You can tall me "teach." Better yet, call me "Think." Teachers usually teach things that are well developed, widely believed and backed by a well-developed literature and teaching aids and traditions. I have none of these. But I do have the truth, so listen.

I am trained as a doctor and as a scientist. See. Here are my Harvard Medical School diploma and my passport. If they are forgeries, then I am a felon and it wouldn't take you long to prove it. I am telling you this because we are about to discuss something very important, one of the most important things you will ever learn. I will tell you in about two minutes, and then I will back it up.

All right, I am a doctor and a scientist. I'll write it down in doctor speech for you. You can see why nobody can read a doctor's handwriting but himself. Doctors disagree with each other. They disagree with other people. You may disagree with me. But it is very important that you understand me. Knowing my training may help.

Second, evolution happens. It happens to people and it is going on right now. We will come back to this, but it is inescapably true.

Third, evolution has already affected people to that point that visible changes have occurred; people are different because of evolution

Fourth, people have low fertility. A healthy dog may have ten puppies in a litter. A human woman on average cannot have that many children in a lifetime.

Fifth, cross breeding lowers fertility. This is well established and widely known.

Sixth, sufficient cross breeding among humans will result in extinction. This is proven from points four and five.

Seventh, and this is a matter of judgement, but I hope we agree, extinction of the humans is something to avoid. If anything in life, anything in the world, is important, this is important.

Now this is not a call to go around being rude to people or thinking the less of them because of their choice of mate or the happenstance of their parents. There are four reasons. One: If you talk about this, you can expect people to be rude to you. Two: People's record in helping each other select mates is extraordinarily poor. Three: A cooperative social order is as vital as life itself; we must not destroy it. Four: Well, we are talking about things that change with time and must remain humble.

BUT, humble or not you must act in the world. Armed with the truth, you may make a less disastrous choice of mate yourself. At least you need to understand. This is important.

Let us go back to the first point and see where we stand.

The first question must be: "Is anything important?" "Does anything matter?" "Who cares, anyway?" Some things need to be true before we can say that anything is important: There has to be a universe, a reality; something must exist. If our lives are a chaotic swirl of impressions without connection or implication, then life is as Shakespeare suggested, "A tale told by an idiot, full of sound and fury, signifying nothing." Well, I don't think so. And I don't see how, if you woke up today and are listening to me and follow what I am saying that you can think so. So we will take as given that there is a universe. In some form or other something is TRUE.

Second, for anything to be important, we must be able to get AT that truth. We may never know it for a certainty, or we may. But if we can never approach the truth at all, then we are mocked. The universe is our tormentor. Life, existence, may be important somewhere to something, but not to us. It doesn't matter to us if we can never have a clue about what is "really" happening, if our opinions and choices are totally without relationship to that reality. So I take it as given that we can at least in part know this true thing, this world and universe in which we are groping around.

Now let us make a distinction between two kinds of truth: There is truth that changes with time and there is truth that is fixed without regard to time. I hope some day we can come back and talk about time. There is much to say about it. For now, just accept it as what you ordinarily call time. Some things change with time, and some do not.

Things that do not change include mathematics: Given the assumptions stated by an ancient man named Euclid, if two straight lines are perpendicular to the same line, they are parallel to each other. Also, the angles of a triangle add up to 180 degrees. Also if the angles of a triangle are all equal, the sides will be equal as well. These things are true all the time. You can change the assumptions than underpin them, but given the assumptions, you are given the results: these things are true without respect to time.

Similarly, either there is an eternal God, or there is not. This is not going to change, despite what philosophers and theologians tell each other. The arguments change, but God, in His existence or non-existence transcends all such considerations.

Then there is the kind of truth that changes with time. I am standing here right now. By the time you see this, that will have changed. You can cross an intersection if the light is green. Moments later, the light will change and you no longer have the privilege of crossing. Your freedom has been curtailed. Moments later, you will have it back again.

