Piero Scaruffi

Dreams (These are excerpts from, or extensions to, the material published in my book "The Nature of Consciousness") The Interpretation of Dreams The bizarre, irrational nature of dreams, where reality gets warped and laws of nature are turned upside down, and why we remember them at all have puzzled humans since ancient times. Ancient people believed that dreams were the vehicle that the gods used to communicate with mortals. Dreams belonged to the sphere of the supernatural. Dreams were due to external forces. In almost all civilizations people believed that dreams had to be interpreted, i.e. that they had a meaning and that specialists (whether oracles or priests) could figure out that meaning. Aristotle tried in vain to demystify dreams, arguing that their story-line was accidental and meaningless, that they reflected the events of the day, and that they were ultimately caused by imbalances in the body. Dreaming is a process that absorbs a lot of energy; therefore, it must serve a biological purpose, possibly an important one. In 1900 the Austrian neurologist Sigmund Freud advanced a theory of dreams that stood on the following principles: 1. Dreams are composed of sensory images; and 2. Free associations are evoked in the dreamer's mind by these images. He concluded that dreams rely on memories and that they are assembled by the brain to deliver a meaning. Meaning of dreams are hidden and reflect memories of emotionally meaningful experiences. The classical world of Psychology was a world in which actions have a motive. Motives are mental states, hosted in our minds and controlled by our minds. Motives express an imbalance in the mind, between desire and reality: action is an attempt to regenerate balance by changing the reality to match our desire. Freud's conceptual revolution consisted in separating this mechanism of goal-directed action from the awareness of it. Freud suggested that motives are sometimes unconscious, i.e. that we may not be aware of the motives that drive our actions. There is a repertory of motives that our mind, independent of our will, has created over the years, and they participate daily in determining our actions. Our conscious motives, the motives that we can count, represent only a part of our system of desires. Freud interpreted dreams accordingly. A dream is only apparently meaningless: it is meaningless if interpreted from the conscious motives. However, the dream is a perfectly logical construction if one also considers the unconscious motives. It appears irrational only because we cannot access those unconscious motives. Freud' fundamental thesis was hidden (ironically, it was itself unconscious): that all mental life is driven by motives/desires. Freud never justified it and spent the rest of his life analyzing the content of dreams for the purpose of eliciting the unconscious motives (i.e., of "interpreting" the dream), focusing on sexual desires (a prime example of censored motives in his time) and childhood traumas (which somehow he believed were more prone to generate repressed motives). Freud never even tried to explain the mechanism by which repression of motives operates (by which the unconscious is created, by which some motives are selected over others as undesirable and then such motives are repressed but kept alive and active) and the mechanism by which unconscious motives re-emerge during sleep (by which sleep transforms those repressed motives into a flow of scenes). Freud's work had an unfortunate consequence: psychiatrists became more interested in the "content" of dreams than in the "form" of dreaming. Psychiatrists kept looking for the "meaning" of dreams, rather than for the "source" of dreams. Psychiatrists studying dreams behaved like doctors analyzing symptoms of a disease or of an injury. However, unlike doctors, who knew the anatomy of the body, psychiatrists knew nothing of the neural processes of the brain. This historical accident basically caused dreams to remain outside the sphere of science for seven decades. (Freud's impact, incidentally, has always been larger in the arts than in the sciences). The Interpretation of Dreaming Much more important was a finding that remained neglected for almost a century: at the end of the 19th century the British neurologist John Hughlings Jackson realized that a loss of a brain function almost always results in the gain in another brain function. Typically what is gained is heightened sensations and emotions. Jackson, virtually a contemporary of Darwin, explained this phenomenon with the view that the brain's functions have different evolutionary ages: newer ones took over older ones, but the older ones are still there, we just don't normally need to use them as the newer ones are more powerful. When we lose one of the newer features, then the older features of the brain regain their importance. Jackson had the powerful intuition that a single process was responsible for a "balance" of brain states. An important discovery (probably the one that opened the doors of the neurobiology of dreams) occurred in 1953 thanks to the USA neurologist Nathaniel Kleitman: dreaming is associated with a brain state of "rapid eye movement" (REM) that recurs regularly during sleep. A brain enters REM sleep 4 or 5 times per night, at approximately 90-minute intervals, and each period lasts about 20 minutes. In 1962 the French physiologist Michel Jouvet observed that REM sleep is generated in the pontine