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From Crystals to Crocodiles
GA 347

VI. The processes of digestion in physical as well as soul-spritual terms

16 September 1922, Dornach

To complete our picture of the human being, let's look more closely at what is going on every day in our body when certain processes take place. After all, we can understand more complex processes only after we have learned about the basic ones. This is why I want to discuss again the processes of nutrition in both their physiological and psychological aspects.

When we eat, we take in food through the mouth. We take in both liquid and solid substances, and by inhaling through the lungs we absorb gaseous ones. But our body can assimilate and use only liquids. Therefore all our solid food must be liquefied already in the mouth. This is accomplished by small glands in our mouth and palate that constantly produce saliva. You must picture them everywhere in the mouth cavity, even along the edge of the tongue. Seen under a microscope the salivary glands resemble small grape bunches because they consist of a cluster of many adjoining cells. They produce saliva, which in turn must dissolve and permeate all food in order to make it digestible.

We perceive this insalivating and permeating activity with our sense of taste. During insalivation we taste the food. Just as we perceive colours with the eyes, so we perceive the flavour of food with the sense of taste. So, what we eat is insalivated and tasted, savoured, in the mouth. Through our sense of taste we become aware of what we eat. The insalivating process prepares the food for further processing and absorption by the body. But in order to achieve this, the saliva must contain a certain substance called ptyalin, which is produced by the salivary glands and transforms our food so that the stomach can then process it further.

Once our food has been insalivated and permeated with ptyalin, it enters the stomach through the oesophagus. There the food has to be processed further, and for this another special substance is required. This substance is produced in the stomach, just as saliva and the ptyalin it contains are secreted in the mouth. Our stomach, then, produces another kind of saliva that permeates our food. The special substance contained in this saliva is called pepsin.

You see, after the age of seven we no longer have any sense of taste in our stomach. But infants can taste their food there just as adults taste theirs in the mouth. In order to truly understand the human being, we must study the infant's soul life. Adults can at most get an inkling of what it is like to taste in the stomach when this organ is upset and moves the food upwards instead of moving it down into the intestines. Then they get an idea that taste can be perceived in the stomach. I assume that at least some of you have had this experience that food that had already been in the stomach then comes back into the mouth. You will remember that it really tastes much worse than everything we eat, or at least most of it anyway. Foods tasting like what comes back up from the stomach would certainly not be considered a delicacy.

Now this unpleasant taste must have originated somewhere. Well, it started in the stomach. In our mouth the food is liquefied and then merely permeated with ptyalin. In the stomach it is further saturated with pepsin, and that is why it now has a different flavour.

There's more to our sense of taste than is immediately apparent. Let's assume you are very sensitive and drink some water. Unless the water has been spoiled, it will not taste bad at all. But if you have eaten a lot of sugar right before that, your tongue is attuned to that flavour, and the water will taste sour. You can see that our sense of taste is quite a complicated thing. However, taste as we adults know it does not originate in the mouth, but in the stomach. Children feel but don't think yet, and that is why they don't know what tasting with the mouth is like. Therefore infants must be given food that does not taste too bad in the stomach. Mother's milk, or also milk in general, is such a food, simply because it does not have a bad flavour in the stomach and because there is a kinship between babies and mother's milk. After all, children are born out of the same body that produces the milk. Because of this relationship between the milk and the baby, the milk does not taste bad in the child's stomach, but if we were to feed infants other food too early they would find those foods repulsive. As adults we don't object to those foods any more because our sense of taste has become coarse. To infants such food would be repulsive because they have no kinship withy them. Thus next to ‘stomach’ I can write ‘child's sense of taste’ [see list on page 87].

To return to the food substances in the stomach, once they have been permeated with pepsin, they enter the duodenum, the small and the large intestine and so forth. If the chyme simply stayed in the intestines without further processing, it would become hard and destroy us. So something else has to occur, a new activity proceeding from yet another gland. As you know, we have glands in our mouth and in our stomach, and we also have a large one behind the stomach. It is called the pancreas. It secretes a kind of saliva that flows through delicate vessels into the intestines. There the chyme is permeated by this third liquid.

The substance produced by the pancreas is actually transformed in us. At first it closely resembles the pepsin produced in the stomach. On its way towards the intestines, however, it changes. It becomes more strong and pungent, for at this point the chyme must be worked on more strongly than before. This pungent liquid secreted by the pancreas is called trypsin. In other words, the pancreas produces a liquid that becomes trypsin, an acrid substance, in the intestines. It is the third liquid permeating the chyme.