I am trained as a doctor and a scientist. I will confine myself to the kinds of things this training addresses. It is not that I have no opinion on things of permanent truth; it is just that these discussions will be limited, so far as possible, to the kinds of things that change.

We know we can know permanent things. We must also be able to understand things that change. We may never understand completely, but we must be able to approach truth, must be able to make ourselves less ignorant by looking and asking; otherwise we are mocked just a surely as if there were no universe. And we must be able to act on that knowledge. So, I take it that there is a universe that changes with time, in which we can know things and can act on our knowledge. It only remains that we care. Then things matter; things are important. Do you care? About anything? If so, we can proceed. If not, then all I can say is, "I care, so do what I tell you. You have no reason not to. You don't care anyway. So you can't care enough to defy me, so follow these instructions: know and care."

So now we all ought to be together. Things matter because there are, along with permanent truths, a universe in which we can learn and act and care about; and this universe changes with time.

What matters more? Things matter; what is most important? The obvious way to sort them out is by how long it took to get them.

Permanent truths are clearly the most important, but we cannot change them.

The existence of a universe is next most important. We cannot change that although some day again I would like to discuss the matter.

Our environment in that universe is the next most important thing, the thing that matters most. Surprise; we are already faced with choices, with making policy, with making changes. It took, according to our present scientific knowledge, billions of years for the universe to reach a stage where the earth was ready to support our sort of human life. Given an environment, it seems quite likely that after a few billion years we might get people again. I will not go so far as to say probable; there is just too little information given what seems to be a unique event. But no environment, no people. I will stand flat-footed on that position.

So of all the decisions we will ever make, the suitability of the environment is the single most important thing. Personally, I like a lot of trees and wild things, and I like a lot of books and houses. Your choice of how we shape the environment may be different. But that environment is more important that we have; it has demonstrated that it can make us. We have never demonstrated we can make it.

Given an environment of living things, the next most important thing is an impulse to help each other, to cooperate. Many animals seem to have this. Perhaps it is not vital to intelligent life, but I think it is vital. Some sort of social order must be there. At least it seems to have been there early on, before we had what we can call people. And by people, I mean creatures that can understand and care about their lives; who can care. They might not be human.

Given a suitable environment, the next most important thing is the genetic makeup of humans in the broadest sense. Sorry, we just cannot exist as humans without the genes to do it with. The integrity, the viability a gene arrangement that would support humans was a long time in coming. It took hundreds of millions of years. It is the third greatest treasure we possess after our environment and our impulse to help one another.

There was a creature scientists call Homo erectus. This was not a human. This was a different species, a species that used tools but had a skeleton that just was not what we have. Recently tools used by the Homo erectus creature have been discovered on islands in the Pacific that could have been reached only be crossing twenty miles of open ocean. The current interpretation is that Homo erectus had the technology build to seaworthy craft. It occurs to me that there are people alive today who have swum such distances. But it doesn't matter; Homo erectus cared. I am as impressed by a twenty mile swim as I am by the knocking together of a little raft.

The tools dropped by Homo erectus are nine hundred thousand years old. I would call them people. Search no more for signals from outer space to tell us we are not alone as humans, as intelligent life. Intelligent non-humans were here hardly more than a heartbeat ago. Gone now, but they lived. And they were cooperative. You have to trust somebody a lot before you teach him how to make a stone axe.

So what are we that the Homo erectus was not?

I think our languages must be better. I should call them our next most treasured possession. Then there is our technology; that was a long time in coming. Then come our art, our religions and our fund of knowledge. Then I suppose there would come our great institutions, our nations, courts, universities and businesses. Finally would come our capital accumulation, our medicines and our luxuries.

You may wish to change the order of these things a little. But the critical issue here is genetic makeup; it is right up there with social order just below environment. All other matters are of lesser concern. Sorry. This really matters. So as a doctor and a scientist I am talking about your genes, your gene pool. The one thing that after your environment and social order makes your life possible - makes it possible for you to know and care.

