20 / CHRONICLESnof the spirit; what we see as the flow of time is anconsequence of our spirits’ flight through time. When wenconsider the external world as a four-dimensional proposition,nthen time’s flow and associated conventions, such asnpast, present, and future, evaporate. (No criticism of humble,nand often easily dismissed, convention is intended.nRather, it is suggested that convention is the stuff of life.)nMathematician Hermann Weyl described the fourdimensionalnsituation as follows: “The objective worldnsimply is, it does not happen. Only to the gaze of mynconsciousness, crawling upward along the life line of mynbody, does a section of this world come to life as a fleetingnimage in space which continuously changes in time.”nThis seems a little unreal, but, nonetheless, it is anninescapable implication of the way space and time gontogether. Weyl’s use of the word “crawling,” however, maynbe questioned on grounds of insufficient dynamism. If onensecond is the time equivalent of 186,000 miles of distance,nthen evidenfly the mind doesn’t crawl through time, butnmoves along lickety-split.nNeither Weyl nor science were the first to see life thisnway. “Man springs out of nothing, crosses time, andndisappears forever in the bosom of God” was Tocqueville’snview of life. And Rilke said: “L’avenir est fixe, chernMonsieur Kappus, c’est nous qui sommes toujours ennmouvement dans I’espace infini.” He wrote this in 1904 —nfour years before Minkowski’s 1908 lecture identifying timenas the fourth dimension and 22 years before Weyl’snwritings — so, although Rilke’s words are astonishingly similarnto Weyl’s, they are a poet’s independent statement rathernthan an echo of science’s nascent rumblings of discovery.nAlthough the notion that “the objective world simply is, itndoes not happen,” has a hard strangeness, its implicationnthat the flow of time is much more subjective than objectivenis not so strange when we think about it.nUndoubtedly our experience of time takes place onnmultiple levels. A biological clock must be a foundationnstone and very likely our mind is able to read this clocknbetter than is generally supposed. Many people know thenexperience of wanting to wake up in the morning at ancertain time, but, for some reason, not being able to use annalarm clock. “I must wake up at 7:00,” they say tonthemselves before going to sleep, and come the morning,npresto, they wake up within a couple of minutes of 7:00. Butnthe flow of time is much more than a matter of biologicalnclocks. At the mind’s higher levels, where life is actuallynlived, where we love and hate, have successes and failures,nthe flow of time becomes a very subjective business — anmatter of spirit, of passion, and of emotion.nWhen our spirit is aroused it grips the fabric of time veryndifferently than when it is relaxed. When we are positivelynengaged with the external world, we stride through hme. Ifnwe are in love and in the company of our loved one, on annadventure with friends, or within sight of a long-sought-afternobjective, time seems to zip by so that we don’t even noticenit. But when we are negatively engaged with the world—ifncircumstances become threatening — our spirit dawdles,nand time drags. Most people know how five minutes in thendentist’s chair can seem like five hours of mundane existencenelsewhere. And the presence of the threat of violentndeath almost freezes time. In Life and Fate, VasilynnnGrossman, who was a World War II war correspondent,ndescribes the hellish fighting at Stalingrad: “The distortionnof the sense of time during combat is something still morencomplex. . . . And as for hand-to-hand fighting — that takesnplace quite outside time.”nThese examples of time’s elasticity in life as we experiencenit, as the bittersweet adventure it is, square with a flownof time that springs from the mind, not the external world.nThe view is far from new. It bubbles under the surface ofnordinary language, often bursting into the open in everydaynsayings, such as: “Life is a journey, not a destination.”nWhat is new is that the description of life as an activenjourney now rests on the sure quantitative foundation ofnexact empirical science. Science has no idea what consciousnessnis, but, whatever it is, movement through time must benits key aspect. We can no more stop our headlong rush intonthe future and continue to live than an airplane can stop itsnmotion through the air and stay in the sky.nThe implications of this, however, have not sunk in to thenscientific or the medical or the general awareness. Sleep, forninstance, is a subject where, very likely, the realization thatnlife is an odyssey of the spirit will aid understanding.nArticles about sleep in learned journals or encyclopediasnsuggest that it is a mysterious business — its purpose unknown.nFor example. Dr. Allan Rechtschaff^en of thenUniversity of Chicago, who has pursued sleep’s secret withnstudies of crocodiles, rats, and humans, says: “Perhaps sleepndoes not have a function. . . . Perhaps we should accept ournfailure to isolate a specific function for sleep as evidence fornnonexistence of a function. But it is hard to believe that wenspend almost one-third of our lives in a behavioral state thatnhas no function at all.”nConventionally, we think that we sleep because we arentired. When we say this we mean the physical fatigue thatnfollows an active day, and we look on sleep as a naturalnrespite. H.G. Wells expresses this view in “The War of thenWorlds” when he describes the differences between Martiansnand humans: “Their physiology differed strangely fromnours, their organisms did not sleep, any more than the heartnof man sleeps. Since they have no extensive muscularnmechanism to recuperate, that periodical extinction wasnunknown to them.”nBut if we keep the flight of the spirit that we know as lifenin mind, then the speculation that sleep’s first purpose mustnbe to rest the spirit, not the body, suggests itself. After all, it isnthe spirit, not the body, that moves through time; the body isnthe home in which the spirit dwells. One second of time isnequivalent to 186,000 miles, so the 16 waking hours of antypical day are equivalent to 24,000 billion miles, or IInround trips to Jupiter. Would you be puffed-out afternmaking 11 nonstop round trips to Jupiter without anynartificial aid whatsoever? You bet. Martians probably neednsleep too.nThe ravages of an epidemic that swept Europe andnAmerica in the 1920’s reveal the close links between sleep,nthe flow of time, and life. This dreadful disease, a sleepingndisorder known as encephalitis lethargica or sleeping sickness,nfirst appeared in Europe in 1917, spread to America,nand then faded away, so that by 1927 it had disappeared. Innits wake the disease left five million victims of whom onenthird died. Those who succumbed died in a deep coma or inn