Introduction.

The organizational structures of living beings can be visualized in stratified levels, but they are not separate levels, they interlink or inter-leave, so to speak. That is, higher levels reach into lower levels and lower levels feed back up to higher levels, in a manner of mutual penetration or interdependence. The whole structure is thus not decomposable into separate parts, but forms a holistic entity, a “system” that is more than the sum of its parts, because of these inter-level interactions.

Yet it is convenient analytically to discuss these levels separately, as long as we remember, at the end, to reassemble them synthetically. A symphony does not really suffer if we describe separately the role of the violins and the wind instruments, but then we should listen to the whole orchestra playing together.

To some extent, the levels may correspond to the temporal sequence of the appearance of these levels in evolution, but again in an interwoven, overlapping manner. In time sequence, we do not encounter one level being perfected or finished before the next one begins, or even the one after that. It is somewhat like the electron shells of atoms filling up as we proceed from element to element in the periodic table: the sequence 1s, 2s, 2p, 3s, 3p, 3d, 4s, 4p, 4d, 4f, 5s and so on, does not go in that order, but intertwines; in that, for example, the filling of 3d is postponed until after the first part of 4p, and 4f until after part of the 5d which comes after part of the 6p. (The d’s are the transition metals and the fs are the rare earths.) It is an intricate and beautiful pattern, like a knitted rug. (This is explained in more detail in the preceding essay, “Intertwining Levels”.)

After these general considerations, it is time to specify the levels in the functioning of living beings that we have in mind. These levels are: the metabolic, the genetic, the epigenetic, the immune, the hormonal, and the neural. (This scheme was suggested by Erich Jantsch in “The Self-organizing Universe” and is somewhat modified here.) Further levels in human societies (also “living systems” in Miller’s sense) are: the sensory or pre-linguistic, the linguistic- oral, the literate, the technological, and possibly the extrasensory (future and perhaps already foreshadowed).

These are all modes of communication, ways of structuring cooperation, bonds of love in some primordial sense, all the way from the metabolic at the origin of life and the technological of the present or the extrasensory of the future. They are, in a way, the hallmarks of an emergent mind, first cellular, then organismic-individual and then planet-wide social. This “mind” is newly emerging, and yet really an unfolding (in Bohm’s sense) of a pre-existing eternal entity – an incarnation of God – the Word becoming Flesh – the enfolded order of holistic coherence becoming manifest. God is both transcendent (i.e. preexisting as Creator) and immanent in Nature (i.e. permanently incarnated as Word or Meaning in Flesh).

Yet the communication links should not be pictured in some vague and mystical manner as “bonds of love” only; they often more resemble Rube Goldberg machines of weird submicroscopic natural technology. (These two views are not at all contradictory; they are complementary.) Nature is revealed as a superb inventor-tinkerer in a very precise and practical manner, not working by some mana-like emanations of disembodied spiritual “energy” understood in the esoteric sense.

It is time now to describe in a more detailed way what phenomena and structures are contained in each of these levels. It will be understood, of course, that these are only sketches. Whole books have been written, whole scientific disciplines have been constructed, of each of these levels. Yet the links between them have sometimes been neglected in the rush of overspecialization.

The Metabolic Level.

At this level, which presumably was the first to appear on Earth (I agree with Freeman Dyson in “Infinite in All Directions” that proteins came before the nucleic acids) (see “The Origin of Life” in Section VIII), we observe the processes of energy production, energy use and storage, and the flowthrough of substances (“Stoffen-wechsel” in German means “exchange of substances and is their word for metabolism, whose Greek derivation is “metanoia” or change.) The flow-through of materials is an essential characteristic of life, since life can only exist as an open system far from equilibrium, as Prigogine has shown. In this sense of flow-through (of form being more important than matter) (see “Matter and Form” in Section III), life is like a flame or like a river, both used as symbols of life. This property of flow-through seems to be more fundamental than reproduction – hence the plausibility of the hypothesis that proteins came before nucleic acids, enzyme-assisted substance-changes before replication.

Energy production is necessary for maintaining the balancing act lify has to perform to stay at the local apex of a free-energy or negentropy “hill”. Energy production is achieved either by fermentation (the primitive mode performed by some of the prokaryotic bacteria – the so-called anaerobic ones) or by the photosynthesis-plus-respiration process, the more “modern high-tech” way invented already by a subsection of the bacteria (photosynthesis by the cyano-bacteria and respiration by the aerobic bacteria). (See also the essay “Evolution of Mind” in Section VI.)

There has since developed a division of labour or specialization, by which photosynthesis is carried out almost exclusively by plants, while animals carry on more of the rapid locomotion which requires more extensive respiration. Plants respire too, but in them the rates of photosynthesis exceed the rates of respiration, at least in bright sunlight. Thus they can supply the excess accumulated energy to the animals through the food chain, albeit “involuntarily”, by being eaten.

Animals (and fungi too) are thus always parasites on plants. Plants are autotrophic, i.e. selfreliant and self-sufficient, while animals are dependent – but can also be regarded as exploiters. The situation of interdependence here is somewhat like that in the globalized interdependence of world trade: the North or the animals get the better part of the deal, while the South or the plants are, of course, literally the grass roots, the basis of the world economy or the food chain.

Who is “higher” or “lower” here depends on a judgment whether self-reliance is more valued than dominance. The predator seems “higher”, the parasite “lower”, but it comes to the same thing: dependence by robbing the primary self-reliant producers and suppliers. Animals could not exist without plants, and yet mercilessly exploit them. Other parallels from human society come to mind instantly: capitalists and workers, industry and agriculture, men and women. Are such hierarchical structures .natural”? It would seem so, though it appears abhorrent.

The first prokaryotic inventors of this up-grading of the planet’s energy system, the cyanobacteria (popularly known as blue-green algae) and the aerobic bacteria, actually still operate in running Gaia’s carbon and oxygen cycle. When eukaryotic cells were formed, the cyano-bacteria became the chloroplasts of the plant cells where they carry on photosynthesis, and the aerobic bacteria became the mitochondria of all eukaryotic cells where they carry out respiration. The theory that eukaryotic cells were fOrmed by the symbiotic fusion of different prokaryotic cells was formulated by Lynn Margulis, (1981) and seems very plausible because the chloroplasts and the mitochondria still carry their own genes, quite separate from the main complement of genes in the eukaryotic cell nucleus.

Photosynthesis has also accumulated energy in fossil fuels, such as coal, oil and natural gas, exploited extensively and intensively by human users. This super-dependency on ancient plants may prove yery destructive in dumping huge quantities of carbon dioxide into the atmosphere all at once (when it was accumulated over millions of years) and thus disrupting the temperature regulation by the greenhouse effect (which is beneficial, even essential when properly balanced) and causing global warming.

After metabolic energy has been produced by photosynthesis, or, in case of the animals, from food consumed, digested and absorbed, it is either used immediately or stored. Storage can be temporary or long-range. Temporary storage and transfer to use is mediated by molecules which carry a high-energy phosphate bond; usually this is either ATP (adenosine triphosphate) or GTP (guanosine triphosphate), which, on delivering their energy to other systems which need it, become ADP or GDP respectively, i.e. the corresponding diphosphates. (Sometimes they can go all the way to the monophosphates, AMP and GMP respectively.) The high-energy phosphate group usually phosphorylates a protein which is thereby activated to do work and perform the function for which it was designed, or it transfers the energy to yet another protein which does so. (Cascades are very common.)

