Monday, February 20, 2012

Darwinian Family Values: From Selfish Genes to Altruism

It's a Saturday night in south Louisiana; the weekend before Mardi Gras.  There's going to be parading and debauchery from now through Fat Tuesday, and I intend to see some of it.  But tonight, the rain is pounding against my windows, and I just can't get that excited about going out in it.  So, I'll risk the wrath of Bacchus by staying in and continuing my recent ramblings about ethics.

In my last two posts, I've been considering whether ethical laws are an intrinsic part of nature.  I've concluded there are good reasons to be skeptical about the idea of natural law--the idea that there are clear ethical rules implicit in nature, and that we can use our reason to discover them.  If the natural world evolved through a combination of  basic physical processes and natural selection, then there's good reason to question the natural law idea that everything in nature has a purpose, and that learning our purpose can tell us what is good.  If humans are chance products of natural selection, then we may have no purpose at all.  It seems quite likely to me that we weren't put on earth for any reason.  We are here because we happened to evolve.  I don't mean to wring my hands and say life is meaningless.  I think human life can be incredibly meaningful.  We are smart, curious, social, and talkative creatures living in a world full of wonders.  There are plenty of ways to find rewards and meaning in life.  I just don't think we can assume that we are here to serve some cosmic purpose.

Another reason to be skeptical about natural law is the problem of the appeal to nature fallacy (or naturalistic fallacy), which reminds us that we can't automatically jump from descriptions about how things are to how things should be.  Evolution, for example, has made human males stronger and more aggressive (on average) than human females. In the past, and in some places and subcultures even today, being big and bad enough to outfight or intimidate other males was a successful strategy for having more offspring.  Does that mean men should fight more, since we are, in the mindless evolutionary sense, designed for it?  Certainly not.  The fact that belligerence was a successful strategy in the past doesn't mean it's the right way to act.  Is does not equal ought.

Nature only seems care about what works, not what's right.  However, this doesn't mean nature is irrelevant to morality.  We can't simply ignore the laws of nature, or the realities of human nature, when we decide how we should act.  We can't for example, decide that it's wrong to ever eat any part of another living thing.  We would starve to death. 

On a less drastic level, it's important to know as much as we can about human nature, to gain insight into why we have ethical preferences all.  Is our sense of morality a universal part of human nature, with deep roots in our evolutionary history?  Or are humans born a blank slate, learning the socially constructed rules of our particular culture?  In some circles, it's heresy to claim that human behavior has any intrinsic basis.  It smacks too much of old theories justifying racism, sexism, and the supposed superiority of western ways.  In the last few decades, though, it's been increasingly hard to deny that human nature has been influenced by evolution.  But it's a universal human nature, common to all people, regardless of race.  While our moral sense is obviously modified by the culture we grow up in, it was not created by that culture, at least not entirely.

If evolution is amoral and blind, how did it give us a sense of morality, a sense that some things are good or bad, right or wrong?  Let's focus one aspect of morality for now: altruism.  Altruism occurs when one animal (human or otherwise) does something to help another, at a cost to itself.  Most people feel an urge to help others, at least to some extent, especially if those others are their friends or family.  But we aren't the only animals capable of altruism. Vervet monkeys, for example, will give a loud call if they see a predator.  This warns the other members of the group to be careful, but it also increases the chance that the predator will zero in on it, and have that selfless monkey for dinner.  Wolves that have had a successful hunt will eat their fill, return to the pack, and regurgitate food for others who weren't part of the hunt.  This may be gross, but it's undeniably altruistic.

Now, we don't know if vervet monkeys and wolves feel some sense of obligation or empathy which spurs them to such selfless acts.  Both are fairly-large brained creatures, so it seems likely to me that they do.  In humans, a sense of obligation or empathy is considered a moral sense.  While I don't know if I would say wolves and vervet monkeys are moral creatures, I would say their urges toward selfless behavior could be a precursor of our more sophisticated moral sense.

