Appendix I

 

Two other, less effective aids to visionary experience deserve mention - carbon dioxide and the stroboscopic lamp.  A mixture (completely non-toxic) of seven parts of oxygen and three of carbon dioxide produces, in those who inhale it, certain physical and psychological changes, which have been exhaustively described by Meduna.  Among these changes the most important, in our present context, is a marked enhancement of the ability to 'see things', when the eyes are closed.  In some cases only swirls of patterned colour are seen.  In others, there may be vivid recalls of past experiences.  (Hence the value of CO2 as a therapeutic agent.)  In yet other cases, carbon dioxide transports the subject to the Other World at the antipodes of his everyday consciousness, unconnected with his own personal history or with the problems of the human race in general.

      In the light of these facts, it becomes easy to understand the rationale of yogic breathing exercises.  Practised systematically, these exercises result, after a time, in prolonged suspensions of breath.  Long suspensions of breath lead to a high concentration of carbon dioxide in the lungs and blood, and this increase in the concentration of CO2 lowers the efficiency of the brain as a reducing valve and permits the entry into consciousness of experiences, visionary or mystical, from 'out there'.

      Prolonged and continuous shouting or singing may produce similar, but less strongly marked, results.  Unless they are highly trained, singers tend to breathe out more than they breathe in.  Consequently the concentration of carbon dioxide in the alveolar air and the blood is increased and, the efficiency of the cerebral reducing valve being lowered, visionary experience becomes possible.  Hence the interminable 'vain repetitions' of magic and religion.  The chanting of the curandero, the medicine-man, the shaman; the endless psalm-singing and sutra-intoning of Christian and Buddhist monks; the shouting and howling, hour after hour, of revivalists - under all the diversities of theological belief and aesthetic convention, the psychochemico-physiological intention remains constant.  To increase the concentration of CO2 in the lungs and blood and so to lower the efficiency of the cerebral reducing valve, until it will admit biologically useless material from Mind-at-Large - this, though the shouters, singers, and mutterers did not know it, has been at all times the real purpose and point of magic spells, of mantras, litanies, psalms, and sutras.  'The heart,' said Pascal, 'has its reasons.'  Still more cogent and much harder to unravel are the reasons of the lungs, the blood, and the enzymes, of neurones and synapses.  The way to the superconscious is through the subconscious, and the way, or at least one of the ways, to the subconscious is through the chemistry of individual cells.

      With the stroboscopic lamp we descend from chemistry to the still more elementary realm of physics.  Its rhythmically flashing light seems to act directly, through the optic nerves, on the electrical manifestations of the brain's activity.  (For this reason there is always a slight danger involved in the use of the stroboscopic lamp.  Some persons suffer from petit mal without being made aware of the fact by any clear-cut and unmistakable symptoms.  Exposed to a stroboscopic lamp, such persons may go into a full-blown epileptic fit.  The risk is not very great; but it must always be recognized.  One case in eighty may turn out badly.)

      To sit, with eyes closed, in front of a stroboscopic lamp is a very curious and fascinating experience.  No sooner is the lamp turned on than the most brilliantly coloured patterns make themselves visible.  These patterns are not static, but change incessantly.  Their prevailing colour is a function of the stroboscope's rate of discharge.  When the lamp is flashing at any speed between ten to fourteen or fifteen times a second, the patterns are prevailingly orange and red.  Green and blue make their appearance when the rate exceeds fifteen flashes a second.  After eighteen or nineteen, the patterns become white and grey.  Precisely why we should see such patterns under the stroboscope is not know.  The most obvious explanation would be in terms of the interference of two or more rhythms - the rhythm of the lamp and the various rhythms of the brain's electrical activity.  Such interferences may be translated by the visual centre and optic nerves into something, of which the mind becomes conscious as a coloured, moving pattern.  Far more difficult to explain is the fact, independently observed by several experimenters, that the stroboscope tends to enrich and intensify the visions induced by mescalin or lysergic acid [diethylamide].  Here, for example, is a case communicated to me by a medical friend.  He had taken LSD and was seeing, with his eyes shut, only coloured, moving patterns.  Then he sat down in front of a stroboscope.  The lamp was turned on and, immediately, abstract geometry was transformed into what my friend described as 'Japanese landscapes' of surpassing beauty.  But how on earth can the interference of two rhythms produce an arrangement of electrical impulses interpretable as a living, self-modulating Japanese landscape unlike anything the subject has ever seen, suffused with preternatural light and colour, and charged with preternatural significance?

      This mystery is merely a particular case of a large, more comprehensive mystery - the nature of the relations between visionary experience and events on the cellular, chemical, and electrical levels.  By touching certain areas of the brain with a very fine electrode, Penfield has been able to induce the recall of a long chain of memories relating to some past experience.  This recall is not merely accurate on every perceptual detail; it is also accompanied by all the emotions which were aroused by the events when they originally occurred.  The patient, who is under a local anaesthetic, finds himself simultaneously in two times and places - in the operating room, now, and in his childhood home, hundreds of miles away and thousands of days in the past.  Is there, one wonders, some area in the brain from which the probing electrode could elicit Blake's Cherubim, or Weir Mitchell's self-transforming Gothic tower encrusted with living gems, or my friend's unspeakably lovely Japanese landscapes?  And if, as I myself believe, visionary experiences enter our consciousness from somewhere 'out there' in the infinity of Mind-at-Large, what sort of an ad hoc neurological pattern is created for them by the receiving and transmitting brain?  And what happens to this ad hoc pattern when the vision is over?  Why do all visionaries insist on the impossibility of recalling, in anything even faintly resembling its original form and intensity, their transfiguring experiences?  How many questions - and, as yet, how few answers!