As I said last time, our head-centred consciousness no longer perceives the processes the chyme undergoes. Instead they are perceived, tasted or felt by the liver and thought by the kidneys. The liver and the kidneys have soul qualities and are able to perceive just as we perceive with the sense organs in our head. We are not aware of the liver's and the kidneys' perceptions except, as I said, in dreams; then these perceptions are expressed in a pictorial way. For instance, the chyme advances through the winding intestines and is permeated with trypsin. This acts as a stimulus and can trigger dreams of snakes. At a soul level the perceptions of the liver are thus transformed into something vague and unclear.

So, the liver perceives the processes involving ptyalin, pepsin and trypsin. I'm sorry, but I have to use these dreadful terms scientists unfortunately have coined. Today's so-called experts resent all attempts to clarify things, and they would really be shocked if we gave new names to these substances. We could do this, of course, but I will refrain from shocking scientists unnecessarily with new terms and go on using the old names ptyalin, pepsin and trypsin. The chyme is insalivated three times by three different liquids. These activities are connected to liver perceptions [see list below].

Now, gentlemen, let's try to understand how these liver perceptions take place. As an analogy, think of what happens when you hold a raw onion to your nose. Your eyes water, don't they? If you hold horseradish close to your nose, your eyes fill with tears too. Now why is that? Your eyes water because horseradish and onions work on the tear glands that then excrete bitter tears. The effect of horseradish and onion on the tear glands is roughly like that of the chyme on the liver. The chyme moving through the intestines causes the liver to secrete a kind of tears, namely, bile. The onion must be perceived, must be felt, if it is to cause the production of tears. Similarly, the liver perceives the chyme and adds the bile it has secreted. This then is the fourth liquid our body produces:

Mouth: sense of taste—ptyalin
Stomach: child's sense of taste—pepsin
Pancreas: liver perception—trypsin
Liver: bile

After the chyme has been permeated with ptyalin in the mouth, with pepsin in the stomach, and with trypsin through the pancreas, the liver finally adds bile to it. Only at that point does thinking in the kidneys occur.

After having been permeated by four different liquids, the chyme is absorbed through the intestinal walls into the lymph vessels and then into the blood. You see, then, that very complex life processes take place in the human body. All the way from the mouth to its final absorption by the blood, the chyme is constantly being transformed so that it can be digested properly by the stomach as well as by the entire body.

Now, gentlemen, if we tried to duplicate these processes in a laboratory, even if we were very clever professors, we couldn't do it; we wouldn't be able to duplicate the processes of digestion. We would have to chew the food to permeate it with saliva, then we'd have to saturate it with the liquids produced by stomach, pancreas and liver. Obviously, we wouldn't be able to do all that in a lab; yet these processes are always going on in us, every day of our life. True, we are quite intelligent, but the processes in our belly show much more intelligence than people usually have. The digestive processes are organized very wisely and are not at all easy to duplicate.

You will have even more respect for these processes when I describe them in detail. What do we usually eat? Well, we eat food made from plants, animals and minerals. So there is a wide variety of substances that enter our mouth and then our stomach and intestines, and all of these substances must be transformed through the various processes of insalivation I described.

For instance, think of potatoes. What do they consist of? They consist mainly of starch. When we eat potatoes, we actually eat starch. It is one of our main foods. Potatoes consist almost entirely of starch and of the liquids permeating it, especially water. Because of its contents and the strong life forces in it, the potato looks the way it does. It is actually living starch, which must be destroyed in digestion as I explained. Starch is also contained in other things, not only in potatoes. In fact, all plants contain starch, and we eat starch when we eat plants.

What else do we eat? Whether we eat food from the plant or the animal kingdom, we also take in protein. We also find it in eggs; there it is in its pure form but already somewhat 'deadened'. So we eat protein, as part of meat or plants. We are always eating protein. It is the second most important food.

In addition to starch and protein, we also eat fat. Although there's more fat in animals than in plants, there are certain plant fats. In order to be properly nourished, we need plant or animal fats. They are our third most important food. Our fourth major food is salt and other minerals. We must either eat foods containing sufficient amounts of salt and minerals or put a salt shaker on the table so that we can add salt to our food because our body needs it. All of these substances end up in the intestines and are transformed there. Well, and what becomes of them? Because the food substances have been well prepared by saliva and the digestive juices in the stomach, they can be insalivated a third time in the intestines; they won't harden there but will be transformed.