A TP and GTP are really phosphorylated nucleotides, or monomers of nucleic acids. Freeman Dyson’s theory is that, early in the evolution of life, they accidentally polymerized to the nucleic acids RNA and DNA (probably RNA first), which turned out to have the capability to replicate themselves. At first this accidental event was a disaster like a sickness, but it eventually turned out to be very useful, and is now quite essential. (See again “Origin of Life”, Section VIII.)

The symbiosis of proteins and nucleic acids led to the prokaryotic cells, i.e. bacteria. This symbiosis thus preceded by many aeons the later symbiosis, already mentioned above, of several prokaryotic cells to produce the larger eukaryotic cell, of which all protozoa, fungi, plants and animals are composed. Once eukaryotes existed, multicellular organisms became possible (another symbiosis step), and so we witnessed the “Cambrian explosion” of animal diversification, from which stem our first observed fossils.

If the putative life forms composed only of protein are called akaryotic cells (my term), then we have the three steps of increasing symbiotic integration: 1. from akaryotes to prokaryotes (proteins and nucleic acids start to cooperate), 2. from prokaryotes to eukaryotes (several prokaryotes merge), and 3. a multitude of eukaryotic cells get together to form multicellular organisms. Will there be a 4th step, integration of multicellular creatures to multi-individual societies? Highly integrated ant and bee societies already exist which would qualify as such; human societies are still not integrated enough to act as units. Perhaps we would not want them to, for fear of fascist totalitarianism. (1 guess 1 am showing my Western individualistic bias.)

The step from nucleotides to nucleic acids leads straight from the metabolic level to the genetic level (we warned the reader that the levels were intertwined!), and we shall not pursue this any further now, because we are not through yet with describing the metabolic level.

Long-term energy storage occurs partly in glycogen and starch (polymers of glucose as the primary product of photosynthesis and a component of many foods). Starch is stored mainly in plants and glycogen (“animal starch”) in animal liver and muscles. Glycogen stores are drawn on during mild exercise or for normal use. Even more long-term storage occurs in fats, which are readily interconvertible metabolically with carbohydrates, but less readily than glycogen or starch; this storage is drawn on only during prolonged or strenuous exercise (when runners get their “second wind”) or during starvation.

Metabolic transformations are mediated by enzymes, organic catalysts which are almost always proteins. Their high specificity for a single substrate (or a narrow class of substrates) depends on the folding or conformation of the protein to provide a favorable site or pocket for the reagents to come together, or for the single reagent to re-arrange its structure. What matters is not only the size and the shape of the pocket, but also the nature of its internal surface – acid or basic groups, hydrophilic or lipophilic ones, positive or negative charges. These properties come from the side chains of the amino acids which constitute the protein enzyme; among the 21 amino acids, all these varieties occur; and this is why the amino acid sequence of the proteins (specified by the genes, as we shall see) is crucial.

Energy utilization or consumption is done by either fermentation or respiration, as already mentioned. Primitive fermentations can have many substrates, depending on the bacteria – for example methane or hydrogen sulfide. These substances would have been present on the Earth in its early history, (as they are now, but in limited quantities), so that these early Archeobacteria were living on capital stocks, not on current income flows. This mode of life is not indefinitely sustainable, as the stocks get exhausted, and so something had to be done to solve this first ancient “energy crisis”.

We are now, of course, as a society living on the capital stocks of fossil fuels, which is also not sustainable. We shall also have to invent new energy sources, probably again solar, which is the source for photosynthesis. The solution to both the ancient and the modem energy crisis is the Sun; I call it “hitching our wagon to our Star”.

Archeobacteria still exist in environments where oxygen is low (since oxygen is poisonous to them): in marshes where methane is present, in deep wells, and on the ocean floor, especially around the thermal vents of the mid-ocean ridges where tectonic plates are separating and new ocean floor is welling up from the Earth’s mantle. These organisms are thought to be the earliest life forms that have existed.

The primordial energy crisis was solved by the invention of photosynthesis by another class of bacteria, the blue-green ones. This first and still the only sustainable energy-generating reaction for all of life on Earth uses sunlight to split a water molecule into hydrogen and oxygen (photolysis), and then uses the hydrogen to reduce carbon dioxide (through a complex series of reactions, catalyzed of course by enzymes) to produce the simple sugar glucose along with oxygen, which is liberated into the atmosphere.

However, it appeared that this marvellous solution to the energy crisis had a serious drawback the oxygen it liberated was a poison to the anaerobic bacteria, which then formed the majority of Earth’s living creatures. They lost their habitat on the surface and had to go hide in remote oxygen-free places, as already mentioned. But then something equally marvellous happened; the oxygen which first appeared to be a poison (the first serious pollutant from energy production) was transformed into a benefit (and eventually a necessity) by coming to be used in respiration by those organisms that learned how to do the trick.

Originally, energy was obtained from glucose by fermentation, which did not use oxygen. ThaT process, called glycolysis, splits the 6-carbon sugar glucose (through several enzyme-assisted phosphorylation steps which supply some initial energy to get it going) into two three-carbon fragments. the last of which is pyruvic acid, which can then go to lactic acid. The process could stop there, as it does when the lactic acid bacteria make milk go sour, or as happens in our muscles if we work them so hard and fast that they have no time to go on to the oxygen-consuming step which would normally follow. Or the pyruvic acid could, by another series of reactions, produce ethyl alcohol and carbon dioxide (as yeas: cells do in making bread rise or in the making of beer and wine). Or pyruvic acid could form the glycerc: and fatty acids which compose fats and become stored food.

But when oxygen became available and then plentiful through photosynthesis, a whole ne\’ process was added at the end of glycolysis: it took the pyruvic acid through the so-called Krebs cycle, no\. carried out in all mitochondria, in which through several steps the pyruvic acid is oxidized all the way t: carbon dioxide and water, liberating ten times as much energy from the same glucose molecule as glycolysis ever did. (See also essay “The Evolution of Mind” in Section VI.)

It will be noticed that this complete oxidation of glucose in aerobic respiration can be summed up (if we ignore the complex intermediate steps) as the exact opposite of photosynthesis: the latter takes carbon dioxide and water and produces glucose and oxygen, while aerobic respiration takes glucose and oxygen and produces carbon dioxide and water. The two reactions together form the basic cycle of the Gaian system run by the cyano-bacteria and aerobic bacteria, or the same in the form of cWoroplasts and mitochondria from inside the eukaryotic cells of plants and animals, keeping the total amounts of oxygen and carbon dioxide in the atmosphere constant – until someone comes along to meddle with it and upset it by burning fossil fuels.

It will also be noted that the energy absorbed from sunlight in photosynthesis is all recovered in aerobic respiration, since the two reactions are the reverse of each other and energy is conserved. In fact, the energy obtained from glucose in aerobic respiration is exactly the same as would be obtained by simply burning glucose in full access to air – just setting a match to it. Living things take it much more slowly than ordinary combustion because they could not stand the heat if all the energy were liberated at once. They had to learn to tame the reaction by taking it through very gradual steps and handing on the energy through multiple redox systems of enzymes and coenzymes. With the very powerful catalysts which enzymes are, this can be done at ordinary temperatures. (This connects to the myth explored in “Reinterpretation of Psyche’s Labours” in Section VIII.)

But if we want to know how many calories are in our diet, the scientists who tell us the calorie values of fats and carbohydrates measure them by burning the food substances in a calorimeter, because the overall energy liberated has to be the same, no matter what path was taken from the starting to the final materials.

