεῖται, τὸ μέν τι ἐνεργῶν, τὸ δὲ οὐ δυνάμενος. Καὶ ὥσπερ τις μουσικὸς κεχαλασμέναις ταῖς χορδαῖς τῆς λύρας ἐμβαλὼν τὸ πλῆκτρον, οὐ κατὰ ῥυθμὸν προάγει τὸ μέλος: οὐ γὰρ ἂν τὸ μὴ συντεταμένον ἠχήσειεν: ἀλλ' ἡ μὲν χεὶρ τεχνικῶς πολλάκις κινεῖται, πρὸς τὴν τοπικὴν θέσιν τῶν τόνων τὸ πλῆκτρον ἄγουσα, τὸ δὲ ἠχοῦν οὐκ ἔστιν, εἰ μὴ ὅσον ἄσημόν τινα καὶ ἀσύντακτον ἐν τῇ κινήσει τῶν χορδῶν ὑπηχεῖ τὸν βόμβον: οὕτω διὰ τοῦ ὕπνου τῆς ὀργανικῆς τῶν αἰσθητηρίων κατασκευῆς χαλασθείσης, ἢ καθόλου ἠρεμεῖ ὁ τεχνίτης, εἴπερ τελείαν λύσιν ἐκ πληθώρας τινὸς καὶ βάρους πάθοι τὸ ὄργανον, ἢ ἀτόνως τε καὶ ἀμυδρῶς ἐνεργήσει, οὐχ ὑποδεχομένου τοῦ αἰσθητικοῦ ὀργάνου δι' ἀκριβείας τὴν τέχνην. Διὰ τοῦτο ἤ τε μνήμη συγκεχυμένη, καὶ ἡ πρόγνωσις προκαλύμμασί τισιν ἀμφιβόλοις ἐπινυστάζουσα, ἐν εἰδώλοις τῶν καθ' ὕπαρ σπουδαζομένων φαντασιοῦται, καί τι τῶν ἐκβαινόντων πολλάκις ἐμήνυσε. Τῷ γὰρ λεπτῷ τῆς φύσεως, ἔχει τι πλέον παρὰ τὴν σωματικὴν παχυμέρειαν εἰς τὸ καθορᾷν τι τῶν ὄντων δύνασθαι. Οὐ μὴν δι' εὐθείας τινὸς δύναται διασαφεῖν τὸ λεγόμενον, ὡς τηλαυγῆ τε καὶ πρόδηλον εἶναι τὴν τῶν προκειμένων διδασκαλίαν: ἀλλὰ λοξὴ καὶ ἀμφίβολος τοῦ μέλλοντος ἡ δήλωσις γίνεται, ὅπερ αἴνιγμα λέγουσιν οἱ τὰ τοιαῦτα ὑποκρινόμενοι. Οὕτως ὁ οἰνοχόος ἐκθλίβει τὴν βότρυν τῇ κύλικι τοῦ Φαραώ: οὕτω κανηφορεῖν ὁ σιτοποιὸς ἐφαντάσθη, ἐν οἷς καθ' ὕπαρ ἑκάτερος τὴν σπουδὴν εἶχεν, ἐν τούτοις εἶναι καὶ διὰ τῶν ὀνείρων οἰόμενος. Τῶν γὰρ συνήθων αὐτοῖς ἐπιτηδευμάτων τὰ εἴδωλα τῷ προγνωστικῷ τῆς ψυχῆς ἐντυπωθέντα, παρέσχεν ἐπὶ καιροῦ τῶν ἐκβησομένων διὰ τῆς τοιαύτης τοῦ νοῦ προφητείας καταμαντεύσασθαι.