But the question remains--how did this kind of behavior evolve?  Lots of people figure that animals are altruistic because it helps the group or species survive. After all, evolution is about the survival of the fittest species, right?  Well, not really.  Evolution doesn't seem to happen at the group level, except possibly in very special cases.  Here's why:  let's say you have a group of extremely altruistic monkeys, whose members always share food and help care for each others' offspring.  They always help each other, and because of that, they are a very successful group.  But there is always some variation within any group of organisms.  Occasionally, one will arise within the group that doesn't have "helpful genes".  They never help, and they take advantage of the altruism of the others.  This they will survive better, at the expense of the others.  It also means they have more offspring, who inherit their tendency to take advantage of others.  Very quickly, these non-altruistic monkeys will get more and more common in the population, until the group is no longer composed mostly of altruists.  To the extent that acting for the good of the group is not conducive to survival and reproduction of the individual, it is not--to use the evolutionary biologist's term--an evolutionarily stable strategy.

Actually, what matters most in evolution is not the even success of the individual, but of particular genes.  Individual living things are ephemeral--most only live a few years at best. An individual's particular combination of genes are also ephemeral.  In sexually reproducing organisms, each one has a unique genome, a mix of the genomes of their parents.  If they reproduce, they will pass 50 % of their genes on to each of their offspring, and each of them will have their own unique combination of genes.  What lasts across generations are individual genes.  For the last few billion years, genes that happen to be good at getting themselves replicated have increased at the expense of genes that weren't as good at replicating.  Over time, the world has come to be populated by organisms whose genes are good at replicating themselves.  As Richard Dawkins explains in The Selfish Gene, whole organisms are vehicles designed by genes for the purpose of replicating those genes.  Of course, neither the organism or the gene is conscious of this.  A gene has no consciousness at all, and an organism that acts in a way that spreads its genes isn't conscious of why it's doing so.  A mother alligator cares for her babies because her brain and hormones tell her to, not because she's thinking about how best to spread her genes.  This is true for people, too.  We care for our children because we feel an intense love for them, rarely considering that this love has anything to do with our genes.

Caring for children is so automatic for most people that it doesn't even seem like altruism.  It's just what you do.  But it is altruism in the sense that the parent is making sacrifices for the child.  Often big sacrifices.  Once I had a dog that had puppies.  She was a wonderful mother, and nursed them all the time.  Before long, her hair started falling out, because her puppies were getting nutrients she needed for herself.  She was sacrificing her health (albeit unconsciously) for the sake of other creatures--her puppies.  The immediate reason she did this is because she felt (and I'm convinced she had feelings) an overwhelming urge to do so.  But the ultimate, evolutionary reason she felt that way is that each one of those eight puppies held copies of her genes.  I say copies because genes can't pass themselves on.  They can only pass copies of themselves on.  This means it doesn't matter, in terms of the gene's success, that those copies are in another organism.  In fact, it works out well, because one organism can have many offspring, producing multiple copies of many of its genes (multiple copies of all of them, if it reproduces asexually, but that's a different topic). 

Today, this "gene's eye" view of evolution is often known as the "selfish gene" theory, because it was explained in the brilliant book of the same name by Richard Dawkins.  Other scientists, especially W.D. Hamilton, George Williams, John Maynard Smith, and Robert Trivers, came up with the basic idea of looking at evolution at the level of the genes.  As Richard Dawkins would readily admit, he was just explaining it.  As he would also admit, the title of the book has caused a lot of misunderstanding.  He called the book The Selfish Gene because genes tend to do whatever it takes to get themselves replicated, whether or not this is good for the individual organism.  A male preying mantis has an intense urge to mate with a female preying mantis, even though she is quite likely to bite his head off in the midst of their passion.  It's a risk worth taking, as far as his genes are concerned, because he is getting them reproduced.  As long as more genes are replicated in the long run, the misfortunes of Mr. Mantis are irrelevant to evolution.   This is the sense in which genes are selfish.  The mistake is to conclude that selfish genes always create selfish organisms.  Genes do whatever it takes to get themselves replicated.  Sometimes selfish organisms do this most effectively, but oftentimes, altruism works just as well.