Respiration “burns” not only carbohydrates (sugars and starches) and fats, but also proteins. The latter diffeLby containing not only carbon, hydrogen and oxygen, but also always nitrogen and sometimes sulfur. The breakdown of proteins therefore produces waste which must be eliminated or excreted. The body tries to conserve proteins, since both their production and breakdown is energy-intensive, but they do have a limited lifespan, and can also be drawn upon for energy production in case of dire need, i.e. starvation after exhaustion of stored fat.

In humans and other mammals, excretion takes place via urine, which is a filtrate from the blood produced by kidney glomeruli. Some of the solutes are transferred by passive osmosis, going down a concentration gradient spontaneously; but many have to be actively “pumped” against a concentration gradient, a process which consumes energy (is endothermic) and requires elaborate enzymatic mechanisms as well as ATP as an energy source. Under normal (e.g. non-diabetic) conditions, sugars and proteins are retained in the blood, or returned to it by active pumping if they leaked through the passive filters by osmosis.

Aquatic animals, such as fish, can excrete waste nitrogen directly as ammonia into the surrounding water, where it gets quickly diluted so that it does not accumulate and poison them. Land animals, however, have to employ other strategies, such as further processing of the ammonia to urea by mammals, or even to the more condensed uric acid, as birds do. Urea and uric acid are increasingly powerful ways of concentrating and sequestering away potentially poisonous products of protein breakdown until getting rid of them in liquid or solid form: urea dissolved in water is liquid, while uric acid is a solid. Learning how to do this was part of the adaptation of vertebrates to living on land instead of in water. When insects adapted to land living, they had to introduce similar changes.

Many more things could be said about the metabolic level, which is very rich in intricate chemistry, cycles and mechanisms. We did not enlarge on the gas exchange (oxygen for carbon dioxide) in the lungs, food elements (digestion products) being absorbed from the villi of the small intestine into the blood, digestion itself in the upper and middle gastro-intestinal tract (enzymatic breakdown of ingested proteins to its constituent amino acids, of ingested starches and sugars to glucose, of ingested fats to glycerol and fatty acids), elimination of food residues from the lower gastro-intestinal tract, elimination of harmful substances by the liver (detoxification), and many other processes.

The Genetic Level.

At the genetic level, the structure of the proteins that (as we have seen) serve as enzymes at the metabolic level, is determined by the genes, composed of DNA, whose full name is desoxyribonucleic acid. This happens via RNA (ribonucleic acid). The “central dogma” of molecular biology is that the process goes from DNA to RNA (which is called transcription) and from RNA to protein (which is called translation). However, a few viruses (including mv which causes AIDS) go backwards from RNA to DNA by the action of an enzyme called inverse transcriptase, and are called retro-viruses.

DNA and RNA have a backbone composed of sugars and phosphate groups, and side chains of purine and pyrimidine bases called adenine, cytosine, guanine, and thymine (in case of DNA), (RNA has uracil instead of thymine). These are usually abbreviated as A, C, G and T (or U). Long chains of DNA then coil around each other in a double helix. (RNA is usually a single strand.) The bases on the two DNA chains pair together through hydrogen bonds; the pairs are always AT and CG, the others do not bond. Therefore the base sequences on the two strands of the DNA double helix have to be complementary all along the very long chain, or the double helix would not form. The structure is very reminiscent of a zipper.

The base sequences along the DNA sometimes form genes, which code for proteins, but some sequences are non-coding. These are called introns and exons, respectively. Someone called the exons ‘Junk DNA”, because presumably it has no function; but I suspect that a function will yet be found, perhaps in turning genes on and off.

The DNA resides in the cell nucleus in eukaryotes (in prokaryotes it is dispersed in the cytoplasm, since there is no nucleus), protected by being wound in a super-coiled form around a histone cylinder. Histone is a protein, highly basic to complement the acid nature of DNA. Normally the DNAhistone complex exists as dispersed chromatin in the nucleus, but at the time of cell division (mitosis) it assembles into distinct chromosomes, which are then duplicated and pulled apart into the daughter cells’ nuclei, so that each one has an exact copy of the full complement of genes and exons.

When a gene is “turned on” (i.e. about to be “expressed”) (more about how this is done will be explained in the next section), a protein enzyme called transcriptase copies the base sequence of the gene into the base sequence of a messenger RNA (mRNA). The exons, or nonsense sequences, are excised by special enzymes, and the cut ends are then spliced together like film being edited. The fixed-up RNA then goes from the nucleus into the cytoplasm, where it attaches to an organelle called a ribosome – the real protein factory. Sequences of the bases on the RNA (which strictly correspond to those on the DNA gene from which they were copied) are then translated into the amino acid sequences of the protein being produced.

The ribosome consists of two disk-like parts, and the mRNA runs between them like a tape or ribbon. Each three base pairs constitute a codon, which translates into a particular amino acid. (This genetic code has now been “cracked” and we can read it like a book, routinely.) When a codon has been “read” in the ribosome, a small RNA fragment called a tRNA (transfer RNA) containing this code is sent out to grab an amino acid corresponding to that codon, bring it back and attach it to the growing chain. Thus the protein chain is gradually built up, unit by unit. This mechanism is reminiscent of Turing’s ultimate self-reproducing computer machine, where a tape is read a “bit” (unit of information) at a time by the machine in eventually reconstructing it according to the instructions contained on the tape, while also reproducing the tape for the next round.

The folding of the protein being produced in the ribosome is determined by the amino acid sequence coming from the translation of the genetic information. It is this specific fol<iing which, as already noted, gives the protein its specific enzymatic properties. Enzymes are destroyed by heat, because this “unfolds” or “denatures” them, and they lose their catalytic powers although they still retain the same amino acid sequences.

DNA and RNA also have the ability to duplicate themselves, which DNA does prior to mitosis; the DNA double helix unwinds and the two chains separate, under the influence of enzymes, and on each single strand is built up a new complementary strand from available nucleotide units, so that we end up with two double helixes. The RNA is a single strand to start with; it builds up a complementary chain to itself and then, by building a complement of the complement, it makes an exact copy of itself.

In copying, whether in replication or in transcription, mistakes can occur (as any human typist would appreciate). In the genetic system there are enzymes that “proof-read” the newly produced copy and “correct” it, with a residual error rate of only 1 in a billion, which any human proofreader would envy. These long molecules are not stationary, but rotate, tumble and wiggle with heat motion; and so the faithfulness of copying is like a miracle.

Any mistake in copying would be a mutation, which might be fatal, by making the protein to be formed inoperative in performing its function. Mutations also occur spontaneously, by the action of various kinds of radiation or very reactive chemicals (e.g. oxygen free radicals, thought to be involved in the natural aging process and eventually death). Many of these defects or breaks are corrected or repaired by enzymes that are continuously active to maintain the basic code as intact as possible. However, some remain. The process of entropy is inevitable and unrelenting. (But somehow, cancer cells manage to be immortal !)

Some of the mutations that remain are harmless though not useful; these are tolerated as neutral and ride along with the rest ofthe genome (complete gene collection) to the next generation. They are not eliminated by natural selection because they are not expressed in the visible organism (the phenotype). They are “free riders” in the system, contributing nothing but getting the benefit of replication and reproduction just like the vital contributors. They have been called “selfish genes”.

Other mutations are harmful, even fatal, and these are quickly eliminated by natural selection and do not persist. Then finally there is a very small proportion of beneficial or useful mutations which produce an evolutionary improvement, and they are positively selected and favored in the next generation, finally replacing the original gene. Thus, although mutations are generally harmful or neutral, it is useful for .the organism to maintain a certain optimum mutation rate, in order to be able to adapt to a changing environment and to improve its chances for survival in the face offuture challenges.