Starch: sugar
Protein: liquid protein
Fats: glycerine, fatty acids
Minerals: minerals

What becomes of starch in digestion? It is transformed into sugar. In other words, when we eat starch, it becomes sugar in the stomach. If we want to have sugar in us and if we could produce enough of it ourselves, we would not need to eat any for the simple reason that we could manufacture it from starch. But although it is in our nature to be able to do a lot of things, we are not omnipotent. Thus we do not produce enough sugar, in some cases far too little. In order to complement what the intestines themselves normally produce, we must add sugar to our food. To sum up, our intestines transform starch into sugar, which is quite an art.

As you know, people prone to digestive problems find that soft-boiled eggs agree with them better than hard ones. Of course, eggs that have started to rot certainly do not agree with us. Protein is good for us, but if it is still alive when it enters our intestines, it would become unusable and fetid in us, too. We can't use it in our intestines in the form it has outside us. The protein must be transformed first; above all it must be dissolved. It won't dissolve if you merely put it in water. It takes more than just water to dissolve protein. In particular it is trypsin, more than any other liquid, that can liquefy protein.

During this transformation, another substance is formed in our body as a result of the activity of the liquid produced by the pancreas. Strangely enough it is alcohol that develops there. Yes, we produce alcohol in our body. So, we don't really need to drink any alcohol because we are constantly manufacturing it in our intestines. It is only when the liver gets too greedy for alcohol and won't be content with perceiving the small amount of it produced in the intestines that people become alcoholics.

Some people have always known about this and used it to argue in favour of drinking wine and beer. They would argue against teetotalers by saying that we cannot possibly abstain totally from alcohol simply because we all produce some of it in our intestines. Well, this certainly doesn't justify becoming a drinker and demanding an excessive amount of alcohol. If we drink too much alcohol, in other words if we give in to the liver's greed for it, our liver will degenerate into proliferous growth.

After all, the liver has to function properly. If it keeps growing, the small glands in it begin to swell, and then the Ever can no longer produce bile of the quality needed. Therefore the chyme is no longer properly permeated with bile and enters lymph and blood vessels without having been properly digested. This imbalance then reaches even the heart and affects it. That is why the liver of people who drink too much beer and so on is ill and looks quite different from that of people who rarely drink or who are content with the small amount of alcohol produced in their own intestines, which should essentially be enough anyway. Liver and heart disorders result from excessive alcohol consumption. That is why a large number of people in Munich have a so-called beer heart.1Translator's note: The German city of Munich was (and still is) famous for its beer, which is consumed in great quantities by the population, particularly at the world-famous annual Oktoberfest. Of course, their liver is also damaged for the same reason. You see, we can understand various malfunctions and diseases by examining what happens to the chyme in our organism, by studying the digestive processes.

So when protein is liquefied, alcohol forms and permeates the protein; this prevents the protein from rotting. As you know, if we want to keep something from deteriorating we put it into spirits; for alcohol acts as a preservative. Thus the organism itself can preserve protein by permeating it with the alcohol it has produced. A very wise arrangement, isn't it?

We could not get the same results if we tried to duplicate these complicated processes that occur within us. For instance, if we want to preserve a human organ or a small organism, we put it into spirits and display it in a scientific exhibit. But the trypsin fulfils this function in a far more delicate and intelligent way in our intestines. It produce alcohol and uses it to permeate the protein.

And what happens to fats? Well, gentlemen, they enter the intestines and are transformed by both trypsin and bile. Two substances develop out of fats. One of them is glycerine. You already know it in its commercial form; we also produce it in our body. In addition to glycerine, various kinds of fatty acids form when fats are transformed in digestion. Only the salts and minerals undergo little change. They are merely dissolved for easier digestion. They remain basically as they were in the food we ate; they remain unchanged [see list on page 89].

Thus when we eat, we take in starch, protein, fats, and minerals. Once we have digested them, they have turned into sugar, dissolved liquefied protein, glycerine, fatty acids, and salt and minerals. What happens then to these transformed substances? Remember, they are now different from the ones we ate. Our organism has changed them. Well, you see, a few centuries ago, there was a doctor in Switzerland who had an idea about the digestive processes I have described. Yet modern scientists despise him. His name was Paracelsus, and he was a professor in Basel.2Paracelsus, actual name: Philippus Aureolus Theophrastus Bombast von Hohenheim, 1493-1541. German alchemist and physician. First to introduce minerals and metals as medicinal substances. Expelled from the University of Basel for defying traditions, for instance by lecturing in German and criticizing classical writers. But people there sent him away because he knew more than they did. Even today he is still scorned. Although he was a very intelligent person, he fell off a cliff and fractured his skull. Had he been what is now called an honourable citizen, for instance a city councillor, people would still honour his memory. But he was a person who knew more than others. So they called him a drunkard and said that was why he fell off the cliff. Well, that's how the world goes. As I said, he knew a lot and always strongly emphasized these transformative forces in us. But during the centuries since his time this has been all but forgotten.