We've already seen one way this is true: with parental care of offspring.  But altruism in nature goes beyond that.  If all genes become widespread by making copies of themselves, those copies don't have to be in direct offspring.  An organism's offspring, as I mentioned, have copies of 50% of its genes.  But so do its parents and siblings.  This means that if it doesn't have offspring, but helps two of its siblings survive and reproduce, the effect is the same in terms of gene replication.  This means natural selection will tend to produce organisms that act altruistically toward their relatives.  The closer the relation, on average, the more altruism.  While siblings share 50% of their genes, cousins only share 25% of them (on average, as always).  If we look at how the world works, that's exactly what tends to happen.  Some animals do take care of their siblings' offspring, but they don't spend as much time with them as their own offspring.  My aunts and uncles were all very kind and generous to me, but they didn't raise me.  They raised their own children.  That's how evolution made us.

Selection for altruism toward relatives is known as kin selection, and it accounts for most of the altruism in nature.  But it only goes so far.  It doesn't lead to absolute altruism, even toward ones children or siblings.  If there are two siblings, and only enough food for one of them to survive, kin selection theory predicts each will try take the food for itself.  Yes, if one of them lets it's sibling have the food, and then dies, 50% of its genes would have survived.  But if it takes the food itself, 100% of its genes have survived.  So, even close relatives don't share the exact same interests, genetically speaking, unless they are identical twins.  This means there's a lot of conflict in nature, even among members of immediate families.  In some cases, when an individual can spread its genes more effectively by surviving at the expense of its family members, kin altruism is selected against.  This is apparently the case in the Sand Tiger shark.  This shark gives birth to live young, but only two of them.  The shark has a double uterus, and in each branch, the shark embryos eat each other, until only one remains.  Evolution doesn't always encourage niceness, even among brothers and sisters.
This unsettling image brings up an extremely important point.  I want be perfectly clear that, while I do think evolution created most of our moral impulses, such as our urge to treat relatives well, I don't think these impulses are the best we can do morally.  As I discussed in the last post, nature is amoral.  Evolution encourages altruism when altruism is useful for spreading the most genes.  When it isn't useful, it isn't encouraged.  Our genes, in their mindless quest to replicate themselves, gave us large brains, capable of reflecting on our impulses, and (with a good bit of willpower) choosing which ones to follow, and which ones to resist.  And some of our natural impulses should definitely be resisted.

In any case, it seems likely to me that altruism between related individuals gave rise to some of our basic, morally-laden emotions, including love, the urge to nurture and protect, and our sense of loyalty to family.  In human societies, we are constantly using family metaphors to encourage bonding, cooperation, and loyalty among unrelated people.  Students in fraternities and sororities call each other brothers and sisters.  Catholic priests are called "Father".  Americans talk about our Founding Fathers, while Russian's talk about Mother Russia.  Confucius saw society as a large family, and believed that the kind of loyalty and hierarchy that made a good family (as he saw it) would also make a good society.  This extension of the family metaphor into larger groups has been a mixed blessing, of course.  On the one hand, it's built cooperative groups capable of accomplishing far more than they would have if they hadn't cooperated.  On the other hand, it can be used by tyrants to justify their power (Big Brother is watching you), and it can lead to a nasty kind of tribalism, where people abuse those that aren't part of their societal "families".