brain stem (or "pons"). In other words, Jouvet localized the trigger zone for REM sleep (and therefore dreaming) in the brain stem. REM sleep exhibits four main properties: A low level of brain activity The inhibition of muscle tone Waves of excitation from the pons Rapid eye movement The waves of excitation are probably the cause of everything else. The pons sends signals and excites eye muscles (causing rapid eye movement), the midbrain (causing a low level of brain activity), and the thalamus. The thalamus contains structures for visual cognition, auditory cognition, tactile cognition and so forth. The thalamus then excites the cortex. The cortex therefore receives a valid sensory signal from the thalamus and interprets it as if it were coming from the eye, ears, etc. During REM sleep several areas of the brain are working frantically, and some of them are performing exactly the same job they perform when the brain is awake. The only major difference is that the stimuli they process are now coming from an internal source rather than from the environment: during dreams the sensory input comes from the sensory cortex. In 1977 the USA neurophysiologist Allan Hobson proved that, far from being the center of production of dreams as Freud imagined, higher brain functions such as memory and emotion are simply responding to a barrage of stimuli that are generated from the brainstem. Dreams Are Made Of This There are three main categories of explanation for dreams. The simplest explanation is that dreams are just an evolutionary accident. By accident we have five fingers rather than four. By accident we dream while we sleep. Another explanation is that they are fossils of a previous form of mind, accidental remnants of previous brain processes. Yet another explanation is that they are a window on some kind of processing that goes on in the brain while we sleep. Imagine that somebody is filing a lot of newspaper clippings into folders and that you are standing in front of him: you will see a rapid sequence of titles flashing in front of your eyes. While you understand each of them, the flow of titles is cryptic: it may form, by mere chance, stories, but stories that you cannot understand. In reality the sequence of titles is not random, because the person who is filing the titles is following a method (for example, they are filed in chronological order, or in order of importance, or by subject matter). It is just that you are only a spectator of the process, trying to make sense of the output of that process. This could be exactly what is happening to our consciousness while we are sleeping. The brain is rapidly processing a huge amount of information in whatever order and our consciousness sees flashes of the bits that are being processed. These bits seem to compose stories of their own, and no wonder that the stories look weird if not undecipherable. This third hypothesis is consistent with the behavior of the brain. The brain, far from being asleep, is very active during sleep. Most nerve cells in the brain fire all the time, whether we are awake or asleep. The process that takes place during dreams is most likely about remembering and forgetting, i.e. REM sleep is important for consolidating long-term memories. An important clue if that the brain is not only very active during sleep, but sleep states and awake states are quite similar. The Genetic Meaning Of Dreams Jouvet was also a pioneer of the theory that dreams have a function. To derive crucial action patterns from the genetic program of the individual. REM sleep provides a means to combine genetic instructions with experience. Sleep and dreaming are a survival strategy. Jouvet thinks that a dream is the vehicle employed by an organism to cancel or archive the day's experiences on the basis of a genetic program. This explanation would also reconcile the dualism between hereditary and acquired features: how much of what we know is innate and how much is acquired by experience? In Jouvet’s scenario, an hereditary component is activated daily to decide how new data must be acquired. In particular, Jouvet showed that psychological differences across individuals are maintained by a sort of continuous reprogramming that takes place during REM sleep. This process wipes out "certain aspects of what we have learned", while reinforcing the "unconscious reactions that are the basis of personality". More than Freud's pathological theory of dreaming, this resembles the theory of the Swiss psychologist Carl Jung, that dreams reflect the "collective unconscious", a shared repertory of archaic experience represented by "archetypes" which spontaneously emerge in all minds. One only has to adapt Jung's thought to genetics in order to obtain Jouvet’s theory. The universal archetypes envisioned by Jung could represent a predisposition by all human brains to create some myths rather than others, just like, according to Chomsky, all human brains inherit a predisposition towards acquiring language. The Adaptive Value Of Dreams The USA neurobiologist Jonathan Winson expressed this concept in a more general way: dreams represent "practice sessions" in which animals (not only humans) refine their survival skills. REM sleep helps the brain to "remember" important facts without having to add cortical tissues. During REM sleep the brain (specifically, the hippocampus) processes information that accumulated during the day. In particular, during REM sleep the brain relates recent