To return to my previous question, what happens to these transformed substances in us? In this respect modern scientists labour under a great delusion. They say that substances such as sugar, liquefied protein, alcohol, glycerine, fatty acids and minerals all enter the blood vessels, through them get into the heart, and are carried from there to the rest of the organism. Let me say here that all of these substances are of course now liquefied, some are more thickish fluids and others less so, and the thickish liquids do indeed enter the blood vessels and from there reach the rest of the body. However, gentlemen, think of what happens when you put sugar into a glass of water and drink it. Of course, the water isn't sweet only at the bottom, where the sugar settles, but all the water tastes sweet. Sugar dissolves in the water. The same is true for salt. This glass of water, which we might compare with the human body, does not need special vessels to distribute the sugar or salt everywhere, because they are absorbed everywhere by the liquid.

I told you some time ago that human beings consist of 90 per cent water, or at least liquids. We are talking of living water here, but water nonetheless. Now, do these transformed substances then really need blood vessels in order to be absorbed by the entire body? Does the sugar produced in our intestines need special vessels to reach all parts of our organism? No, of course not. We human beings consist of so much water for the very purpose of distributing the sugar everywhere.

People used to say that the alcohol a drinker consumes enters the heart by way of the intestines and from there is then distributed throughout the body. Let me assure you, gentlemen, if all this alcohol entered the heart first, the person would not die in a few years, but in a few days instead. In fact, it can be proved that any liquid food we take in doesn't reach the rest of the body by way of the blood vessels, but instead in the same way sugar added to a glass of water is distributed in all of the water.

True, when a healthy person is thirsty and drinks a glass of water, then this water is assimilated and added to the chyme in the intestines as needed and reaches the heart and the rest of the body by way of the blood vessels. However, once the blood vessels and the heart have received enough, no more water is distributed through the vessels, no matter how much we drink. No more water is needed there. If we drink just enough to quench our thirst—say one glass or one and a half—it doesn't do any harm at all. But anything beyond that amount, any excess—say, a third or fourth glass—will lead to excretion of the water in urine. This unnecessary liquid will not, as it were, bother to go through the heart, but since our organism is a column of water and this extra amount is superfluous, it is simply discharged with the urine. Just imagine what happens when people sit in a pub or a bar and have their third or fourth glass of beer. You can see them get up and walk away somewhere! This beer did not take the time to go through the heart first; it left by a shortcut, because, after all, the human organism is essentially liquid.

Thus, we can summarize as follows: the chyme, consisting of sugar, liquid protein, glycerine, fatty acids and minerals, is absorbed directly by the entire organism. Only the more thickish liquids are distributed by means of the blood vessels. That's why minerals can be deposited in our head and other organs; they get there not through the blood vessels, but enter the organs directly.

If we'd always feel the salt and minerals being deposited in our heads, we would suffer from headaches. An excess of salt in the head causes pain there. You've probably heard of migraine, which we've already discussed earlier. Things can be explained on different levels. What is migraine? It is brought about by excessive mineral deposits, particularly of uric acid, in the head. The uric acid is not excreted with the urine, but remains in the head. This is because food was not prepared properly and retained minerals. Migraine is not such a ‘refined’ illness, after all, even though it mainly afflicts ‘refined’ people. Migraine is actually a rather indecent illness. Substances that should have been excreted with the urine remain instead in the right part of the head because they were already beginning to deteriorate in the stomach. In other words, whatever works on the left side of the organism affects the right side of the head. I'll explain in a minute why this is so.

How much salt and mineral substances can our organism put up with? Remember, as I said earlier, our head contains brain fluid. It is only because of this brain fluid that our brain is light enough for our organism. As you know, a solid object has a certain heaviness or weight in air, but when we put it into water, its weight is reduced. If this were not so, we would not be able to swim. If the brain were not suspended in fluid, its weight would be about three pounds or 1500 grams. Suspension in brain fluid reduces the weight of the brain to a mere ounce or about 20 grams.