The second point you must understand is that evolution happens. Evolution has been going on a long, long time. Perhaps your religion conflicts with this statement. Remember I am talking about things that change with time and the way things that change look to us. Many people look for a divine moment of creation. I have no problem with that; I am not talking about creation. I am talking about right now.

Here is what evolution is: Evolution is the process by which inheritable variation causes differences in survival and differences in survival cause changes in inheritable variation. It is as simple as that.

The details of genetics are well worked out and are becoming more so daily. In fact, this is the scientific revolution of the present generation. But fascinating and important as the details are, they are not really important. Darwin worked out his theory of evolution with only a very hazy knowledge of genetics. A man named Gregor Mendel (1822-1884) had made revolutionary advances in the understanding of genetics during the lifetime of Charles Darwin (1809-1882). Neither Darwin nor anyone else took much notice until the end of that century. Yet Darwin formulated a theory that bears his name, despite some modifications, to this day.

Think about it. There is inheritable variation. Children resemble, within limits, their parents. The children, when they reproduce, pass on the same characteristics more or less to the grandchildren. How many grand children there are depends on a number of things. It may depend of choices that are made. It may depend on accidents. And it may depend on the variation that is inherited. When inherited variation affects the number of grandchildren, at it usually will, the average genetic makeup of the grandchildren is different from that of the original parents. That is evolution.

Suppose we are looking at a group of small animals. Some have longer hair, some shorter. It is a genetic variation. The climate gets colder. Animals start to freeze. The longhaired ones freeze less. In time, the average animal has longer hair. That is evolution. Any time a farmer selects an animal to breed because it suits his purposes better, and the result is offspring that continue to suite him, evolution has occurred.

We generally refer to "natural" selection as the driving force in evolution. As if
"nature" were making choices and as people we somehow stand outside of "nature." Sorry, as a doctor and scientist I do not see that. We are as much a part of nature as anything else. Our rational and deliberate selection is still a "natural" selection, since we are not supernatural beings. Breeding is just evolution. It happens.

When the genetic makeup of a population changes BECAUSE of the effect of inheritable variation, it is evolution. Other things can cause changes. Suppose some madman unleashed a nuclear weapon in some part of the world. Chances are that the people there would be, on average, genetically different from people elsewhere in the world. This would constitute genetic change by choice, but it would not be evolution. Suppose an asteroid struck the same area. The same genetic change would occur, this time by accident. But since it was not CAUSED by genetic variation, it would not be evolution.

Well, people have genetic variation. You know that. I know that. And that genetic variation changes people's chances of having children. You know that. I know that. Some people die young. Some are physically more attractive. Some have mental and emotional resources that give them an advantage, and some of that is genetic. Therefore, absolutely and inescapably, evolution is happening to people right now. Evolution is not something that happened in the past, made us people, and then went away.

Knowing that evolution is happening to people right now, and has been happening as long as there have been people, the question arises, How much? Putting a number on evolution is difficult, and at first blush it would seem that the way to do it is this: know in detail the exact mechanism of genetics and the makeup of the genetics of humans. Then establish exactly how much change occurred to some group of people over a period of time. The trouble with such a number is that it would not have any emotional reality. It would mean nothing to us.

I suppose it might be possible to establish some breeds of dog as benchmarks. Then one could compare the differences between groups of people, or the progress of one group, with the difference between a couple of breeds. This would still lack impact. It would be impossible to put a human value on it.

There is another approach. Instead of measuring evolution by its result, measure it by its cost. It is a lot easier to get a feel for difference in value between glass and diamond by asking prices than by studying their sub-microscopic structure.

And evolution is costly. It is very costly. It is paid for in dead babies, in disappointed adults, in pain and deprivation. And deaths and disappointment are easy to count.