Εἰ δὲ Δανιὴλ καὶ Ἰωσὴφ, καὶ οἱ κατ' ἐκείνους θείᾳ δυνάμει, μηδεμιᾶς αὐτοὺς ἐπιθολούσης αἰσθήσεως, τὴν τῶν μελλόντων γνῶσιν προεπαιδεύοντο, οὐδὲν τοῦτο πρὸς τὸν προκείμενον λόγον. Οὐδὲ γὰρ ἄν τις ταῦτα τῇ δυνάμει τῶν ἐνυπνίων λογίσαιτο, ἐπεὶ πάντως ἐκ τοῦ ἀκολούθου καὶ τὰς καθ' ὕπαρ γινομένας θεοφανείας οὐκ ὀπτασίαν, ἀλλὰ φύσεως ἀκολουθίαν κατὰ τὸ αὐτόματον ἐνεργουμένην οἰήσεται. Ὥσπερ τοίνυν πάντων ἀνθρώπων κατὰ τὸν ἴδιον νοῦν διοικουμένων, ὀλίγοι τινές εἰσιν οἱ τῆς θείας ὁμιλίας ἐκ τοῦ ἐμφανοῦς ἀξιούμενοι: οὕτω κοινῶς πᾶσι καὶ ὁμοτίμως τῆς ἐν ὕπνοις φαντασίας κατὰ φύσιν ἐγγινομένης, μετέχουσί τινες, οὐχὶ πάντες, θειοτέρας τινὸς διὰ τῶν ὀνείρων τῆς ἐμφανείας. Τοῖς δ' ἄλλοις πᾶσι κἂν γένηταί τις ἐξ ἐνυπνίων περί τι πρόγνωσις, κατὰ τὸν εἰρημένον γίνεται τρόπον. Εἰ δὲ καὶ ὁ Αἰγύπτιος καὶ ὁ Ἀσσύριος τύραννος θεόθεν πρὸς τὴν τῶν μελλόντων ὡδηγοῦντο γνῶσιν, ἑτερόν ἐστι τὸ διὰ τούτων οἰκονομούμενον: φανερωθῆναι γὰρ ἔδει κεκρυμμένην τὴν τῶν ἁγίων σοφίαν, ὡς ἂν μὴ ἄχρηστος τῷ κοινῷ παραδράμῃ τὸν βίον. Πῶς γὰρ ἐγνώσθη τοιοῦτος ὢν Δανιὴλ, μὴ τῶν ἐπαοιδῶν καὶ μάγων πρὸς τὴν εὕρεσιν τῆς φαντασίας ἀτονησάντων, Πῶς δ' ἂν περιεσώθη τὸ Αἰγύπτιον ἔθνος, ἐν δεσμωτηρίῳ καθειργμένου τοῦ Ἰωσὴφ, εἰ μὴ παρήγαγεν εἰς μέσους αὐτὸν ἡ τοῦ ἐνυπνίου κρίσις; Οὐκοῦν ἄλλο τι ταῦτα, καὶ οὐχὶ κατὰ τὰς κοινὰς φαντασίας λογίζεσθαι χρή. Ἡ δὲ συνήθης αὕτη τῶν ὀνείρων ὄψις κοινὴ πάντων ἐστὶ, πολυτρόπως καὶ πολυειδῶς ταῖς φαντασίαις ἐγγινομένη. Ἢ γὰρ παραμένει, καθὼς εἴρηται, τῷ μνημονικῷ τῆς ψυχῆς τῶν μεθημερινῶν ἐπιτηδευμάτων τὰ ἀπηχήματα: ἡ πολλάκις καὶ πρὸς τὰς ποιὰς τοῦ σώματος διαθέσεις ἡ τῶν ἐνυπνίων κατάστασις ἀνατυποῦται. Οὕτω γὰρ ὁ διψώδης ἐν πηγαῖς εἶναι δοκεῖ, καὶ ἐν εὐωχίαις ὁ τροφῆς προσδεόμενος, καὶ ὁ νέος, σφριγώσης αὐτῷ τῆς ἡλικίας, καταλλήλῳ τῷ πάθει φαντασιοῦται. Ἔγνων δὲ καὶ ἄλλην ἐγὼ τῶν καθ' ὕπνου γενομένων αἰτίαν, θεραπεύων τινὰ τῶν ἐπιτηδείων ἑαλωκότα φρενίτιδι, ὃς βαρούμενος τῇ τροφῇ πλείονι τῆς δυνάμεως αὐτοῦ προσενεχθείσῃ, ἐβόα, τοὺς περιεστῶτας μεμφόμενος, ὅτι ἔντερα κόπρου πληρώσαντες εἶεν ἐπιτεθεικότες αὐτῷ.

