There are many examples of phenomena reminiscent of self-hypnosis in classical literature. It is well-known, for instance, that the philosopher Socrates had a tendency to enter spontaneous cataleptic trances, in which he was gripped by contemplation of his inner psyche (nous). The best account of this is found in Plato's Symposium where Socrates freezes in deep meditation en route to a drinking party (the 'symposium' of the title). The host Agathon, and the other guests, are left waiting; a slave is sent and returns reporting:

"Socrates is here, but he's gone off to the neighbour's porch. He's standing there and won't come in even though I called him several times."

Agathon gives the order, "Go back and bring him in!" but Socrates' companion, Aristodemus, objects:

"No, no, leave him alone. It's one of his habits: every now and then he just goes off like that and stands frozen, wherever he happens to be."

Socrates eventually arrives when the meal is halfway finished, at which Agathon chides him:

"Socrates, come lie down next to me. Who knows, if I touch you, I may catch a bit of the enlightenment (sophia) that came to you under my neighbour's porch. It's clear you've seen the light. If you hadn't you'd still be standing there!"

Toward the end of the symposium, the drunken Alcibiades arrives, a notorious playboy who idolises and is in love with Socrates. He begins a speech singing the praises of his beloved mentor, describing how the middle-aged Socrates exhibited surprising sexual restraint by continually spurning his advances, even when he went so far as slipping naked into bed with him. Alcibiades was at this time a youth, famous for his beauty. Socrates, by contrast, was notoriously ugly, balding, and pot-bellied –the Greeks described him as looking like a torpedo fish!

Alcibiades continues by describing various events which he observed during their military service together, when Athens invaded Potidaea. During this campaign Socrates was awarded the 'prize of pre-eminent valour', which he declined in preference that it should belong to Alcibiades.

Despite his age, Socrates appeared to be hardier and tougher than any other soldier. He walked barefoot on ice, and in bitter cold wore only the customary grey, light cotton cloak of the ancient philosophers. When supplies were lost he seemed impervious to hunger. He wasn't partial to drink, but he could drink any man under the table, seemingly unaffected by alcohol. We are also told that several times when Athens was rife with plague, Socrates was the only citizen unaffected by illness.

Socrates was, in earlier years, a man of physical prowess, and fearless during the thick of combat; the ancient historian of philosophy, Diogenes Laertius, reports his rescue of the soldier and author Xenophon, who later became his disciple and founded one of ten distinct 'Socratic' sects in Athens,

He paid great attention also to the training of the body, and was always in excellent condition himself. Accordingly, he joined in the expedition to Amphipolis, and he it was who took up and saved Xenophon in the battle of Delian, when he had fallen from his horse; for when all the Athenians had fled, he retreated quietly, turning round slowly, and watching to repel any one who attacked him.

Alcibiades seems to be referring to this incident when he remarks,

"…in the midst of battle he was making his way exactly as he does around town, 'with swaggering gait and roving eye.' He was observing everything quite calmly, looking out for friendly troops and keeping an eye on the enemy. Even from a great distance it was obvious that this was a very brave man, who would put up a terrific fight if anyone approached him."

These are examples of the exceptional physical and emotional self-mastery (enkrateia) attributed to many classical philosophers. (What a contrast with modern academics!) Alcibiades deliberately links this discussion of Socrates' self-control to a further example of his deep meditative trances:

"So much for that! But you should hear what else he did during that same campaign, 'The exploit our strong-hearted hero dared to do.' One day, at dawn, he started thinking about some problem or other; he just stood outside, trying to figure it out. He couldn't resolve it, but he wouldn't give up. He simply stood there, glued to the same spot. By midday, many soldiers had seen him, and, quite mystified, they told everyone that Socrates had been standing there all day, thinking about something. He was still there when evening came, and after dinner some Ionians moved their bedding outside, where it was cooler and more comfortable (all this took place in the summer), but mainly in order to watch if Socrates was going to stay out there all night. And so he did; he stood in the very same spot until dawn! He only left next morning, when the Sun came out, and he made his prayers to the new day."

Hence, just as on his way to Agathon's symposium, Socrates is described as entering a mystical, cataleptic trance. The difference is that the trance described by Alcibiades appears to have lasted an entire 24 hours, during which extraordinary length of time Socrates remained physically immobile and impervious to his surroundings and the heat of the Mediterranean summer Sun.

It's reasonable to say, therefore, that Socrates provides one of the earliest and most influential examples of meditative trance recorded in European literature. There are, however, no indications in the writings of Plato or Xenophon (our two main sources for information on him) that these trances were considered similar to sleep, the main factor which would justify us in drawing the analogy with self-hypnosis. Nevertheless, subsequent references to the tradition in which Socrates stood do make this explicit connection. An important reference to 'sleep-trances' relates to the Bacchae, the followers of Dionysus, the very god to whom Plato's Symposium is dedicated. Socrates himself is often considered to have been an initiate of the Orphic mystery religion, a mystical movement which evolved out of the rites of the Bacchae. The great James Braid, in the first book ever written on hypnotism (as opposed to Animal Magnetism), cites a quotation from the Roman poet Horace (c. 65 BC), 'Exsomnis stupet Euhias' (Odes 3:25), which according to Braid's translation, describes the entranced Bacchae as being possessed by a 'stupor different from common sleep.' This remark indicates that the followers of Dionysus were known to experience trance states similar to sleep but distinct from normal, nocturnal sleep.