I went to a public school. We had about thirty in each class. Let us say that for each class, there was a child who was missing because of an unsuccessful pregnancy, and that failed pregnancy had a genetic cause. There was probably more than one. Let us suppose that for each class there was a child who had died in infancy or was so challenged by genetic factors mental and physical that he could not cope with the demands of the class. There was probably more than one, fortunately fewer nowadays than then, but still probably more than one. And let us say that in the class there was a person who was for genetic reasons just not very attractive to possible mates. So for thirty children who could chose whether they would have children, there were three who could not because of genetic factors beyond their control.

The elimination of those three or more changed the genetic makeup of the next generation. That was evolution. And for humans I think a reasonable minimal cost of evolution is ten percent of the population in any generation. In fact, I believe the cost is much higher, but let use say ten percent. That is very expensive.

There are, of course, other things as work on the gene pool. Choices and accidents have been mentioned. Also, there is in a gene pool a constant supply of new, mostly defective, genes arising by the process of mutation. To a first approximation, their elimination from the gene pool by death or the inability to reproduce is not strictly evolution. It does not produce change, but only maintains the status quo. It is a cost we incur simply because we are creatures that depend upon genes.

Next, compare our rate of evolution with what you might expect to happen to other animals. It appears to those who look at such things that we, all living things, are descended from a form of blue-green algae. Well, I have not spent much time with blue-green algae myself, and would be the last to sneer at another living thing. But forgive me for having the opinion that blue-green algae don't make many choices.

The reproductive opportunities of blue-green algae depend a lot on chance, on accident. Humans have, and for thousands of years have had, a society that reduces the degree of chance in our lives. Whether we reproduce has a lot more to do with how we are accepted, on our social value as individuals, than on which way the wind has been blowing or the tides running for the last week; with algae the exact reverse is the case.

So we would expect that genetic factors would be much more important to humans and thus evolution proceed far faster that it would with algae, or with any other wild living thing. Breeds of domestic animals, since they may be selected by humans, may evolve with great speed.

For another thing, when I hold a glob of algae in my hand, I can't think of a lot of ways in which I would improve it right away. Give me the chance to make enough changes, and I will show you a redwood tree and a whistling marmot and a Gerbil and a virus and so forth. But what should be the first step? Have some of the algae break up into single cells? The cost of those divisions might be so great that they might die out. Give the mats of algae little tails, so they can swim into different areas? Again, it would cost metabolic energy and probably be as likely to push them into bad areas as good.

But humans, ah. Now I have a host of things I would like. First let us have back the ability to regenerate lost limbs. Next let us have a permanent supply of the stem cells that let us reject early cancers. Next, please do something about that wretched upper airway that has us choke on our food so much. And blood vessel, give us longer lasting ones. Give us replaceable ones, and renewable teeth. I could go on and on.

In other words, as well has being spared most of the accidents other living things face, we have a host of directions in which we could obviously and profitably move. Evolution in humans is terribly costly but makes more progress, and has been making more progress, with humans than with most living thing.

Our third point is that people have already undergone evolution to the extent that there are obvious differences between groups of people. Surely this point is so obvious it need not be belabored. American Indians have high cheekbones. Some groups of Asians have an epicanthal fold around the eye. Bantu are taller than pygmies are. European men go bald. Of course all these differences are trivial. The important thing is that there are differences.

The fourth point is that people have a low rate of reproduction. We are not "fecund" as say mice are. Someone has studied primitive tribes and decided that the maximum number of children that the average woman can bear is about eight. New England puritans exceeded that number for many generations, but theirs was an exceptional circumstance with the climate, the technology and the culture all working together in a way that will not happen often. Since women become fertile in their teens and remain so generally into their thirties and beyond, we might expect families of over twenty children to be common. It rarely happens. We simply cannot reproduce that fast.

The fifth point, and this is one that you must clutch to your heart because it is so seldom mentioned is: cross breeding reduces fertility.

The word mule dates back at least to the year 1000. It is the offspring of a male donkey and a female horse. It combines the strength of a horse with the endurance and surefootedness of a donkey. The mule's wonderful qualities mean it has been bred for a thousand years. And for a thousand years, people have known: the mule does not reproduce. It is sterile.