memories to old memories, and derives "tips" for future behavior. Dreams are a window on this "off-line processing" of information. The neocortex processes sensory input and sends it to the hippocampus, which acts as a gateway to the limbic system. The limbic system mediates between sensory input and motor output. At birth, the hippocampus is needed to retrieve information stored in long-term memory, but, after about three years, the brain somehow learns how to access directly such information. Dreams may explain how this happens. During REM sleep, the time when we dream, the neocortex is working normally, except that movement in the body is inhibited. Most mammals, except for primates, exhibit a theta rhythm in the hippocampus (about six times per second) on only two occasions: whenever they perform survival-critical behavior, and during REM sleep. Winson deduced that REM sleep must be involved in survival-critical behavior. Early mammals had to perform all their "reasoning" on the spot ("on-line"). In particular they had to integrate new information (sensory data) with old information (memories) immediately to work out their strategies. Winson speculates that at some point in evolution brains invented a way to "postpone" processing sensory information by taking advantage of the hippocampus: REM sleep. Theta rhythm is the pace at which that ("off-line") processing is carried out. Instead of taking input from the sensory system, the brain takes input from memory. Instead of directing behavior, the brain inhibits movement. But the kind of processing during REM sleep is the same as during the awake state. Winson speculates that this off-line processing is merging new information with old memories to produce strategies for future behavior. Theta rhythm disappeared in primates, but REM sleep remained as a fundamental process of brains. In humans, therefore, REM sleep, i.e. dreams, corresponds to an off-line process of integration of old information with new information. Dreaming is an accidental feature that lets us "see" some of the processing, although only some: a dream is not a story but a more or less blind processing of the day's experience. Winson goes as far as to suggest that all long-term memory may be constructed through this off-line process (i.e., during REM sleep). During sleep, the hippocampus would process the day's events and store important information in long-term memory. There is a biologically relevant reason to dream: a dream is an ordered processing of memory that interprets experience that is precious for survival. Dreaming is essential to learning. Winson relates this off-line process that operates during sleep with Freud's subconscious. Freud was right that dreams are the bridge between the conscious and the unconscious, although that bridge is of a different nature. The Freudian "subconscious" becomes the phylogenetically-ancient mechanism involving REM sleep, in which memories and strategies are formed in the cortex. We Dream to Remember and to Forget Similarly, Hobson thinks that the ultimate purpose of dreams is to populate long-term memory, to help us learn. We dream hypothetical situations so that we will be prepared to face real situations of the same kind. When a situation occurs during the day, it has probably already been played at least once at night in our dreams, and we know what to expect. By dreaming, we train our brain: dreams are mental gymnastics. It's like saying that, in order to see something, we must first create the vision of that something in our mind. In a sense, we dream what is worth remembering. By contrast, in 1983 Francis Crick proposed that the function of dreams is to "clear the circuits" of the brain, otherwise there would not be enough space to register each day's events. The brain, in the face of huge daily sensory stimulation, must: understand what matters understand what does not matter remember what will still matter forget what will never matter again Dreams help eliminate useless memories. Therefore, according to Crick, we dream what is worth forgetting. What is still missing is the physical link between dreams and genome. Neurotransmitters (such as animenes and cholines) act on the surface (the membrane) of the cell, whereas genes lie in the center (the nucleus) of the cell. Messenger molecules transfer information from the membrane to the nucleus and viceversa. Allan Hobson has hypothesized that neurotransmitters may interact with messenger molecules and therefore affect the work of genes. If during sleep the brain is consolidating memories that have been acquired during the day, then dreaming, far from being an eccentric manifestation of irrationality, is at the core of human cognition. Dreams as a Chemical System Hobson thinks that, whether asleep or awake, the brain always does pretty much the same thing. The dreaming brain employs the same systems and processes of the awake brain, except that those processes are not activated by stimuli from the outside world; that the outcome of those processes does not result in (significant) body movements; and that self-awareness and memory are dormant. The input, the output, the processor and the working space of the awake brain are replaced by something else; but the "software" is the same. What makes a difference is the neurotransmitters that travel through the brain. What differs between awake and asleep states is very small, but enough to alter dramatically the outcome: during sleep the