However, accumulating salt deposits increase the weight again and make the brain too heavy. True, being suspended in fluid decreases the weight of the brain as well as that of the salts deposited there. But now think of the differences between human beings and animals. You see, our head is put on top of the rest of the organism, which thus supports the brain. This is different in animals; there the head lacks this solid support and hangs, as it were, over the front of the body. What are the consequences of this difference? In human beings the slight pressure of the head is absorbed by the body. This pressure is not absorbed in this way in animals, and this is a major difference between humans and animals.

Scientists are always trying to figure out how humans evolved from animals. Well, it's OK to try to understand this, but, really, that's not the way to look at human beings. For example, we can't say that because monkeys have so and so many bones and human beings have the same number, they are basically alike. It doesn't change the fact that even in gorillas or orangutans the head hangs down over the front of the body, no matter how upright they walk. The human head, on the other hand, is supported by the upright body that absorbs the pressure.

Something very remarkable is going on in us there. The minerals we have in us move from the stomach to the head and are deposited there. If there's too much of them, they have to return through the body to be excreted. But something else must also happen to the other substances we have in us after digestion. While they move upwards, they undergo another transformation because the upright body partly offsets gravity. These substances in part become lighter, and in part they become more concentrated, condensed, and then form sediments. As we often find sediments when we try to dissolve something, so here there are sediments or deposits along the way as these substances move from the stomach to the head. Well, the smallest particles move upwards, and on the way they are transformed by the reduced gravity. What happens to them now? These substances originating in our food now turn into a kind of phosphorus. Indeed, the nutrient substances are not merely moving up into the head, but on the way some of the sugar, glycerine, and so forth is transformed into phosphorus.

You see, there are basically two kinds of substances in our head: salt and other minerals, which are still pretty much as they were before we ingested them with our food, and phosphorus, diffused like air, in fact in a dispersion even finer than that of air. These two, salts and phosphorus, are what we mainly find in our head. The others are present merely to keep us alive. But the two most important substances in the human head are salts and phosphorus. As I'll show you later, it is possible to prove that human beings cannot think properly if they don't get the salt and other minerals they need. We need salts and minerals for our thinking. Adding this point to what we have already said about thinking, you can see that human beings are very complicated.

salt and phosphorous in the head

If we have too much phosphorus in us, which is due to eating food that's too spicy, then we get fidgety like a spoiled child, wanting to touch and have everything. Phosphorus is responsible for our willing. If there's too much phosphorus, our will becomes fidgety. When this excessive phosphorus level reaches our head, we will not only be fidgety and nervous (which is due to the phosphorus, not to the nerves), but we will actually throw fits and go raving mad. In order to be able to have any will at all, we must have a small amount of phosphorus. But too much of it makes us insane.

Well, imagine someone gives you some salt, and you want to get it to think. How would you do that? But you are actually doing this very thing all the time. In our head we always use salt to think. Next, scrape a bit of fine, powdery phosphorus off the tip of a match and try to set it on fire. This substance is supposed to have will, to be full of willpower. Oh, it'll burn and evaporate all right, but it won't develop any will-power. Yet we are doing this very thing all the time inside our body.

Don't you see now that there's something in you that is more intelligent than your poor head, which cannot transform salt into a being of rational thought nor phosphorus into a being of will? This something in us is what we can call the soul-spirit, living and working in us. It uses the salt and minerals in the head for thinking and takes the phosphorus finely dispersed like smoke, for willing.

If we study things in the right way, we move from the physical to the soul-spiritual realm. But modern scientists don't look beyond the stomach. At most, they know that sugar and other substances develop in the stomach. Then they lose track of how substances are distributed in the body and ignore what happens beyond this point. This is why conventional science doesn't have anything to say about soul-spiritual matters. This limited science must be extended and supplemented. We must not restrict ourselves to the stomach and think of the head as merely tagged on at the top of the body. How salts and phosphorus get up into the head can't be seen. People therefore imagine that the same processes as in the stomach also take place in the head. This is because modern scientists usually know only something about the stomach; yet even there they merely realize that new substances are formed but do not know that the liver perceives and the kidneys think. They don't know this because, after all, they don't know very much about the head either.

That's why conventional science does not even look for anything else, thinking the liver on the autopsy table provides complete information. But the information to be gained from this liver is far from complete, because at the time when it was removed from the body the liver had already lost its soul forces. As long as soul forces are in the organs, the latter can't be removed from the body. There you can see that a truly serious science has to continue where our modern science stops. That's what's important. That's why we have built the Goetheanum here, to enable scientists to know not just something incomplete about the stomach, but instead to be able to explain the entire body. When they can do that, they will represent true science.