I don't want to get caught up in how the family metaphor is extended to unrelated people, at least not now.  My main point in this post is that the moral impulses humans feel have an evolutionary history that began long before humans did.  But it isn't common to all animals.  Many animals feel no impulse at all to treat other members of their species well.  If parental care isn't adaptive, they don't even feel the need to treat their own babies well. Many frogs simply leave their eggs in a pond, and then go about their business.  It's probably safe to say that this frog doesn't have any particular sense of good will or fair play toward other frogs.  However, animals that practice parental care--even solitary ones such as bears--do seem to feel an obligation to protect and care for other bears--if those bears are their own offspring.  In social animals, individuals may feel an urge to care for the rest of their family, not just their own offspring.  In many small groups of animals, most individuals are related, so they may feel a general altruism toward all their fellows (though they are likely to feel more of it towards immediate kin).

Of course, there's a lot more to human morality than altruism between relatives. We also have a sense of the sacred, of fairness, of loyalty, and of moral outrage when we think these things are being violated.  If I'm going to consider the origins of these impulses, then I have a lot more work to do.  However, I think it makes sense to start by looking at how some animals began to have the sense that they should be benevolent or cooperative to certain other animals (instead of ignoring them, chasing them away, or killing them).  One way this happened is though kin altruism.  But it's not the only way.  Unrelated animals do cooperate in nature, and some may even form friendships, develop a rudimentary sense of fairness and empathy, and trade favors.  This kind of cooperation isn't as strong as kin altruism, though, and it's prone to shifting alliances and exploitation by cheaters.  This is where social life among animals turns into a real soap opera.  But this post is long enough, so I'll talk about that in the next episode.

The Selfish Gene - Richard Dawkins

The Expanding Circle:  Ethics and Sociobiology - Peter Singer

Meerkat image © goldencolt -

Sunday, February 12, 2012

All-Natural Goodness, Part II: Does Natural = Good?

For people just tuning in to this series of blog posts (and if you are, many thanks), I've been on a kick of thinking about where morality comes from.  Is it an innate part of reality, or have we humans created it ourselves?  So far, I've examined the idea that good and bad are whatever God says they are, and found it wanting.  I've also considered the history of natural law ethics--the idea that there is a higher law in nature, discoverable by human reason, that can tell us how our laws and morals should be.  In that post, I talked about natural law as it has been seen by thinkers from Socrates, to Aquinas, to Jefferson, and concluded that that we can't conclude that morality is written into nature or reality in any simple way.  Maybe moral laws exist in the sense that they inevitably arise when thinking, feeling beings start to haggle over rules for treating each other decently.  That's plausible, but what isn't plausible to me is that detailed moral laws existed before conscious beings with preferences came along.

In this post, I want to return to the idea of intrinsic morality in nature, but from a slightly different angle.  Most people have an intuitive sense of natural law, even if they've never read a speck of philosophy.  This sense underlies the common belief that what is natural is good, and what is unnatural is bad.  Of course, most people today aren't thinking in the terms Aristotle or Aquinus did.  Some people take a religious view, thinking something like "God created nature, and nature is good.  Therefore, what is natural is good, and what is contrary to nature is bad."  These people may accept the idea that people should tame nature, but not directly contradict it.  Others focus on nature in itself, and separate it from the idea of God.  In fact, many of those convinced of the goodness and rightness of nature are not traditionally religious.  Lots of folks who gravitate toward nature and the outdoors have an reverence for the nature world that seems a lot like religion to me, even when they don't consider themselves religious.  