brain is bombarded by erratic pulses from the brain stem and flooded with nervous system chemicals of a different sort. Neurotransmitters make brain circuits more or less sensitive. Aminergic neurotransmitters originate in the brain stem and terminate in the amygdala. Cholinergic neurotransmitters originate in the forebrain and terminate in the cortex. During waking states, the brain is controlled by the aminergic neurotransmitters, made of molecules called "amines". During sleep, the brain is controlled by the cholinergic neurotransmitters, made of a molecule called "acetylcholine". Cholinergic chemicals free the system used for cognition and behavior. They paralyze the body by sending pulses to the spinal chord, even though motor neurons are always in motion. Hobson’s idea is that wake and sleep are two different chemical systems hosted in the same "processor". These two chemical systems are in dynamic equilibrium: if one retracts, the other advances. This means that our consciousness can fluctuate between two extremes, in which either of the chemical systems totally prevails (neither is ever completely absent). This also means that the brain states of wake and sleep are only two extremes, between which there exists a continuum of aminergic-cholinergic interactions, and therefore a continuum of brain states. This system can be said to control the brain. It resides in the brain stem and from there it can easily control both the lower brain (senses and movement) and the upper brain (feelings and thought). When it doesn't work properly, when the balance of chemicals is altered, mental diseases like delirium occur. It is not surprising that diseases such as delirium are so similar to dreams: they are driven by exactly the same phenomenon. Hobson claims that the brain is in awake, dream or (non-REM) sleep mode depending on whether amines are prevailing, cholines are prevailing or amines and cholines are "deadlocked". Three factors account for the brain behavior at any time: activation energy (amount of electrical activity), information source (internal or external) and chemical system (amines or cholines). When activation energy is high, the information source is external and the mode is aminergic: the brain is awake. As activation energy decreases, the external information source fades away and amines and cholines balance each other: the brain falls asleep. When activation energy is high, the information source is internal and the mode is cholinergic: the brain is dreaming. During an hallucination: activation energy is high, the information source is internal and the mode is aminergic. In a coma: activation energy is low, the information source is internal and the mode is cholinergic. The extremes are rare and usually traumatic. Normally, both external and internal sources contribute to cognitive life, and both amines and cholines contribute to the brain state. The interplay of external and internal sources means that our perceptions are always mediated by our memory. Hobson thinks that our brains do not merely react to stimuli: they also "anticipate". The internal source tells us what to expect next, and thus helps us cope with the external source. Emotions are, in a sense, a measure of how well the internal source matches the external source: anxiety is caused by a major mismatch, whereas contentedness is a sign of matching sources. When we dream, the spinal cord is paralyzed and the senses are disconnected. This is because of the cholinergic neurotransmitters that come from the brain stem. Hobson believes that sleep has the function to reinforce and reorganize memory: ultimately, to advance them from short-term memory to long-term memory. Amines are necessary for recording an experience, while cholines consolidate memory. Again, it looks like during REM sleep memory is consolidated. The aminergic system is responsible for attention, focus, awareness. The cholinergic system is responsible for the opposite process: focus on nothing, but scan everything. As for the content of dreams, Hobson thinks that they reflect a biological need to keep track of place, person (friend, foe or mate) and time. He draws this conclusion from considerations about what is typical (and bizarre) of dreams: disruptions in orientation. The bottom line is that dreams are meaningful: the mind makes a synthetic effort to provide meaning to the signals that are generated internally (during a dream, memory is even "hypermnesic", i.e. is intensified). Wishes are not the cause of the dreaming process, although, once dreaming has been started by the brain stem, wishes may be incorporated in the dream. Therefore, Hobson thinks that dreams need not be interpreted: their meaning is transparent. Or, equivalently, dreams must be interpreted in the realm of neurophysiology, not psychology. The interplay between the aminergic and the cholinergic systems may be responsible for all conscious phenomena (for Hobson, dreams are as conscious as thinking) and ultimately for consciousness itself. After all, conscious states fluctuate continuously between waking and dreaming. Dreams, far from being subjective, are "impersonal necessities forced on brain by nature". The Origin of Dreaming In the 1960s the USA psychiatrist Fred advanced the hypothesis that, from an evolutionary perspective, REM sleep came first and dreams came later. First bodies developed the brain state of REM sleep, which was retained because it had a useful function for survival (for