This is the typical pattern of cross breeding: an excellent first generation is followed by a reduced or nonexistent second generation.

Of course, if you try to cross breed two animals or plants that are too dissimilar, you will get no offspring in the first generation. Turtles and fish have shared ponds longer than humans have been around, but I have never heard of a turtle-fish hybrid and never expect to. True, science has put lightning bug genes into a tobacco plant and the tobacco plant lights up. But a plant and an insect do not breed with each other.

It is not all or nothing. There is no sharp limit of what you can and cannot breed.

The timber wolf and the gray wolf cannot be crossbred. Yet there is an animal, the red wolf, that has timber wolf genes and gray wolf genes and no other genes. In other words, the red wolf is a cross between the timber wolf and the gray wolf and they cannot cross breed … now. They could once. Once they were the same animals. Then they got separated. They continued to evolve, but since they were separated they evolved in different directions. A new opportunity, some new territory opened up. Both gray wolves and timber wolves entered it. They mixed and became the red wolf. Meanwhile the original gray and timber wolves, separated once more, continued to evolve in different directions and now can not interbreed at all.

There is a kind of bird called a flycatcher that is distributed all the way across Europe and Asia. In the west of the range it is called the pied flycatcher. In the east it is the collared flycatcher. If a pied flycatcher mates with a collared flycatcher, they will have a normal clutch of eggs, crossbreed birds. If the crossbreeds mate with either the pied flycatcher or the collared or other crossbreeds, the clutch of eggs will look normal at first, but instead of ninety percent hatching, only about thirty percent will hatch.

It is well known that you can plant a field with grain that is the crossbreed of two kinds of wild grain, and the field will give you more grain than either of the wild strains would. The principle can be carried farther. Take four strains of grain A, B, C, and D. Cross A with B and get AB. The harvest, as we said, will be good. At the same time cross C with D to get CD, again with a good harvest. Now next year you can cross your cheap-because-plentiful AB seeds with your cheap-because-plentiful CD seeds and get ABCD seeds, which will produce a wonderful harvest from cheap seeds. This is call "dihybrid" seed. Without the technique, the world could not produce half the food it does now.

In other words, most of the people alive to day would starve to death if it were not for crossbreeding grains. So cross breeding is good? Right? Isn't life better than death? Of course, but look again.

If you cross ABCD with ABCD you get a very poor harvest. You get a much poorer harvest then you would with A or B or C or D.

It is true that cross breeding feeds the earth. It is also true that you MUST have pure wild strains in order to be able to do your cross breeding. People have sacrificed their lives to keep those pure wild strains alive. Without those sacrifices, most of us would be dead.

You may have heard something like, "Cross breeding strengthens the gene pool." Not true. It may give you a generation of exceptional individuals, but that is followed by reduced fertility.

Of course it does. Think how many things blue-green algae turned into despite its rather unpromising appearance. Think how many things people could become. We are becoming those things. We are going off in as many different directions as be have communities. We are getting more different in more different ways than anything ever has before. But that is true only so long as we breed true. If we cross breed, then like any other living thing, we will have a first generation and it may be exceptional.

It is all around you. American children are bigger, smarter, stronger, healthier and more sociable than perhaps any society that ever lived. That is exactly what you would expect from a first generation of cross breeding. You would also expect it of dihybrids, and certainly we have many of those. Many are truly astonishingly wonderful human beings.

But ultimately, already, we have reduced fertility.

The sixth point it that sufficient cross breeding will kill us all. This is no longer a matter of looking at mules and grains and deciding that people probably follow the same rules. It has been tried.