There is a balance in all living systems between the tendency to conserve structures that have proved useful and the tendency to retain the flexibility that may be needed for adaptation. On the whole, the genetic system is highly conservative. Some genes and proteins, or at least part-sequences of them, have been conserved unchanged for over a billion years in many diverse creatures, because they code for some essential function. All forms of life on Earth share the genetic mechanisms, and even many of the base-pair sequences are shared all the way from yeast cells to mammals, though the latter have many more genes, and also more “junk” exons. Yet along with the conservation there is the mutation rate – the concession to flexibility, with all the risks that it entails. (Human societies likewise require both traditions and readiness for change, as we can easily appreciate. It is useful to have both conservative and radical political parties and social movements.)

The molecular biology revolution that unravelled the role of genes and the structure of DNA began only some 30-40 years ago, when people realized that the base-pair sequences represent the genetic code. Gradually the “language” became understood. First scientists realized that it was a language or symbolic code, i.e. a way of transmitting information, not just a meaningless chemical structure. Next, they deciphered it like some ancient Rosetta stone and found that they could read it. Now they can rapidly “sequence” any gene or protein, and there is even a mega-project in the U.S. to read and record on computer the entire human genome – billions of base-pairs. It will take years; yet a human couple can initiate its reproduction in the real world in 5 minutes. We shall have the recipe for making human beings just as we are going extinct, probably. Maybe “someone” (?) will be able to reconstruct us from the computer recipe.

The structure of the genetic language is somewhat as follows: Three base-pairs on RNA or DNA form a codon and specify one amino acid of a protein. If a base-pair is like a letter of the alphabet, then a codon is like a word. There are only 4 letters in the genetic alphabet, and the words are all 3-letter words, so the number of possible permutations is 43, which is 64. There are only 21 amino acids, so some of the words represent the same amino acid, and some words are reserved for “punctuation”, such as signalling the start and the end of translation. It must be clearly specified where in the sequence the reading should start, or else the whole message would be “out of register” and totally wrong, i.e. other than was “intended” (by whom? you might ask). Perhaps some words are never used at all.

In this scheme, a gene (many codons, usually thousands of them) would be a sentence or a paragraph or a chapter or even a book; the whole genome would be like a vast library, with (in the human case) 46 shelves analogous to the chromosomes. Actually each cell has all the genes in pairs, one from each parent, and so I suppose there would be 92 library shelves. The exons would be whole rows of nonsense books mixed in among the meaningful books. (Unless we later find otherwise.)

We recognize genetic base-pair sequences as “letters” and “words” (linguistic-like elements) because we are familiar with these in our own human language structures. What would a “non-lingual scientist”, if there could be such a creature, make of them? Would he/she compare/analogize them to musical elements/motifs, like tones and scales? Or visual elements, like beads, chains and networks? Or olfactory elements, which we can hardly imagine, but dogs might? (Dogs recognize individual humans by smell, which probably means that they can smell the MHC complex in which people differ genetically.) All these are information-containing or encoding patterns, which is their common feature and which can be taken in and interpreted by different sense organs and specialized brain centres.

Apparently all humans share 99.9% of the same base-pair sequences, but the commonality is quite a bit lower at the gene level. We are all very largely the same in one way, and yet different individuals in another way. (I wonder how they expect to deal with the variability in the human genome project?) I suppose most of the base-pair sequences specify the structure of organs like kidney, liver, lungs, hands that we all share – hence the similarity. Yet we do have biochemical differences in how we react to drugs or attacks by disease organisms, not only differences in eye color and hair color.

The variability among individuals is especially apparent in the so-called Major HistoCompatibility (MHC) complex, which defines the immunological “self’. The immune system, of course, must distinguish between the self and the non-self (foreign proteins and other antigens), since it must attack the latter and spare the former. More about the immune level will be explained later.

The Epigenetic Level.

All cells of the body contain the entire genome, but each cell uses only some of the genes, the ones it needs for its specific function for which it has been “trained” (differentiated). There are “housekeeping genes” which all cells need and use just to stay alive, but the specialized genes are “turned on” or “expressed” in only some of them. Liver cells or muscle cells or nerve cells only make the specific proteins they need to function as such. Most genes at most times are silent, i.e. “turned off”. What is it that turns genes on and off? These are mechanisms that belong to the epigenetic level, which is not yet fully understood.

There are substances called promoters, enhancers, and inhibitors, which together orchestrate gene expression. Some of these are other genes, some are proteins, some are shorter fragments of one or the other. The inhibitors normally sit on the genes (stretches of DNA) to make them inaccessible to the transcription enzymes, which are also proteins. (proteins of various functions seem to buzz around DNA like worker bees serving a queen bee. This image is appropriate, because the worker bees are also daughters of the queen bee, while the queen bee is the only one capable of reproduction.)

When the gene needs to be expressed, the promoter comes along and removes the inhibitor, giving access to the transcription enzymes. The enhancer can increase the rate of transcription.

The obvious question is: what controls the promoters, inhibitors and enhancers? How do they “know” when the gene products are needed and when the gene should be turned on? If there are some additional genes or proteins involved in regulating the regulators, we seem to be facing an infinite regress. Obviously it is not infinite, since the system operates in the real world in real time. (But recall the Djinns in Hofstadter’s “Goedel, Escher, Bach”, who could reach the last Djinn in an infinite series of Djinns in finite time because the time kept shortening by half each time between Djinns, and the series 1+ 1/2+ 1/4+…has a finite limit of 2.) Perhaps there is a feedback from the cytoplasm that tells the nuclear machinery what is needed. (But see essay “The Master Switch” in Section VIII.)

The epigenetic mechanisms are especially active during embryonic development and during insect or frog metamorphosis, i.e. at times of rapid change. (This is when, in brief bursts, the flexibility tendency overcomes the conservation tendency, i.e. when positive feedbacks of acceleration are more prevalent than negative feedbacks of homeostasis.) Somewhat slower, but still fast changes occur during sexual maturation when sex hormones “kick in”, or the adaptation from river water to sea water in salmon maturation.

No one yet understands in detail how the morphological changes observed during embryonic development and the other rapid changes are triggered at the molecular level, although there are some fragments of knowledge. The epigenetic promoters, enhancers and inhibitors do their “dance” as prompted by positional cues; each cell “knows” where it is located in the developing organism. How does it know” People have postulated hormone gradients, e.g. along the body axis (head to foot), dorsal/ventral, and left/right. What establishes the hormone gradient? Again that hint of infinite regress, but we know that cannot be, it must be a cycle somehow. (But see also “The Master Switch” in Section VIII.)

The whole orchestration of embryonic development, metamorphosis etc. is somehow specified in the genetic blue-print – truly the Holy Writ of life. It specifies not only spatial structures, but temporal sequences as well, in strictly-to-be-followed detail. No wonder it takes a whole library. I have sometimes tried to demystifY genes (which have become modem icons with some racist tendencies) by saying that they merely code for proteins, but they seem to do much more than that; there is a whole superstructure of meaning at the epigenetic level.

Proteins, phospholipids, nucleic acids, glycoproteins~ steroid hormones, neurotransmitters are like some micro-micro-tools, opening pores and channels in membranes for ions and sugar molecules to pass through (or even bigger objects like themselves), sometimes pump-assisted if going up against a gradient like a ship through locks, with tiny phosphonucleotide energy sources powering the pumps or locks. (Energy sources previously charged up by fuel cells in the mitochondria.) The exquisite micromachinery runs in cascades like Rube Goldberg technology, each chemical “gear” or “relay” triggering the next, on down the line, in a multi-jointed chain of causation.

