This is an outline of evolutionary intuitionism, hopefully written so that an intelligent teenager can understand it. It does not replace the book but gives a helpful overview. It also takes into account some points I made in the paper titled The Evolution of Moral Standing without Supervenience.

The Orphan

Imagine that you have found an orphaned child in the wilderness. You know that it is an orphan because its dead parents are nearby. If you do nothing, the child will die from hunger and exposure. You have three choices. One option is to leave the child to die of hunger and exposure. Another is to kill the child so that it suffers less. And, finally, you can take care of the orphan at least until you can get it into more capable hands.

If you are a normal human being, you know that you shouldn’t just let the child die and that you shouldn’t kill it to reduce its suffering. You know that you have to take care of the orphan. You have no other choice.

We have to explain why you think that. It is a fact that you believe it, but why?

And explaining it is important because you shouldn’t—in a different sense of the word—feel that way.

You should not feel that way because of evolution. Throughout most of human history, we did not have extra resources like food. As a result, raising an orphan would typically mean being unable to raise another child of your own. Since biological fitness is a combination of your own survival and how many children you have, you would have been less fit biologically than someone who ignored the orphan. But you know that the person who raised the orphan would be a better person than someone who refused to.

Your belief that you should care for the orphan cannot be a biological adaptation because it would make you less fit and adaptations make you fitter.

It cannot be non-biological in origin because natural selection would eliminate the lineages of people who believed such things. They would have had fewer children than more selfish people and selfish people would become a bigger and bigger proportion of the population until there were no more unselfish people left.

Some philosophers think that beliefs like the one we are talking about are logical truths. The trouble is that, although evolution could not make logical truths false, it could create people who could not believe them, and it would do so if believing them reduced our fitness. There are many people who cannot understand the logical truths of advanced mathematics and we would all end up like them when it comes to beliefs like the one we are talking about if they were logical truths.

There is only one option left, which is that our belief that we should care for orphans is the by-product of an adaptation and the by-product cannot be separated from the adaptation.

What is this about? Here is an example of a by-product of an adaptation that cannot be separated from the adaptation. Human newborns are helpless compared to kittens. They have big brains, which means bigger heads. But they cannot grow too big for their mothers’ bodies. So, they have to be born at an earlier stage of development, which means that they are comparatively helpless. Our big brains are the adaptation and our helplessness as babies is the by-product and obviously you can’t have one without the other.

The belief that we should care for orphans is a moral belief. The upshot of the discussion is that right and wrong, good and bad, must be explained as the by-product of an adaptation. Morality cannot be an adaptation or a product of culture or a branch of logic. Most of the work on morality that has been done by philosophers and others is not just the wrong answer, it is not even the right kind of answer.

From Companions to Community

Here is an answer that is at least the right kind.

Most animals do not plan for the future but human beings do. An adaptation arose by chance, as adaptations always do at the beginning. The adaptation was a belief that the believer was of value. This increased the probability that the believer would not just plan for the future but also carry out the plans successfully. After all, if something is valuable, you should protect and preserve it. If someone believed that they were of value, it made them more likely to protect and preserve themselves and carrying out plans for the future is one way to do that. Of course, all animals protect and preserve themselves but only human beings do so by planning for the future.

People can accomplish more by co-operating with others than by working alone. So, two people who believed that they were of value could do better by working together. But each of them had to be sure that the other was the right kind of person. The way they could tell was if the other treated both of them as being of value. The other would protect and preserve others as well as themselves. They would be trustworthy.

People could not just pretend that others are valuable. If they just pretended, they would stop co-operating if it was to their advantage and if they thought they could get away with it. They wouldn’t always get away with it. For best results, they had to really believe and they had to act as though they really believed.

People co-operated before they developed beliefs in their own value but the beliefs changed the quality of the co-operation.

The original companions had families and friends. They did not want their companions to treat them badly and, likewise, they did not want their companions to treat their relatives or friends badly either. So, the companions had to believe and act as though they believed that a wider range of people were of value. They negotiated this.