example, because it kept the brain alert and ready to react to emergencies even during sleep), and then dreams were engrafted upon REM sleep. REM sleep was available and was used to host dreams. Dreaming evolved after a physical feature made them possible, just like language evolved after an anatomical apparatus that was born for whatever other reason. Dreaming, just like language, is an "epiphenomenon". The psychologist Anthony Stevens has provided a practical explanation for why some animals started dreaming: dreaming emerged when oviparous animals evolved into viviparous animals. By dreaming, the brain could augment its performance with some "off-line" processing. This made it possible to limit the size of the brain while leaving brain activity free to grow. Brains, and thus heads, would remain small enough to pass through the maternal pelvis. In Winson's scenario, dreams helped us survive a long time before our mind was capable of providing any help at all. And dreams, unlike higher consciousness, are likely to be common to many species. The mind could well be an evolution of dreaming, which happened in humans and not in other species. First the brain started dreaming, and then dreams took over the brain and became the mind, which could be viewed as a continuous dream of the universe that we inhabit. This hypothetical history of the mind does not differ too much from the one in which the mind was created by memes. The relationship between memes and dreams is intuitive, and the psychologist Joseph Campbell indirectly summarized it with his celebrated aphorism that "a myth is a public dream, a dream is a private myth". An Evolutionary Accident In contrast to Jouvet, Hobson and Winson, the USA philosopher Owen Flanagan thinks that both sleep and consciousness are products of evolution, but consciousness during sleep (dreaming) is merely an accident of nature, a side effect of the two. Both consciousness and sleep have a clear biological function, but dreams don't. During sleep the brain stocks up neurotransmitters that will be used the next day. By accident, pulses that originate from this stockpiling chore (coming from the brain stem) also reactivate more or less random parts of memory. Unaware that the body is actually sleeping, the sensory circuits of the cerebral cortex process these signals as if they were coming from outside and produce a chaotic flow of sensations. Thus we dream. Dreams are just the noise the brain makes while working overnight. If Flanagan is correct, dreams are meaningless and pointless. Of course, indirectly, dreams tell us something about how our mind works, because, after all, whatever we perceive while we dream is the product of what is in our memory and of how our cerebral cortex processes those memories. But the usefulness of the dream-narrative is really limited to an almost "diagnostic" purpose. As our cerebral cortex tries to make sense of that chaotic input, we can learn something about its cognitive functioning, just like by running the engine of a car when it is not moving we can learn something about a noise it makes on the freeway (but the engine running while the car is not moving has no hidden meaning). Of How Real Dreams Are and How Dreamy Reality Is The experience of a dream may feel so utterly bizarre for today's mind, but we have to go back millions of years to realize that it is probably far less bizarre than it appears to us today. It is likely that, millions of years ago, our waking life was not too different from our dreaming life. Consciousness in dreams is a series of flashes that are fragmented and very emotional. It is likely that awake consciousness had exactly the same character: mostly nothing would happen to our consciousness (no thinking, no emotions, just mechanic, instinctive behavior) but situations would present suddenly that would arouse strong feelings and require immediate action. Our awake life "was" a series of emotionally charged flashes, just like dreams. The difference between being awake and dreaming was only the body movement. As we rehearsed the day's events during dreams, we would feel that the sensations are perfectly normal. Today our consciousness has acquired a different profile: it has evolved to a more or less smooth flow of thoughts, in which strong emotions don't normally figure prominently. We think when we are commuting on a bus or while we are shopping in the mall, and the most violent emotion is being upset about the price of a shirt or suddenly realizing we just missed our stop. They are peanuts compared with the emotion of being attacked by a tiger or of being drawn by strong currents towards the waterfall. Our awake consciousness has changed and dreams have remained the same. The brain is still processing off-line, during sleep, our day's events with the same cerebral circuits that we had millions of years ago, and therefore it is still generating the same flow of emotionally-charged flashes of reality. When the brain is awake, reality does not impinge on those circuits in the same way it did in the hostile, primitive environment of million of years ago. The world we live in is, by and large, friendly (free of mortal foes and natural catastrophes). But when danger does appear (a mortal foe or a natural catastrophe), then our awake life becomes just like a dream: "it was a nightmare", "it didn't feel real", etc. In those rare and unfortunate circumstances (that hopefully most of us will never experience) our