It is a seamless web: DNNRNA makes proteins and proteins control DNNRNA expression, in “chicken-and-egg” fashion. Micro-micro-machinery and holistic organisms are not necessarily opposed images, though often contrasted. However, machines such as cars can be disassembled to repair them, while human bodies must be kept going. (Except for using a heart-lung machine when doing a heart bypass.) On the other hand, organisms are sometimes self-repairing and cars are not. If machinery is closely and minutely integrated spatially and temporally, and if it runs in cycles, it becomes holistic and organismic as an emergent quality. (Our technology and industrial production must imitate this mode in order to become sustainable.)

The micro-micro-machinery of life is also like the printed micro-circuits on computer chips, but still smaller by several orders of magnitude. Of course, we only began to make chips a few decades ago while living structures go back over a billion years; but they probably started from the micro and not the macro erid, building up, not miniaturizing. Some scientists talk about designing tiny drug dispensers circulating in the blood stream to deliver continuously regulated doses of a life-saving drug like insulin. They are getting close to macromolecular dimensions, but are not quite there yet. Building up structures “from below” rather then “from above” should be imitated in institution-building in society.

The Immune Level.

Here again, a great deal of signalling and communications takes place. I am not quite sure whether to place the immune level or the hormonal level first. It seems to be at about the same hierarchical level. (Erich Jantsch did not include this level in his scheme.) In fact, some of the messenger substances of the immune system (the interleukins) operate somewhat like hormones, in that they deliver messages to specific spatially distant target cells; they are just not secreted by endocrine glands.

Since the hormones coordinate systemic functions internally and the immune system acts on external intruders, we could roughly compare them to the department of internal affairs and the department of external affairs in human political state organizations. In the vertical hierarchy, they are both at Cabinet level of the executive branch of government, but they differ horizontally in function.

The immune system consist of cells, antibodies, and messenger substances. The cells generally circulate in the blood and the lymph, and thus have access to all organs and tissues. Macrophage cells swallow foreign intruders in amoeba-like fashion by engulfing and ingesting them. Then they “present” on the outside of their cell membrane the surface markers of the swallowed foreign cells or molecules along with a marker of the “self’ proteins of the MHC complex. The T cells (thymus-trained cells or thymocytes) encounter the markedmacrophages and the surface display says to them: “I am one of us, and I met and swallowed one of THEM, and here is a description of THEM.”

The T helper cells then go into action; they mobilize the B cells (bone marrow trained cells) to produce antibodies to the particular antigen (foreign particle) displayed on the macrophage, and tell the T killer cells to destroy any cells they encounter that display the antigen – not only the intruder cells themselves, but also any “self’ cells that have become infected, say by a virus. This serves to stop further virus reproduction and thus infection of additional cells.

The T cells spread the “red alert” message by secreting interleukins as messenger substances. The system destroys cancer cells (the body’s own “criminals”) as well as foreign invaders, and thus acts as the equivalent of both police and army. (This is where internal and external affairs get mixed up and the analol!V to l10vemment denartments fails.)

The B cells are higWy specialized and come initially in an immense variety; each has an antibody different from all others, so that together they possess antibodies against almost any conceivable antigen difficult as this is to imagine. The alarm message from th~ T cell tells only the specific B cells that possess the antibody against the particular antigen encountered to proliferate rapidly; the others do not take part. The clone of identical B cells from this proliferation then pour out their antibodies in great profusion; they bind to the antigen and neutralize it. Accurate lock-and-key type of fitting is involved in antibody-antigen reactions. Sometimes a less specific “complement”, freely circulating in the blood, is involved, and helps to destroy the intruding antigen (if it is a cell) by cytolysis.

Killer T cells kill their targets by punching holes in the cell membranes so that the semi-liquid cytoplasm leaks out – like a micro-version of a policeman shooting a criminal and leaving him dying in a pool of blood. (National Geographic Magazine once had an article describing these “cell wars” as a parallel to “star wars”.)

Eventually the T cells signal that the counter-attack has succeeded (if it has); the system can be overwhelmed, like any army, especially if it is weakened by drugs like cyclosporin (administered deliberately as anti-rejection agents when surgical transplants are performed), or by the AIDS virus (which attacks T cells), or by fatigue conditions that “lower one’s resistance”. The “stop” signal, when given, stops the proliferation of B cells and the production of antibodies, but it leaves behind a few “memory cells” – B or T cells that will for a long time (sometimes for a life-time) remember the infection and will be able to mount a faster and more effective immune response if the infection is ever repeated. Thus the organism has acquired immunity.

Immunity can also be promoted without the experience of the full disease by using a vaccination serum of weakened, attenuated, or killed virus (or whatever the disease agent is), since the antigen from this weakened artificial infection will look similar to that from the virulent virus when displayed on cell membranes.

The subjective feeling of being sick (the fever, fatigue, headache, loss of appetite etc.) may be due mainly to the effect of the immune response itself rather than the direct effect of the pathogen. A vigorous immune response takes a lot of energy, and so less is left over for the digestion of food or for moving around in vigorous activity. The fever makes the internal environment less favourable for the proliferation of the pathogen. (This group of symptoms, common to many different diseases, has been called “the general stress syndrome”.) So we must gladly suffer the unpleasant symptoms and hope for speedy “victory” of our internal defensive army. A war does demand sacrifices.

However, sometimes the army turns against its own citizens, as in some military dictatorships of our 20th century. Normally the cells that have antigens against “self’ in their repertoire are “deleted” (killed) during their “education” – T cells in the thymus, B cells in the bone marrow. Actually, they are ordered to commit suicide, so called “apoptosis”. This makes less of a “mess” than externally killing a cell, or a cell dying by “necrosis. The “mess” would have to be cleaned up by macrophages, causing “inflammation”. But in apoptosis cells die quietly, neatly, without fuss. However, sometimes this fails and auto-immune diseases develop: the body’s own cells are destroyed. /’

This may happen if a cell’s “self’ marker resembles too closely some foreign marker; this seems to be involved in the destruction of the insulin-producing cells of the islands of Langerhans in the pancreas in juvenile-onset diabetes. Lupus is another auto-immune disease, as is multiple sclerosis, in which the myelin sheaths of nerve fibers are destroyed. Allergies are a milder version of immune system over-reaction – but not always so minor: hay fever is not too serious, but anaphylactic shock (the result of repeated exposure to the same normally non-threatening antigen like lobsters or strawberries) can be lethal, by obstructing the air passages by an exaggerated surface swelling of the epithelium lining the respiratory tract.

The immune reaction also causes the rejection of transplants, both of tissues or of whole organs. Unless these come from the patient’s own body, as is often done in the case of skin grafts performed in burn cases or for cosmetic reasons. Grafts from an identical twin are also not rejected, since identical twins are genetically the same, i.e. have the same MHC complex. To perform transplants from foreign donors, immuno-suppressive drugs such as cyclosporin must be given, a treatment which makes the patient more susceptible to infections.

The Hormonal Level.

Hormones are substances secreted by the endocrine (internal secretion) glands (pituitary, adrenal medulla, adrenal cortex, thyroid, testes or ovary, corpus luteum, islands of Langerhans, etc.) directly into the blood stream, and conveyed by the latter to target cells, tissues or organs to initiate or promote or inhibit a variety of functions and reactions.