The others whom they accepted as being of value either actually possessed the symptoms of believing that they and others were or value, if they were adults, or potentially possessed the symptoms, if they were infants.

But this means that someone would be inconsistent if they did not accept all others who exhibited symptoms of being actually or potentially of value—even if they did not negotiate with them. Doctors would be inconsistent if they diagnosed two patients differently when they had the same symptoms even if they were ignorant of the cause of the disease. So, likewise, people would be inconsistent if they accepted some people who exhibited or would exhibit symptoms of believing that they were of value but rejected others who exhibited the same symptoms. The outcome is a community of believers and potential believers, which we can call the moral community.

Lots of philosophers think that consistency requires that there to be some other underlying characteristic that makes people valuable. What makes a tool valuable is that you can use it for something and if you cannot, because it has become too dull and cannot be sharpened, for instance, it is no longer of value. So, they spend lots of time looking for underlying characteristics. The search has been unsuccessful so far and there is no reason to think it will ever succeed. But the inconsistency here does not depend on hidden underlying characteristics but on obvious symptoms and we don’t have to join them in the search.

So, now we have an answer to the question of why we must care for the orphan. Yes, it is a cost and a burden but if we do not pay the cost or bear the burden, we lose the benefits of believing that we are of value and of being part of the moral community, and the benefits are generally greater than the costs.

How do we know that this answer is correct? The best we can do is to look for confirming evidence. The hypothesis, like other hypotheses, actually tells us what to look for. If morality is the by-product of an adaptation that makes us better at planning for the future and carrying out the plans, then anyone who does not care about others is going to be bad at planning. Psychopaths are the only human beings who do not care about other people. They are also bad at planning and carrying out plans, according to the researchers who study them.

Things Get Messy

Some things have rough edges and we sand them down. If the story so far were the whole story, there would be rough edges. People would have to give their lives to save a greater number of other people and that’s a cost that greatly outweighs the benefits of believing that you and others are valuable.

It is like too much electricity flowing through a wire, which can get too hot and cause a fire. One way to avoid disaster is to install breakers that cut off the flow of electricity if it threatens to overload a circuit.

So, there was selection moral breakers too. Our belief in our own value came to depend on our being able to desire to save ourselves from danger more than anything else. Saving others at the cost of your own life would be something you could not do while desiring to save yourself more than anything else. This makes it impossible to have a duty to die for other people. You may do it voluntarily, and thereby show yourself to be an especially caring person, but you don’t have to.

Similarly, our belief also came to depend on our being able to desire to save our family more than anything else, except to save ourselves, and on our being able to desire to save our friends more than anything else, except to save ourselves and our families. You can always save your family or friends instead of saving strangers.

Our belief in our own value is a product of individual selection, our preference for ourselves is also a product individual selection, our preference for family is the result of kin selection, and our preference for friends is a matter of the selective process called reciprocal altruism. Everybody is in the same situation, so these exceptions do not cause any conflicts between members of the community.

Of course, if you could save everyone, you should save everyone. And a right to prefer saving some instead of others when you can’t save everyone does not mean that you can use others to save yourself or your family or your friends. If you did that, you could not object to others using you, your family, or your friends, and that would be worse.

Some people want more than they are entitled to. One way they can try to get away with this is by rationalizing their actions—making up a story to make their selfishness seem justified. But the fact that people rationalize does not mean that they will get away with it—because other people will not accept their rationalizations but instead criticize and reject them.

This enables us to make another prediction. People who do wrong will rationalize their actions to make them seem right, or to make them seem like the sort of thing that everybody does. If you think about it, it is obvious that people do rationalize. A youngster who is being mean to a sibling will often declare that the sibling hit them first even though they didn’t.

Groups can rationalize together. They can get an advantage over outsiders by treating them badly and rationalizing their actions by declaring that the outsiders are not really members of the moral community.

Furthermore, sometimes groups just share false beliefs or share an ignorance of the truth. If they have false beliefs about what is harmful or helpful, they can end up doing the wrong thing and thinking they are doing the right thing. For example, there is plenty of evidence that vaccines are safe and effective, but there are people who mistakenly believe that they are harmful, who discourage others from getting them, and who thereby harm the others. It is wrong even though the anti-vaxxers think it is right. Philosophers would say that the anti-vaxxers are objectively wrong but subjectively right.