I understand this feeling, because reverence for nature comes, well, naturally to me.  I was one of those kids who spent my summers and weekends tromping around the woods, marveling at the wonder of it all.  Like many such people, I think nature has beauty and harmony, an implicit wisdom we should respect. It's not hard to see where this view comes from. Almost anyone thinks a mountain stream, for example, is more beautiful than a sewage drain or salvage yard. A meadow is a nicer thing to look at than a parking deck. But these are just surface appearances.  The apparent harmony and goodness of nature goes deeper than that. Examples abound of the amazing balance and stability of the natural world. For hundreds of millions of years, animals have inhaled oxygen and exhaled carbon dioxide, while plants have done the reverse; and around it's gone in an efficient, stable cycle. Examples also abound of the unintended folly of human actions. DDT seemed great until we realized it was wiping out birds. Australia is now knee deep in rabbits, toads, and camels because someone thought it would be a good idea to introduce them.  Artificial trans fats seemed just as good as naturally occurring fats, until we realized...they weren't.
It's no wonder, then, that people make the generalization that natural is good, unnatural is bad. But the idea is usually based on gut feelings more than facts, so it tends to be both strongly held and vaguely formulated. The result is that people draw conflicting, often mutually exclusive conclusions from their intuitions about the "rightness" of nature. People have appealed to nature to justify or attack just about every idea imaginable. Some assume that herbal remedies are always safer and more effective than synthetic drugs, simply because they are natural, even though there's no scientific reason to think plants evolved to provide us with medicines. Sometimes it's true that natural remedies are better, but it isn't necessarily (or even usually) true. Arsenic, mercury, and hemlock, which are all quite natural, will kill you quite dead, while synthetics like sulfa drugs have saved millions of lives. Social conservatives often justify discrimination against gays on the grounds that homosexuality is "against nature". Various forms of social Darwinism, the idea that we should let the "fittest" in society rise to the top, leaving the unfit to their fate (because that's the way nature works) are still rather common. So, while there's no doubt we can learn a lot from the natural world, it's crucial that we take this intuition and clarify exactly what it means, and what it doesn't.

I learned this lesson once at a party.  I was talking to a good friend, who has degrees in philosophy and biology, about whether it was wrong to eat animals.  As an ethical vegetarian, she thought it was. I disagreed, telling her I thought there is nothing wrong with eating other animals, because that's the way nature works. I said, "Animals eat each other throughout the natural world, so why should we be an exception?" "Well," she shot back, "infanticide, robbery, and deceit happen all the time in nature too. Does that mean it's fine for us to do those things? Whether or not something happens in nature doesn't determine whether it's ethically right"
I opened my mouth to reply...and then shut it again.  I had no retort to her argument. I had always been the type to look to nature for guidance about how the world should work, and I had never thought about things this way. But I realized she was right. The fact that lions kill other lions' cubs doesn't make it ethically right for us to kill infants. If I find it indefensible to justify infanticide by saying it happens in nature, I have to admit that justifying meat-eating on the same basis is just as groundless. The logic is the same in both cases. This realization wasn't enough to convince me it was wrong to eat meat, but I did have to abandon my favorite justification for it. 

I found out later that I had been caught red-handed committing a well known philosophical fallacy, called the naturalistic fallacy, or the appeal to nature fallacy (there's a difference, but it's too subtle to concern us here). The first to point out the problems with this way of thinking was the Scottish philosopher David Hume. Hume said that just because things are a certain way doesn't mean that things should be that way. The way he put it is that there are no logical grounds for inferring what ought to be from what is. A similar idea was put forth by G.E. Moore at the beginning of the 20th century, using a more sophisticated logical argument. Today most ethicists accept that the naturalistic fallacy is a logical error.  Of course, this doesn't mean that nature as it is has no bearing on what is right.  We obviously ignore nature at our peril. But it does means that just because something exists in nature, that does not mean it's right or good. 

With most natural processes, from colliding molecules to evolving species, it doesn't make much sense to talk about morality, because those processes happen mindlessly.  You may regret that a rock fell on you, or that a virus made you sick, but it doesn't make sense to blame them for their actions, because they have no minds.  They don't know they're doing it.  For an entity to have a moral capacity, it has to have things like awareness, preferences, and the ability to make choices.  Moral beings didn't exist on Earth until animals evolved brains sophisticated enough to have such abilities.  It seems to me that, once an animal develops sensations and preferences, it deserves some degree of moral consideration.  Moving up the scale of moral sophistication, once an animal--a human for example--realizes that other animals are capable of pleasure, pain, and preferences, and becomes able to consider and choose its actions, then we can talk about whether it is behaving morally, based on how its behaviors affect other sentient animals. 