The pituitary is the “master gland”, secreting hormones which prompt other glands to start secreting. (This includes the adrenal glands and the gonads.) The adrenal medulla produces adrenalin, also called epinephrine, which acts in the “fight or flight” reaction when the organism is in some external danger, e.g. from a predator or an accident. The adrenal cortex produces cortisone, which reduces inflammation in tissues. The thyroid gland produces thyroxine, an iodine-containing tyrosine derivative which speeds up the metabolic rate. (Shortage of iodine produces hypothyroidism or goiter, while overproduction of thyroxine or hyperthyroidism causes weight loss.) The gonads (testes or ovaries) secrete various sex hormones, which regulate sexual and reproductive functions. The islands of Langerhans secn,;te insulin, which regulates the metabolism of carbohydrates; its shortage produces diabetes.

How do the hormones deliver their “messages” at the cellular level? This is a very active area of research. Hormones and the related growth factors (e.g. nerve growth factor) act through elaborate cascade mechanisms, at two levels:

1. the action of hormones from some glands on other glands to influence their secretion, and
2. at the intra-cellular level, by producing “second messengers”.

A good example of the first type of cascade is the secretion of ACTH (adrenocortico-tropic hormone) by the pituitary gland, which in turn stimulates the secretion of cortisone by the adrenal cortex; the cortisone then controls other processes and functions, especially anti-inflammation mechanisms.

The pituitary also controls growth and maturation, through other cascades. It stimulates the testes of the male to produce androgens such as testosterone, which give rise to secondary male characterics such as facial hair and voice change; and the ovaries of the female to produce estrogens, which control the female estrus cycle. At one stage of this cycle, the corpus luteum which remains behind after ovulation (release of the ovum into the Fallopian tube) starts secreting progesterone, which acts to maintain pregnancy if the ovum has been fertilized.

Hormones also act in cascades at the cellular level. Their target cells (those that receive the message) have protein-type receptors in their cell membrane into which the arriving hormone molecules fit like a key in a lock. This binding of the hormone alters the structure of the receptor in such a way that it activates other molecules inside the cell cytoplasm, such as a protein kinase (an enzyme which can phosphorylate a given protein and thus activate it) and a G-protein. This chain reaction or cascade eventually produces cyclic adenosine monophosphate (cAMP), which acts as a “second messenger” (the hormone itself being the first messenger). In many cases, calcium ions are also involved, being admitted into the cell by the opening of a specific ion channel through the action of the same cascade. The cAMP then effects the functional change that is required – constriction of blood vessels or whatever.

Hormone cascades of both types described above are obviously signalling or communication sequences. The cells in an organism interact continually; adjacent cells often through their intermembrane junctions directly, distant cells through hormone messages delivered through the blood – the common carrier which is like a combination of mail and telegraph services. The cellular cascade is then a way to read the message and act on it, executing the order which it contains. By means of this communication network, the whole organism can act in a coordinated way. The differently specialized (differentiated) cells of pancreas, muscle, mucosa etc. are integrated in their functions.

Since growth factors are related to hormones, we can postulate one way in which unrestricted cancer growth may be initiated. If an altered or abnormal growth factor is bound to a cell membrane receptor, or if the receptor itself is abnormal, the growth factor, which is usually removed by enzymes after it has delivered its “message”, i.e. begun the cascade, can become “stuck” and continue to stimulate growth which then cannot be stopped. This can be visualized as the growth factor becoming truncated so that the part on which the stopping enzyme would act is missing, or else the receptor has become altered so that it hangs on to the growth factor too tightly. The abnormal growth factor or receptor would be one made by a mutated oncogene, some of which have been identified. It is somewhat like the Sorcerer’s Apprentice knowing only the initial order to the broom but not the stopping order.

Hormonal communication between cells is efficient, but slow. The effects occur in minutes or hours or days, depending on the case. For fast communication we need an up-graded technology – the nervous system. This is like going from surface overseas mail to telephone or fax.

The Neural Level.

At the neural level (the last biological level we shall discuss), the messages are delivered in seconds or fractions of a second. Like telephone or fax, these are electrical impulses, but really electrochemical in their detail. The primitive nervous system was at first slower than the “state-of-the-art” system in higher vertebrates, because its message-carrying fibers (nerves) were not “insulated” and so electric charge could leak out of them. Insulation was later introduced in the form of myelin sheaths around nerve fibers. In multiple sclerosis, the myelin sheath comes under auto-immune attack, leading to severe disruption of normal communications.

Humans and higher vertebrates have three nervous systems: the sympathetic, the parasympathetic, and the voluntary. The first two are sometimes grouped under the name “autonomous” or “autonomic”, as opposed to the third, the “voluntary”. The sympathetic and the parasympathetic systems tend to counterbalance each other. The sympathetic causes activation, mobilization, arousal similar to the action of the hormone adrenalin, which mediates the “fight or flight” reaction in situations of danger: constriction of the peripheral blood vessels, faster heart beat, conversion of glycogen to glucose in the liver and muscles, etc., all designed to mobilize the body for rapid action. The parasympathetic system reverses all these effects, and so tends to counterbalance the sympathetic. Without it, we would remain permanently excited after the danger has passed – a state of chronic anxiety from which some people suffer to the detriment of their health – a cause of several psychosomatic diseases.

The above is a horizontal classification of the nervous system. Vertically there is the peripheral and the central nervous system (CNS); the latter consists of the spinal cord and the brain, the former of the afferent fibers which bring in messages from the sense organs and the efferent fibers which send orders to the muscles, not only the skeletal muscles for locomotion (which are under voluntary control), but also those involved in heartbeat, digestion, breathing and other functions, which are in the province of the autonomic nervous system.

The smallest elements of the nervous system are the nerve cells or neurons. Each consists of a cell body, afferent branched dendrites which receive the signal, and a long straight axon which conveys the signal. The signals or messages pass from the axon of one neuron to the dendrites of the next neuron through a small gap called the synapse.

The axon releases a neurotransmitter, such as acetylcholine, epinephrine (adrenalin), norepinephrine, dopamine, glutamate, serotonin and others, from subcellular vesicles which merge with the cell membrane and turn inside out to empty their contents into the synapse. (This process is called exocytosis.) From there, the neurotransmitter is picked up by the dendrites of the next neuron and conveyed to its cell body for further action.

The signal may be excitatory, i.e. tending to make the second neuron “fire” (emit a neurotransmitter into its efferent synapse) or it may be inhibitory, making it less likely for the second neuron to “fire”.

The “firing” of a neuron is an electrochemical event in which the initially electricaltY polarized cell is depolarized, or its polarity is actually briefly reversed, by an instant inflow of potassium ions when the potassium channel in the membrane is opened by the action of the neurotransmitterJrom the preceding neuron, and then the pore is again quickly closed. The result of “firing” is a brief pulse which then travels down the axon to the next synapse, to communicate the signal to further neurons down the line. Note that this is a digital signal like that on a computer; a neuron either fires or it does not (no gradations in between); it is 1 or 0, yes or no.

After performing its task, the neurotransmitter is quickly cleared from the synapse cleft by decomposing enzymes. For example, acetylcholine is split into choline and acetate (both inactive) by the enzyme choline esterase. So-called nerve gases (chemical warfare agents) interfere with the action of choline esterase; as a result, acetylcholine accumulates and causes permanent muscle spasms, convulsions and death. The only antidote is atropine, also a poison but of opposite effect, so one must use precisely the right amount. Nerve gases are phosphorus compounds very similar to certain insecticides, which act in a similar way on an insect’s nervous system.

The nervous system is used both for internal regulation like hormones, and for external interaction like the immune system. The three levels are closely related: interleukin from the immune system is like a hormone, while adrenalin is both a hormone and a neurotransmitter.