There is a country in Central America where indigenous American Indians lived and where Europeans settled and then brought in Africans. The people in that country can be divided into groups. The Indians are all gone. There are groups of Europeans and groups of Africans. There are mulattos, who are a cross between European and African. There are mestisos, who are a cross between European and Indian. And then there are Zabo, who are Indian-African. Is anything missing? The pure blooded Indians are. But what about the three-way mix? My source said nothing of them. I doubt they are there. I suspect that the populations have been able, at least for a time, to survive their first crossbreeding. But the double-cross was so unsuccessful that they never even got around to making up a name for the offspring.

Sub-Saharan Africa tells the same story. It seems that until a few centuries ago the land was populated by Pygmy hunter-gatherers. Bantu developed agriculture and their numbers increased as they spread out of the Congo region. Of course agriculture is a lot of hard work, but it does let people live in much higher densities than hunting. Where a high-density local population meets a low-density local population and they interbreed, the outcome is predictable: the crossbreeds die. The high-density population can absorb the loss better than the low-density population, and the land becomes populated only by the high-density people. Thus an agricultural population will steadily expand into a hunting population as long as interbreeding continues.

And so it was. The Bantu spread and now dominate that part of Africa. Not all the Pygmies vanished. There is any number of tiny areas that are Pygmy with no Bantu at all. These areas have not interbred. At the very south extreme of the Bantu expansion there are, indeed, areas where they have interbred. The people in those areas are doomed. We know that, because we can look at the map as a time line. Where the Bantu have long been, there are no crossbreeds. Where they have recently arrived there are crossbreeds. Crossbreeds do not develop over time; they die out over time.

The process has recently been demonstrated in Britain. Using mitochondrial DNA analysis, which follows only female inheritance, scientists have looked at the bones of people who have migrated into the British Isles. The pre-Celtic Britons once lived there in vast numbers. A casual inspection of the English countryside will show terraced hills. Big fields have subtle changes in the color of their vegetation that look like a patchwork quilt. Obviously all of Britain was under intensive cultivation, far more so that now. It is and was a fertile land. They raised more food; they must have been feeding more people. They built vast monuments, including ominously an area around Avebury where there are a number of monuments, each of which resembles monuments from a different area. In other words, from time to time they gathered peaceably from all over Britain. Everyone had a monument like the ones at home.

Then the population crashed. You see, not everyone in Britain was alike. The DNA analysis shows six entirely different groups living there by the time Avebury was built. They had lived there since the English Channel cut them off from the continent thousands of years before. They lived in peace, and at Avebury for the first time they physically got together to cooperate and make friends. They crossbred. They almost died out.

They did not die out altogether, because modern DNA analysis identifies their descendants. At least a few hundred survived when their numbers were lowest. That is because among humans it takes more than a hundred people in a breeding group or the group will die out because of inbreeding. Yes, excessive inbreeding will kill off a population just as surely as cross breeding. I doubt more than a very few thousand survived, because they must at some time have reached a sort of equilibrium so their numbers could recover, and it is hard to reach equilibrium with a large number of people.

So a population of perhaps a hundred million fell to a population of perhaps under a thousand. Imagine the loss. Imagine the human despair, the loss of cultural treasures, the loss of so much of what makes us human. But this was England, one of the most fertile, safest, most hospitable places on earth. They had a long history of successful cooperation, and for a long time they were free of any outside pressure. They survived.

By the time the Celts arrived in about five hundred BC, the land was still just about empty. The Celts overran Britain, then the Romans, then the Anglo Saxons. There were Viking raids and at last the land was conquered by Normans. And today they have gone back and looked at the DNA. It is ninety-nine percent pre-Celtic. All those other invaders arrived only to interbreed and die out.

What else killed them? Disease and starvation would have struck everyone. They certainly weren't killed in battle; they won the battles. But when they interbred, their relatively lower numbers at any one time killed them off.

Now this is the story as told by mitochondrial DNA, and it is only half the story. Soon they will have analyzed the Y chromosome, the male chromosome, and that will be the other half of the story. The story may well seem different. Invading armies were doubtless more males than female. Yet with the story half in, the score is natives 99, conquerors 1. The score is breed with your own 99, melting pot 1.