waking life feels just like a dream: flashes of reality, violent emotions, apparent incoherence of events, etc. Because of the society that we have built and the way we have tamed and harnessed nature's unpredictability through civilization, our brain does not receive the sudden and violent stimuli it used to. This is what makes most of the difference between being awake and dreaming. It is not just a different functioning of the brain: it is a different functioning of the world around us. NREM Sleep In 1997 the South African psychiatrist Mark Solms argued that the identification of dreaming and REM is incorrect, because, he believes, dreaming is possible without REM (Non-REM dreaming or NREM dreaming). He also claims to have located the origins of dreaming in the ventral tegmental area of the midbrain, and not in the pons (as Jouvet and Hobson believe). Therefore Solms believes that the dopaminergic system (the one originating in the ventral tegmental area) is the neurochemical basis for dreaming. Hobson believes that dreaming has its origins in the same region of the pons that generates REM sleep. Solms believes that only REM originates in the pons, i.e. that dreams and REM are physically controlled by two different regions of the brain. The Collective Memory of Myths Influenced by Carl Jung, in the 1940s the USA anthropologist Joseph Campbell argued that a few themes are ubiquitous in myths around the world. Myths recur in different civilizations and evolve from one civilization to the next one. There is a continuum of myth. At the origin of a myth there is an archetype, which works as a "memory deposit". Mythology seems to be a system of entities conceived to mirror the human condition. The rites are "physical formulas" in human flesh, unlike mathematical formulas that are written in symbols, but they are also formulas that describe natural laws of the universe. Myth appears to be a system to organize knowledge about the environment and pass it on to others, in particular to future generations. The reason this system works is that it somehow takes advantage of the way the human brain works. A myth is so constructed that, once inserted in a human brain, it will provoke the desired reaction. It does not require thinking. In a sense, it "tells" you what to do, without having to prove that it is the right thing to do. It shows you the consequences, or the rewards, so you are prepared for them; or it shows you the dangers and so it saves you from experimenting them in real life. For example, when the Sumerian city yields the myth of the city of god what matters is not the historical record but the subliminal message: build such a city! The creator of the myth must craft the myth in such a way that it will trick the brain into wanting to achieve a goal. The "creator", naturally, is not one specific author, but rather the chain of humans who use and adapt the myth to their conditions. The myth evolves over many generations and eventually gets "designed" to perform his task in a very efficient way, just like any organ of the body. Campbell calls myth "the spiritual resources of prehistoric man" and insists on the "spiritual unity" of the human race: the spiritual history of the human race has unfolded roughly in the same way everywhere. Campbell also implies that myth, just like language and just like genes, obeys a grammar. Just like language and just like genes, myths have evolved from more primitive myths. Just like language and just like genes, myths are universal, shared by all humans. Just like language and just like genes, myth tells the story of mankind, as it follows the spread of races in the continents and their adaptation to new natural pressures. Campbell's viewpoint contrasts with that of the British anthropologist James Frazer, who at the end of the 19th century claimed that the similarity of myth is due to similar causes operating on similar brains in different places and times. But there may be a bit of truth in both views. A Neuroscience of Myths Noam Chomsky argued that brains are "pre-wired" for learning language. Circumstances will determine which particular language you will learn, but the reason you will learn a language is that your brain contains a "universal grammar" that is genetically prescribed. The structure of the human brain forces the brain to learn to speak. Dreams seem to be the antichamber to learning, whereby the brain processes experience and decides what has to be stored for future use. Again, this depends on the genetic programming of the brain. What is learned depends on the structure of the brain, which in turn depends on the genetic program that created the brain, which in turn was determined over millions of years by evolution. Basically, it looks like brains learn what they have been programmed to learn by evolution. Human brains have been programmed by evolution to learn some things rather than others. If this is true, then myths could have a simple explanation: they are the simple ideas that the structure of our brain can accommodate. The universal archetypes envisioned by Jung and Campbell could well be predispositions by all human brains to create some myths rather than others, just like, according to Chomsky, all human brains inherit a predisposition towards acquiring language. If myths arise in the mind because the brain has been programmed to create them, then, to some extent, we think what we have been programmed to think. Down this path of genetic