We can imagine that the hormonal and immune systems evolved gradually from the. epigeneticusing a similar type of cascades and balanced counter-actions of promoters and inhibitors ~ and that the nervous system gradually evolved from the hormonal and immune by greatly speeding up the reactions and transforming them from an analogue to a digital type of operation.

The internal actions of the nervous system were already mentioned in the case of the vasorestriction effect of the sympathetic nervous system, for example. The autonomic nervous system also regulates the heart -beat, breathing rate, digestion, and many other functions beyond voluntary control. Locomotion, and muscle action in general, is under voluntary control.

But how meaningful is this distinction? We shall not here engage in the philosophical debate about free will and determinism, but there are some considerations of a more empirical natute that tend to blur the distinction between voluntary and autonomic neural control. By bio-feedback methods, people have been trained to control their heart-beat rate and surface temperature, and in some Eastern mystical religious cults, such training is commonplace. On the other hand, it has been shown in psychological experiments that the physical impulse to move one’s hand precedes in time by some microseconds the conscious decision to do so (described by Dennett). There are some complex cross~vers between the voluntary and the autonomic neural mechanisms, showing that there is not a sharp distinction, but some overlapping continuum.

Among the most important tasks of the nervous system is the maintenance of contact with the external environment through the sense organs. Very large areas ofthe brain are devoted to this task. The sense organs (eyes, ears, nose, taste buds, skin) are in essence transducers of signals (light, sound, chemicals, etc.) into nerve impulses which the brain can interpret; but the interpretation involves complex computations, like some CAT scans invented by humans; it is not a simple matter like taking a photograph of a visual scene, for example.

The interaction of the organism with the environment also, of course, involves outgoing signals, which in turn translate into acting on the environment. The transducers for this action are primarily the skeletal muscles, which not only transform, but greatly amplify the energy of nerve impulses into kinetic energy of motion through chemical energy transformations. The inputs from the sense organs and the outputs by the muscles can be linked by a “reflex arc” through the spinal cord – a short circuit which bypasses the brain – or they can be routed through the brain for further consideration (“sober second thought” like legislation going to the Senate before being enacted into law). The reflex arc is used when speed of reaction is essential, like withdrawing one’s hand from a hot stove. The full brain circuit is used when there are several good choices or options.

The intermediate stage is the “conditioned reflex”, like Pavlov’s experiment with dogs salivating when the bell rings which has previously been consistently associated with the bringing of food. The conditioned reflex is the basis of certain theories of learning and memory (e.g. B.F. Skinner), and the whole behaviourist school in psychology which tries to reduce everything to “stimulus and response” patterns, implicitly or explicitly denying the reality of the intervening mental states. (At least it insists that mental states are not available for empirical investigation and thus lie outside the sphere of science.)

In any case, it is clear that we are beginning to cross here in our discussion from the field of physiology to that of psychology. However, inter-disciplinary lines should be seen as blurred in the same way as the boundaries between levels or between different parts of the nervous system.

We cannot go into details of sense perception or muscle action here, just as we could not cover all aspects of hormone action (omitting e.g. the regulation of the estrus cycle and of pregnancy, or the insulin-diabetes connection), or of metabolism (omitting details of food digestion and absorption). Each of the “levels” we are describing represents vast fields, which have been studied for decades or more by specialists and about each there is a prolific literature. Mainly we are trying to get a bird’s eye view of the levels and get an overall impression of each and of their interactions and overlaps. We shall not stop at the neural level, but try to go beyond it, linking biology with sociology.

At each level so far, we observed communication between cells and their products or sub-units: enzymes, genes, promoters and inhibitors, antibodies, hormones, neurotransmitters. Now let us look at communications between human individuals in societies, which are also Millerian living systems, though far less completely integrated. But before we discuss the human mode of communication, which is predominantly and typically through language, let us look at some predecessors of this mode. How do various animals and plants communicate?

The Pre-linguistic Level.

Animals often communicate with each other through their sense organs. Male insects are attracted to females by pheromones, chemical “smell” attractants whose name was deliberately coined to rhyme with “hormones”. The sense of smell is used widely in animal communication. Wolves mark the boundary of their territory with their urine, whose smell identifies them individually since their nose is sensitive and discriminating enough for this task. Dogs, who are related to wolves, also have a keen sense of smell, probably using it more than sight or hearing. How different their world must be from ours! Our sense of reality is not the only possible or the only existing one, which should make us humble. 1 almost said, above, “their IMAGE of the world”, until 1 realized that this is a visual term coming from our own experience.

Bees communicate by their famous “waggle dance” (which is visual communication), to tell their colleagues where rich food sources are located. We are not sure how whales communicate; their “songs” may be a way, or they may be an expression of joy and beauty, like our art forms. Birds mark their territories by the sound of their songs, bats use sonar. Crickets and cicadas attract sexual partners by the sound of their chirping, generated by rubbing their legs together. Some plants (angiosperms) use lavish displays of colourful flowers to attract pollinating insects visually. Some butterflies and toads even advertise to their potential predators that they are poisonous and inedible; sometimes this is fraudulent advertising, through mimicking the colours of the truly poisonous species. Perhaps these examples will suffice.

Animals, including humans, use body language for communication; gesture with hands or faces, smiles and frowns, nodding or shaking your head for “yes” or “no”, slightly turning your body left or right as you walk through a crowd to signal which way you intend to pass – all these are body communications. Many of them among humans are transcultural; e.g. smiles indicating friendship or joy. Others differ rather sharply across cultures, and one can quickly get into trouble when travelling in a foreign country by having one’s signals misunderstood.

Sounds such as grunts and coos, whistles and yells can be used for signalling and conveying meaning. (I often wish that car horns had distinctive sounds at least differentiating anger from warning from “hi there”.) This has been shown to be the case in macaque monkeys, among whom a mother can tell when her offspring is in serious trouble or when he/she is merely engaged in rough play with other youngsters; the cries uttered have a distinctly different quality. This surely is also the case with human children; however, there it is supplemented very early on by language, when the tearful child announces between sobs “He hit me first!”

The Linguistic Level.

Language is a human invention, though perhaps not unique – we do not know enough yet about whales or dolphins and some apes and monkeys. A gorilla named Washoe has been taught American sign language and knows the meanings of over 100 words, like a small human child. There has been speculation whether she would teach sign language to her offspring. Apes cannot use voice )anguage, because they lack the physical apparatus for articulated speech sounds in the throat and mouth. However, Washoe can use signed words to make her wishes known (ask for special foods at various times etc.) and put words together in sentences of primitive grammatical construction. Other instances of apes,learning sign language are known.

True language, unlike other sound signals such as grunts and cries, can express entire concepts and ideas. The words of a language are symbols (something that is an arbitrarily defined stand-in for something else), not only signs like a cry of alarm or warning or a purring indicating pleasure. Humans not only have the brain capacity to formulate concepts and ideas, even quite abstract ones (sometimes too abstract), but also the physical apparatus (lips, palate, tongue) to create the required sound modulations, to utter the symbols and send them out on sound waves for other humans to hear and interpret. There are specific areas in the brain specialized for language production; in some cases of stroke these may be destroyed, and these patients lose their faculty of speech, although the physical apparatus is undamaged, and they can also still write down their thoughts in words.

There was a price to pay for having the physical mouth and throat parts for speaking. Because the voice box had to be higher in the throat, the trachea (tube to the lungs for breathing) and the esophagus (tube to the stomach for eating) are joined at the top, somewhat compromising the swallowing apparatus. Every now and them someone chokes when food goes down the wrong way.