Since our beliefs in our own value and the value of others are not the only beliefs in the mix that influence the outcomes, we can expect there to be differences of opinion on moral issues between individuals and between groups. In fact, the world will look as though relativism were true. This is another confirmed prediction of the theory.

Here’s one way to think about the variety we observe. Our beliefs in our own value and the value of others is the genotype of morality. It is the same everywhere. Our ignorance, our errors, and our rationalizations are the environment. The phenotype of moral codes depends not only on the genotype but on the environment as well. Cuttings from the same plant will appear quite different depending on the conditions in which they are grown. It is the same with morality.

What Do We Have to Do?

If we can do so safely, we should minimize loss of human life and injuries to human beings.

We should treat everyone equally, which means we can never use other people or regard ourselves as more important than anyone else.

And, we should try to acquire relevant true beliefs and to avoid relevant false beliefs, so that we do not do the wrong thing because we mistakenly think it is the right thing.

Of course, what is simple in theory can become complicated in practice.

We may have to not just co-operate with others but to create complex institutions. We may have to build hospitals and medical schools and health systems to minimize loss of human life, legal systems to ensure than nobody is cheated or exploited, and schools and universities and research facilities to seek out truths and eliminate falsehoods.

One difficult problem is how to view abortion. The question is whether we have to see fetuses as potential members of the moral community or not. They will definitely grow into potential and later actual members but that doesn’t answer the question. On the one hand, it appears that potential members should include infants but not fetuses. Fetuses are still inside their mothers’ bodies and it is enough to protect the mothers. On the other, if they originate at conception, abortion is wrong except to save the life or health of the mothers—because mothers do not have an obligation to sacrifice themselves. I used to think the latter way but now I think the former view is better. It is just hard to imagine that people would negotiate an agreement that included fetuses as members of the community, because, throughout most of human history, there was no way to help or harm them without helping or harming their mothers. Once they are born, however, the situation changes radically. But I must admit that I am not completely certain about this.

What Motivates Us?

Philosophers want to know why people act morally.

In a pinball machine, the trajectory of the balls is determined by the flippers, which impart energy to the balls, and by the bumpers, which the balls bounce off. If the ball is going in one direction, hitting a bumper changes its trajectory.

Our desires are like the flippers and our beliefs, including our belief in our own value and the value of others, are like the bumpers. We do not have any particular desire to act morally, and we often have motives to do wrong, but our belief in our own value and the value of others helps determine our trajectory.

Technically, we have a disposition not to act inconsistently with our belief in our own value, if we act at all. Some people might think that this is just a disposition because they think the negations cancel each other. But that does not happen when we say that it is not necessarily not true that P even though there are two negatives there as well. What we can actually infer by eliminating the negations is “possibly P,” not “necessarily P.” It is the same here.

So, we are not really motivated to act morally. Instead, given our belief in our own value we are bound to act morally if we act at all -- unless we lack relevant true beliefs or possess relevant false beliefs, of course.

Dealing with Philosophers

Philosophers have discovered things that we have to take into account.

David Hume pointed out that it is impossible to derive prescriptions (ought-claims) from descriptions (is-claims) using logic. He was right. But the point is irrelevant here because our belief in our own value is not something that we have to prove to be true. All we have to do is to show that it has been naturally selected. Natural selection is not logic. I would add that, because Hume was right, if morality does not have a naturally selected belief (whose content is evaluative) as its foundation, there is no foundation that morality could have in a world like ours.

J. L. Mackie claimed that moral facts would be weird. But the moral facts here are just a combination of our beliefs in our value and true descriptions of acts. Logicians do not think it is weird that a set of statements is consistent or inconsistent, even when some of the statements are false, and moral facts are like beliefs about consistency or inconsistency.