determination of our beliefs, one could wonder if genetic differences between the races can account for slightly different behavior. Do Italians speak Italian and French speak French because their brains developed in slightly different ways over thousands of years of independent evolution? Did Arabs develop Islam and Europeans Christianity because their brains are slightly different, and the myths they can create are slight variations of the myth of god? How plastic is our mind, and how strong is the hand of fate? A History of Concepts One could argue that ancient gods simply represent concepts. As concepts were forming in human minds, human minds expressed them as concepts. And their interaction yielded religions. Ancient gods represented qualities, mountains, rivers, forces of nature, emotions. Gods were vehicles for natural forces to express themselves. Gods were created for each new phenomenon or discovery. Ancient religions were systems of concepts: they classified and organized concepts through a network of legends (symbolic narratives) and a series of rites (symbolic actions) in a manner not too different from how Marvin Minsky’s "frame" organizes knowledge. A legend expressed the function of the force in nature and in relation to other forces. A rite expressed the attributes of the force. They were "local": each culture developed different sets based on local circumstances. As lower concepts gave rise to higher, more complex concepts, old gods were replaced by new gods (e.g., the god of thunder or of the Nile was replaced by the god of fertility or of harvest). New gods were created as the mind progressed from purely narrative/literal concepts to more and more abstract concepts. At some point there arose the concept of all concepts, the concept of Nature itself, the concept of the supreme power and of everything that exists, of the force that is behind all other forces. Thus monotheistic religion was born. God became not the vehicle for a force but "the" force itself. Religion is, ultimately, a way to pass culture (a system of concepts) on to future generations. People of different religions have not only different rites (physical lives) but also different mental lives, because they think according to different conceptual systems. There is no one-to-one correspondence between Roman gods and Indian gods, and that explains why ancient Rome and ancient India were completely different societies: they had completely different concepts, i.e. people thought in completely different manners. In that sense, monotheistic religion represents a major leap forward in cognitive skills. Just like the zero enabled higher mathematics and the roman arch enabled taller buildings, so the single-god religion enabled higher thinking. Child's Play Why do children play? Isn't that also a way of rehearsing real-life situations based on the genetic repertory? Doesn't play also have the irrational quality of dreams? Isn't playing a way to accelerate the same kind of learning that occurs during dreaming? Could it be that at the beginning of our life everything is but a dream, and then slowly reality takes over (thanks to social interaction) and dreams are relegated to sleep? Joking What have joking and dreaming in common? Apparently nothing, but both belong to the category of acts that do not seem to have a useful function. Like dreaming, joking seems to be a pointless waste of energies. Like dreaming, joking is some kind of playing with our experience. Like dreaming, joking is a process of rearranging our experience in a somewhat irrational way. Like dreams, jokes do not necessarily require linguistic skills, but normally occur in a linguistic context. More than dreams, jokes seem to have developed in humans to a level far more sophisticated than in any other species. We see animals play and laugh, but the gap between a comedian and two lion cubs wrestling in the grass is enormous. While there may be no biological evidence to support the idea that jokes have a specific function for our learning and survival, one wonders why we enjoy so much making them. Woody Allen once said that comedy is tragedy plus time: when something tragic occurs, it is inappropriate to make fun of it, but months or years later it may be perfectly appropriate. If I trip on something and break my leg, I am in no mood to hear a joke about it, but it is more than likely that years later somebody will mock me on this subject. Jokes refer to past experience, and usually refer to tragic experience. If not tragic, then significant in some way. The point is that, indirectly, jokes help us to learn and to remember. Jokes help us rehearse survival techniques in the environment. Jokes help us prepare for reality. Jokes tell us which situations we should avoid at all costs. Jokes, like dreams, are a brain's way to train itself without risking its life. Further Reading Campbell, Joseph: THE MASKS OF GODS (Viking, 1959) Flanagan, Owen: DREAMING SOULS (Oxford Univ Press, 1999) Hobson, Allan: THE DREAMING BRAIN (Basic, 1989) Hobson, Allan: THE CHEMISTRY OF CONSCIOUS STATES (Little & Brown, 1994) Jouvet, Michel: LE SOMMEIL ET LE REVE (Jacob, 1992) Jouvet, Michel: THE PARADOX OF SLEEP: THE STORY OF DREAMING (MIT Press, 1999) Jung, Carl: THE ARCHETYPES OF THE COLLECTIVE UNCONSCIOUS (1936) Snyder, Frederick: EXPERIMENTAL STUDIES OF DREAMING (Random House, 1967) Solms, Mark: THE NEUROPSYCHOLOGY OF DREAMS (Erlbaum, 1997) Winson, Jonathan: BRAIN AND PSYCHE (Anchor Press, 1985)