Most experts (including Noam Chomsky) think that certain linguistic rules (how words are put together into sentences) are innate in humans, i.e. genetically programmed. If this is so, it would be truly amazing – the far reach across almost all the levels that we have outlined here.

The rules for correctly assembling words into sentences is called grammar. Some of its rules are common to all the thousands of languages spoken in the world; e.g. the sequence of subject – predicate object (noun – verb – noun, or “who does what to whom”), with adjectives modifying the subject and object and adverbs modifying the predicate. There are then higher-level rules for properly combining these simple sentences into complex sentences by means of conjunctions and punctuation. All this a child learns without explicit instruction, by simple imitation of adults. (The next three paragraphs repeat what has been said in the essay “The Three Essences” in Section II.)

However, a grammatically correct sentence can still be “nonsense” semantically, i.e. not express any meaning. Any example will do: e.g. “The joyful house jumped over deep thoughts.” Sometimes poets use such sentences at the edge of semantic chaos, to convey existential moods; but in ordinary or scientific discourse they are not used.

Even a semantically meaningful sentence may violate the rules of logic: e.g. “I am a woman and you are a woman; therefore all humans are women”. The conclusion here does not follow from the premises. Even if logic is not violated, a sentence can still be false rather than true, if one of the premises is false (not corresponding to reality). E.g. “since grass is blue, it must contain a blue pigment”.

Thus a sentence, to qualify for meaningful discourse, must pass through four successive sieves: the grammatic, semantic, logical, and truth criteria. In normal quick conversation, we do not even think about these complications, but chatter away with abandon, not aware that we are doing something quite complex and special. We do sometimes say things that violate logic and truth, and may be corrected for this; but we are considered really weird and in need of psychiatric attention if we consistently talk nonsense; and Chomsky would say that not even the youngest child utters sentences that are ungrammatical.

The linguistic mode of communication that we have been discussing is at the oral-aural (mouth to ear) level. The so-called “oral tradition”, practised in all traditional cultures for millenia, probably goes back to the origins of modem people some 200,000 years ago. It is still carried on in many places. Whole legends of origin, stories, and religious rites and ceremonies are memorized and passed on from generation to generation. Cultural transmission of “memes” has been compared to the biological transmission of genes.

The great emphasis on memory (and therefore the required excellent memory training) and the immediacy of the rapport between the story-teller and the audience were culturally valuable traits, and there has been much regret expressed at the passing of the oral tradition when it was superseded by the next, the literate level. This is reminiscent of present-day complaints at the decreasing importance of reading books and their replacement by television, and now the Internet. We always regret abandoning the past and going into something new. However, I do not mean to imply that television is at a higher evolutionary level than books. We simply do not know yet.

The Literate Level.

The invention of writing is much more recent in human history than the invention of language, going back to the beginning of recorded history, perhaps 3000 years ago. Many people today are still illiterate, and world organizations like UNESCO and World Literacy are trying to promote reading and writing skills among preliterate people.

The switch from the oral to the literate tradition meant changing from mouth-and-ear to handand-eye, from the auditory to the visual sense. It meant inventing a whole new set of symbols – letters standing for vocalized phonemes. Originally there were, in some systems of writing, symbols for whole words or concepts (Egyptian hieroglyphics or Chinese characters), the symbols often being like sketchy pictures of the objects represented. Eventually the use of separate letter symbols for each phoneme was found to be more useful and parsimonious, because far fewer written symbols had to be learned and memorized by the user.

By using combinatorial methods, one can always easily construct awesome complexity from a small number of elements. Remember, the genetic code has only four letters, the musical scale has only 8 tones (“notes” in writing), hundreds of thousands of chemical compounds can be made from only about 100 elements, an infinite series of numbers is composed of ten digits (in fact two would do in the biruuy system) – and the English alphabet has only 26 letters to make tens of thousands of words in our dictionaries. Yet these systems based on a small number. of elements can generate whole complex organisms, beautiful symphonies, arrays of crystals, the whole edifice of mathematics, and all the great works of literature. Emergent qualities? You bet!

The same emergence of greatly increased variety is observed when we go from words to sentences. The number of words in a language, though vastly greater than the 26 letters, can still be put into reasonably-sized dictionaries, but the number of sentences that can be formed from words is virtually infinite; or at least, from the human point of view, inexhaustible. The flexibility of these systems formed from a small number of elements and gradually assembled in successive hierarchical levels is truly amazing.

The Technological Communications Level.

The first step in the series of new communications technologies was the invention of the printing press in medieval Europe. This enabled people to go from the laborious copying by hand of a few important books (like the Bible by monks in monasteries) to the quick machine production of any required number of copies. Along with Luther’s Reformation, this put the Bible into the hands of ordinary people (at least the literate ones), no longer limiting it to the priests. Other books quickly followed, catering both to serious learning and to entertainment. It was a true democratic revolution, the first in a series.

It has been said that while the printing press made every person a reader, the invention of photocopy machines made every person a publisher. Every office can now produce multiple copies with ease. The progression went from lithographic printing to mimeo or ditto machines to Xerox, each time making the process easier and less demanding. Again it was a democratic tool: the old Soviet Union tried to prohibit private use of these machines, which could be used for subversive propaganda by dissidents, but the effort was unsuccessful. Samizdat presses flourished and the Soviet Union, a world superpower with awesome destructive potential, disintegrated.

Telephones can carry human speech over any distance on the Earth, and telegraph (now almost outmoded), Telex, Fax, and e-mail via computer can similarly carry the written or printed word or pictures or graphs (even in colour) to any place in the world that has the receiving machines. (I almost said “receptors”!) In the oral tradition we have audio cassettes, record players, radio, CD ROMs, and other devices. Ordinary consumers do not understand how they work, but anyone (especially children) quickly learn how to use them. Television and VCRs combine the aural and the visual aspects.

These technological advances are too recent to chart. They are still evolving at an extremely rapid rate (since cultural evolution is so much faster than biological evolution). If you bought a computer ten years ago, it is probably obsolete today. (Even this statement, written 4 years ago, is obsolete: A recent T-shirt proclaimed “While you were reading this your computer became obsolete. “) The social impact of the new communication technologies is still controversial. Perhaps we are changing too fast, need to stop and take stock. While evolution means change, it must be built on a careful consolidation of previous levels, so that the new level being created does not collapse for lack of a solid foundation.

The February 1997 issue of Scientific American contains a comparison of the rates of biological and technological evolution, concluding that the latter is 10 million times faster (See W. Brian Arthur).

Is There an Extrasensory Level?

Many instances of telepathy, clairvoyance, “spoon-bending” and other mind-over-matter phenomena have been reported, from ancient times to the present. Scientists are still skeptical, perhaps unjustifiably. Why is it that they investigate all these claims so strictly for fraud, when we usually trust mainstream scientific experimenters in traditional laboratories not to cheat? (Some of them have cheated, in fact.) There seems to be a double standard here.

Also, the failure to replicate results in extra-sensory perception (ESP) experiments may be due to the fact that some persons possess this ability while others do not, like some people having musical ability or mathematical skills in greater abundance than others.

Finally, scientists are reluctant to admit the possibility of ESP because they cannot think of a mechanism for it; but then, we do not know what gravity or electricity is, either. We merely give it a name.

Are all people, not only those presently living, but also all our ancestors, tied into a great communications net which Jung called the Collective Unconscious? Again we do not know.

In any case, we can envision the whole scheme of intertwining levels (some of them temporal evolutionary stages) in the succession we have traced here. Much has been left out at each level, and the level of artistic creation was not even mentioned. Nevertheless, the emergence of Mind from Matter is made apparent in this sequence, and the story is not over yet.