I don't know when in the history of our world the capacity for awareness began, but at some point (long before people came along, I suspect) living things began to feel what was happening to them.  This was a revolution in nature, because it added a subjective--and eventually intellectual and moral--dimension to what had previously been the blind shuffling of matter and energy.  But this revolution has been a mixed blessing for us sentient beings. The simple capacity to feel is a double-edged sword. It introduces pleasure and satisfaction, but also hunger and pain. Because nature is blind, there is no guarantee that the pleasures will outweigh the torments. I have seen pairs of beavers (which often mate for life) carefully groom each other at dusk. Young deer romp and chase each other, and even snakes and lizards seem content when they bask in the sun. I'm convinced that pleasure and appreciation have been around far longer than we humans have. But I've also seen seagulls rob their neighbors' nests and eat the babies. Tragedy and pain are also much older than we are.

I think the romantic vision that nature is unfailingly harmonious and beneficial, and that it offers a sure guide to morality, is deeply flawed.  We need a new, more nuanced way of thinking about about nature, one that recognizes its horrors as well as its glories. I think the Hindus can teach us westerners a lesson here.  The well-known image to the right is the Hindu god Shiva. Typical of Hindu deities, Shiva assumes many contrasting forms. He is simultaneously the god of asceticism, destruction, and sensuality. In the picture, he assumes a form called Nataraja, Sanskrit for "lord of the dance". In this form, Shiva brings the world into being through an awesome cosmic dance of creation. Standing on a dwarf who represents human ignorance-our limited view of reality--he holds a drum symbolizing creation in one of his four hands, and a flame signifying destruction in the other. In Hinduism, the world emerges in the swirling play of these two forces. I think this is a perfect symbol for the way the natural world works. Like a dance, nature is an ongoing process of creation, full of rhythm, balance, and harmony. It's truly a thing of beauty, like many well-orchestrated acts of creation. But, like Shiva, nature frequently creates by destroying. In the cycle of national selection that has built the gorgeous diversity of living things, there is no safety net for those that aren't able to survive and reproduce. Survival of the fittest often means the death of the imperfect. I don't mean that's how things should be.  I'm just saying that's how they are.
Nature may be beautiful, but for the most part it's merciless. For every example of cooperation or nurturing you can find another example of predation, competition, or parasitism. This only makes sense if nature has evolved unconsciously, through a blind process that requires no planning, foresight, or feeling. Nature judges new behaviors and forms on one basis-whether or not they work. With the exception of a few animals with nervous systems, there is little evidence of any awareness in nature. It's senseless to talk about the morality of the natural world, just as it's senseless to blame a tree for falling on your house. Morality presupposes awareness and preference. Unless these abilities are involved, nature is amoral. It is neither good nor evil. It simply is.
We humans probably didn't invent pleasure and pain, or appreciation and tragedy, but we have refined them. Our species has invented sensory and aesthetic wonders, from chocolate ice cream to the Sistine Chapel. But we have also invented iron maidens and concentration camps. We've taken feelings, good and bad, to heights never seen in nature. But our world also differs from the natural world, in ways beyond intensification and refinement. In contrast to the rest of nature, we have a great deal of control over the quality of human life. 
That's one of the bonuses of our ability to imagine things that aren't immediately present. We can imagine alternatives and try to choose the better ones. I think this is the challenge of the human condition--unlike much of nature, we are at least partially responsible for what we do. We can decide how we want to live, how we should treat others, and what kind of society we want to have. Because we have foresight and choice, we have the capacity (some might say duty) to act purposefully and morally. This means it's possible for human society to progress--to improve the world, or at least our own societies. While nature makes decisions based solely on what is stable or viable, we can go beyond these criteria, and chose based on what improves the quality of the lives around us; on what is right and just. The question is whether we have the wisdom and will to do so.