These are things that happened when a few genetic groups got together. A young person at the time of Avebury might have to walk for days to meet at most a half dozen different groups. Compare that with what you can find in a few minutes drive in a modern city.

And it is already happening. Most prosperous countries are failing to reproduce themselves. Their young people are able to travel, select from a wider base and are less likely to have large families. Extinction is already on the horizon. It is not a possibility; it is happening.

Extinction is a terrible thing. Nothing else alive knows and cares as much as people. Our ability to learn is enormous compared with others. And as for caring, why we are loving-machines. We have discarded our body hair so we can be more intimate. The whites of our eyes are unique in that they are optimized to reveal rather than conceal the direction of our gaze and thus our thoughts. Lips! Nothing else has lips. Lips are the silliest thing, vulnerable and soft as they are. But they let us be affectionate.

The normal female breast varies enormously. The largest are so large that if they were all gland tissue, they would make enough milk to keep a number of adults alive. They fairly shriek, "Behold. I nurture." And male organs are comparable. If you are a normal human male, you need not feel intimidated by a gorilla. He has muscle, to be sure, but his sexual endowments are about on a level with his intellectual endowments. He just cannot compete with you.

Humans are designed to love, to care, to be intimate, to form strong bonds. This is as true as that humans are intelligent, determined and resourceful. If you care about anything, you must care about humans.

And now just suppose someone killed your child. I do not mean by accident or necessity. I mean your child was killed for sport, because it was fun to do so. Your feelings would be intense. Consider, within recent years otherwise sane and sociable adults have killed because of the issue of abortion. Whatever your opinions on abortion, the worst you can say is that a person who has one has, in effect, killed their own child.

But when a person mates with a person who is very different from themselves, and when the offspring of those people will live in the community that your children will live in, then the chances are very great that some day your children will mate with theirs. Since cross breeding reduces fertility, in effect they have killed your child or grandchild.

The pressure on you is excruciating, because you must under no circumstances try to prevent them. You can advise, but you must be willing to accept, death of your child and all. That is because our social cooperation is so important.

People have tried to control each other's mating. One example is Alexander the great. He tried to breed a super race by having his Greek troops take Persian wives. There are many Greeks alive now and many Persians. But of Alexander's super race, nothing remains.

Hitler took the tack of slaughtering whole segments of the population. This, alas, is what often happens when the social order is lost, when we fail to cooperate. He claimed to be doing it in the name of genetic purity, but of course that is almost as stupid as evil; if there is anything wrong with genetic impurity, it is that it is unable to survive even with assistance. I have known survivors of German death camps. Do not tell me it did not happen.

integration in the schools. The American public school system, the best in the world at the time, was ruined in the name of social integration. Make no mistake; everyone knew that this was in order to increase social interaction between different groups and that would lead to increased intermarriage. As with Alexander, this was mass murder. Sorry. That's what it was and is.

Do you see the pattern? Choice of mate is just too important to entrust to any government. There can be no laws about these things because if there are, there will be bad laws. Governments force people. People can only survive by cooperating.

I do not think people wish to harm their children or to harm each other's children. I think the truth will be enough. We have known for a thousand years that crossbreeding horses and donkeys reduces fertility. It is time we acknowledge that humans are affected by the same laws.

We must acknowledge it before it is too late. Time may be short.

Already we are not the same species but many species. We must confine our choice of mate to those who are close to us but not too close. We should not share ancestors any more recent that eight or ten generations. Beyond that, we should seek our closest kin. A breeding community should be no more than a few thousand, ideally a few hundred. There should literally be millions of different kindreds in the world, with no one taking a mate outside his own.

If we do that, we will have millions of species of human, all fundamentally different, each evolving in a different direction. Imagine the richness of such a future. Image what we will know. Imagine what we will create.

But if we fail, if we poison all our gene pools, extinction beckons. Only rotting ruins in a savaged land will mark our passage.