We have moral intuitions like our belief that we should care for orphans. We subconsciously detect the inconsistency between our belief in our own value and failing to care for orphans. It is like some grammatical intuitions. One reason we use the passive voice instead of the active voice is to put information at the end of our sentences when we believe our listeners don’t know it yet. But most people, including most English teachers, don’t know that that is the reason. It is subconscious and they know what is right but cannot explain it. It is the same with our moral intuitions.

Jeremy Bentham claimed that, if we relied on intuitions, we would just be pontificating pointlessly. He ignored the point made by Sir William Blackstone that our intuitions can be contaminated by ignorance and error. He also ignored the fact that his own theory had the same problem and had to solve it in the same way. Disagreements over intuitions are a problem only when the people who disagree believe all the same things otherwise. Incidentally, this gives us another way to test the theory.

Philosophers like Peter Singer who discuss the trolley problems think humans are inconsistent because, on surveys, most of us say that we should turn a runaway train so that it kills one worker instead of five workers but that we should not throw a bystander in front of the train even to save five. But if we ought to throw the bystander, we ought to jump ourselves, or throw our children instead of the bystander. This conflicts with our biological nature. And, if we do throw the bystander, then we are saying to everyone else that they can do the same to us or our children. We definitely don’t want that. In sum, throwing someone else in front of the train conflicts with our biological nature but reducing the total casualties by re-directing the trolley does not.

Our belief in our own value is switched off unless we are simultaneously able to desire to survive more than anything else. So, if we do desire something more than that, our belief is switched off. But, if someone’s belief is switched off, it is no longer wrong to kill them. Although this is true, people’s beliefs are seldom switched off and even less often are others aware that they are switched off. The philosophers who think that this is a problem think about the totality of moral truths as though it were a universal generalization, which can be shown to be false by a single counter-example. But we are not dealing with a universal generalization but with a testable evolutionary hypothesis. Evolution does not produce logical perfection. Instead, it just produces something that is good enough often enough that it gives us a better chance than our competitors to survive and reproduce. It is silly to complain that the result is imperfect.

The idea of a belief that can be switched off is strange to philosophers who think that truth matters more than anything. But we don’t believe we are valuable because it is true but because it increases our fitness. In fact, if it were true, we would have to throw ourselves in front of the trolley to save others, as long as we saved more than one. True beliefs are generally desirable but not in this case.

Lots of philosophers now say it is wrong to eat animals. The reason they do is that they believe that moral standing is a function of other characteristics and that we share the other characteristics with animals. But, as pointed out earlier, we negotiate moral standing with one another and our logical commitments depend on symptoms, not underlying characteristics. As a matter of fact, only human beings have become members of the moral community through negotiations. However, it is conceivable that there could be negotiations with members of other species. There just happen to be no other species with which we can negotiate.

Furthermore, if the animal rights philosophers were right, during most of human history, righteous individuals would have had fewer resources (because they could not eat animals) and less territory (because they could not use animal skins to make clothes for cold climates). Consequently, the righteous would have been replaced by less scrupulous people and we would not be moral at all now. Since we still care about right and wrong, and good and bad, animal rights philosophers must be mistaken. It does not follow that it is all right to be cruel rather than kind to animals with which we develop relationships voluntarily. So, it is perfectly fine to love and protect some animals while using others for food or clothing after treating them humanely throughout their lives.

The Upshot

So, what does it all mean?

It means that there is at least one theory that is in the right area.

It means that ethics is a subfield of biology, which makes ethics scientific.

It means that morality can exist in a purely physical world among purely physical organisms.

It means that our differences of opinion do not mean that there is no morality.

It means that there is such a thing as right and wrong, good and bad.

It means that the most practical thing we can do to become better people is to do our best to eliminate ignorance and error by trying to ensure that we believe things only when we have enough evidence for them. Our belief in our own value is the only exception. It is an exception because it has been naturally selected and not acquired like other beliefs.

It means we should try to avoid rationalizing even though it makes us feel better about ourselves.

It means that there is a sense in which we really are each other’s sisters and brothers.

It means that this answer to why we should care about orphans is good enough until someone comes along with something better.