In a critical text (c. 300 A.D.) on the subject of 'theurgy' the ancient study of spiritual rituals and ceremonies, the Neoplatonic philosopher Porphyry discusses many examples of trance states in the Mystery religions and Platonic philosophical practices. In one revealing passage, he refers to the use of imagination (i.e., suggestion) in conjunction with a variety of practical props and techniques (including eye-fixation) as a means to entering trance states:

Others who understand themselves in other respects become divinely inspired through the imagination: some taking darkness as accessory, others employing certain potions, and others depending on singing and magic figures. Some are affected by means of water, others by gazing on a wall, others by the hypæthral air, and others by the sun or some other of the heavenly luminaries. (Iamblichus, Theurgy: On the Mysteries of Egypt, 3: 8)

A more detailed account of the experience of hypnotic-sleep, presumably brought about by these or similar methods, occurs in the Poimandres of Hermes Trismegistus (c. 150 A.D.), a Graeco-Egyptian mystical text which uses the language of Platonic philosophy derived from Socrates. The legendary Egyptian philosopher Hermes begins by reporting the experience of a sleep-like trance during which he contemplates archetypes, or philosophical 'essences':

"Once, when my mind had become intent on the things-which-are [a Socratic term for archetypes], and my innermost mind [nous] was raised to a great height, while my bodily senses were withdrawn as in sleep [hypnos] (when men are weighed down by too much food or by the fatigue of the body) it seemed that someone immensely great of infinite dimensions happened to call my name […]'

This 'someone' is revealed to be God, in the form of 'Cosmic Nous.' In Greek mysticism, the innermost level of the individual self (nous) is generally assumed to be one with the 'Cosmic Self', i.e., the mind of God himself (Nous, capitalised). (This is effectively the 'archetypal Self' of Jungian psychology.) Hermes proceeds to give a lengthy and detailed account of his conversation with God/Nous. In conclusion he describes the nature of sleep-trance in a passage absolutely loaded with technical terminology from ancient Dionysian mysticism and Socratic/Platonic philosophy:

'For the sleep [hypnos] of the body, became the awakening of the mind [psyche], the closing of the eyes became true vision, my silence became pregnant with the Supreme Good, and the utterance of the Word [Logos] became the generation of riches.'

This curious statement, that "The sleep of the body became the awakening of the mind," provides us with a perfect and concise description of classical hypnotic-meditation. The rest of this final sentence emphasises that through passively withdrawing the sense of vision and the activity of speech Hermes' mind was illuminated with vision and speech from an unconscious source. In this case, by contemplating the archetypal essence of his own individual self, Hermes' reports that he experienced contact with an image of the 'Higher Self' (Nous). This report is clearly inspired by Socrates' remarks elsewhere on the aims of meditation and philosophy: to experience a vision of the archetypes.

Nowadays, many people deny any neuro-psychological similarity between hypnosis and sleep. However, one of the most striking features of classical hypnosis has always been the fact that it superficially, or externally, resembles sleep. It is for this reason that the Marquis de Puysegur described hypnosis as 'artificial somnambulism', Deleuze described it as 'lucid sleep', and Braid as 'nervous sleep' (i.e., sleep of the nervous system). These are all crude attempts to define hypnosis as a trance "different from normal sleep," i.e., as a merely physical, mentally lucid, and artificial form of sleep. These descriptions are all highly consistent with the Neoplatonic experience of a 'sleep of the body' which is nevertheless an 'awakening of the mind.' Whether this is the same hypnotic-meditation ('a stupor different from common sleep') attributed to the Bacchae, we will probably never know for certain. Hermes, on the other hand, does describe it in terms which sound very similar to the cataleptic trances of Socrates, and it is clearly intended to stand in the same philosophical tradition.

Braid himself was apparently unaware of these links to Socrates and Neoplatonism, however, he rightly guessed that the Greeks had experience of something akin to hypnotism. He believed, in fact, that the ancient Greek sculptors worked upon hypnotised subjects in order to achieve such startling representations of the static human form. If Braid had further investigated the tantalising references to such 'sleep-trances' in Greek literature, it could have transformed modern hypnotism. Although we know little of their practical exercises, the ancient philosophers left us extensive theoretical writings on their mystical trancework. I would like to believe that the beautiful and sophisticated metaphysics of trance found in writers of the Greek philosophical tradition may yet provide a comprehensive framework for the development of a genuine 'philosophy of hypnosis.'