Καὶ ἤδη τοῦ σώματος αὐτῷ πρὸς ἱδρῶτα σπεύδοντος, ᾐτιᾶτο τοὺς παρόντας ὕδωρ ἔχειν ἡτοιμασμένον, ἐφ' ᾧ τε καταβρέξαι κείμενον, καὶ οὐκ ἐνεδίδου βοῶν, ἕως ἡ ἔκβασις τῶν τοιούτων μέμψεων τὰς αἰτίας ἡρμήνευσεν. Ἀθρόως γὰρ ἱδρώς τε πολὺς ἐπεῤῥύη τῷ σώματι, καὶ ἡ γαστὴρ ὑποφθαρεῖσα τὴν ἐν τοῖς ἐντέροις βαρύτητα διεσήμανεν. Ὅπερ τοίνυν, ἀμβλυνθείσης ὑπὸ τῆς νόσου τῆς νήψεως, ἔπασχεν ἡ φύσις συνδιατιθεμένη τῷ πάθει τοῦ σώματος, τοῦ μὲν ὀχλοῦντος οὐκ ἀναισθήτως ἔχουσα, διασαφῆναι δὲ τὸ λυποῦν ἐναργῶς, διὰ τὴν ἐκ τῆς νόσου παραφορὰν, οὐκ ἰσχύουσα: τοῦτο κατὰ τὸ εἰκὸς, εἰ μὴ ἐξ ἀῤῥωστίας, ἀλλὰ τῷ κατὰ φύσιν ὕπνῳ τὸ διανοητικὸν τῆς ψυχῆς κατηυνάσθη, ἐνύπνιον ἂν τῷ οὕτως διακειμένῳ ἐγίνετο, ὕδατι μὲν τῆς τοῦ ἱδρῶτος ἐπιῤῥοῆς, ἐντέρων δὲ βάρει τῆς κατὰ τὴν τροφὴν ἀχθηδόνος σημαινομένης. Τοῦτο καὶ πολλοῖς τῶν τὴν ἰατρικὴν πεπαιδευμένων δοκεῖ, παρὰ τὰς τῶν παθημάτων διαφορὰς, καὶ τὰς τῶν ἐνυπνίων ὄψεις τοῖς κάμνουσι γίνεσθαι; ἄλλας μὲν τῶν στομαχούντων, ἑτέρας δὲ τῶν κεκακωμένων τὰς μήνιγγας, καὶ τῶν ἐν πυρετοῖς πάλιν ἑτέρας, τῶν τε κατὰ χολὴν, καὶ τῶν ἐν φλέγματι κακουμένων οὐ τὰς αὐτὰς, καὶ τῶν πληθωρικῶν, καὶ τῶν ἐκτετηκότων πάλιν ἄλλας. Ἐξ ὧν ἔστιν ἰδεῖν, ὅτι ἡ θρεπτική τε καὶ αὐξητικὴ δύναμις τῆς ψυχῆς ἔχῃ τι καὶ τοῦ νοεροῦ συγκατεσπαρμένον αὐτῇ διὰ τῆς ἀνακράσεως, ὁ τῇ ποιᾷ διαθέσει τοῦ σώματος τρόπον τινὰ ἐξομοιοῦται, καὶ τὸ ἐπικρατοῦν πάθος ταῖς φαντασίαις μεθαρμοζόμενον. Ἔτι δὲ καὶ πρὸς τὰς τῶν ἠθῶν καταστάσεις τυποῦται πολλοῖς τὰ ἐνύπνια. Ἄλλα τοῦ ἀνδρείου, καὶ ἄλλα τοῦ δειλοῦ τὰ φαντάσματα: ἄλλοι τοῦ ἀκολάστου ὄνειροι, καὶ ἄλλοι τοῦ σώφρονος: ἐν ἑτέροις ὁ μεταδοτικὸς, καὶ ἐν ἑτέροις φαντασιοῦται ὁ ἄπληστος, οὐδαμοῦ τῆς διανοίας, ἀλλὰ τῆς ἀλογωτέρας διαθέσεως ἐν τῇ ψυχῇ τὰς τοιαύτας φαντασίας ἀνατυπούσης οἷς προειθίσθη διὰ τῆς καθ' ὕπαρ μελέτης, τούτων τὰς εἰκόνας καὶ ἐν τοῖς ἐνυπνίοις ἀναπλαττούσης.