Friday, February 10, 2012

All-Natural Goodness: Are there Natural Laws of Morality?

As anyone who reads this blog will have noticed, I've been obsessed lately with philosophical ideas about ethics.  In particular, I've been fascinated by this question: Why should we be ethical?  In other words, where do ethics come from?  What is it about the world we live in that dictates that we should do some things, and should not do others?  Before you cross to the other side of the street next time you see me, let me clarify what I mean. I certainly think we should be ethical.  I haven't suddenly decided there's no reason not knock over the next bank I see.  It's just that I've discovered that if you start thinking about the foundations of ethics, you run into some fascinating conundrums.

In my last post, I talked about problems with the assumption that what is ethical is simply whatever God commands.  What if God commanded you to take a rifle and shoot everyone over six feet tall?  Would that be good, because God said so?  If you say "No, God would never command that, because that is bad", then you have admitted that there must be a standard of good and bad independent of God.  This doesn't mean you can't still believe in God, and believe in God's commands, but it does mean you have to accept that, if what God commands is what is good, it must be good for some reason other than "Because I said so". 


If moral principles like goodness and justice don't come from God's will, where do they come from?  One of the most common answers is that they're an intrinsic part of nature or reality.  Socrates and Plato both believed that they were objective realities...higher realities, in fact, than the world we live in.  Plato developed the idea further than Socrates, arguing that when we recognize an instance of goodness, we are sensing a general, universal "Good"; an eternal form, of which particular instances are pale reflections.  The idea of such Platonic forms is an interesting one.  Personally, I think it's more plausible that these "forms" are creations of our minds, which can take several particular instances of a category, and then construct an image of a "perfect" or "general" version of that category.  If a child who has never seen an equilateral triangle sees many triangles with unequal sides, it's quite possible that she could imagine a "perfect" equilateral triangle.  

Perhaps the idea of Good and Justice are the same kinds of mental constructions.  But maybe they really are "out there" somewhere.  Some modern mathematicians actually are Platonists, who believe that when they find new mathematical proofs, they're actually discovering something that already had an independent reality.  Maybe they're right--maybe logic and number are intrinsic, fundamental features of the universe.  But it seems to me that it's far less parsimonious to suggest that Justice is an intrinsic feature of the universe.  I can imagine that laws of geometry or logic might be real and independent of our minds, but something as complex and apparently subjective as "Good" seems like a less likely candidate.  It requires more extensive assumptions about the nature of reality.

Both Plato and Socrates seemed to think that reason is what allows us to understand the eternal forms of Good and Justice.  They also thought that if we understand goodness and justice, we will automatically be good and just.  If that seems far fetched to you, join the club.  There's a pretty big gulf between knowing what's right and actually doing it.  I'm sitting here wearing a t-shirt that may very well have been made in some awful sweatshop.  I know I should have sprung for a more expensive "fair trade" t-shirt.  But I didn't.  Not from lack of knowledge, but from a not-especially-admirable lack of will.


Aristotle was a more down-to-earth thinker than his predecessors, and didn't believe in Platonic forms, or that simply knowing what is good will insure that someone actually is good.  Aristotle believed that all living things have a telos; a natural state or purpose to which they aspire.  "The Good" for Aristotle is for something to realize its purpose to the highest degree possible.  If an anteater is a creature whose essence is to eat ants, then what is good for an anteater is to excel at its ant-eating lifestyle.  Aristotle saw reason as the distinguishing feature of human beings (maybe he was a little starry-eyed), and he argued that what is good or virtuous for humans is to excel at reasoning.  However, he argued that people have use their reason to decide what habits are good, and then work at cultivating those habits.  In other words, he was an advocate of virtue ethics, the stance that ethics consists in cultivating virtues, or habits of goodness.  What's important for us, however, is that Aristotle didn't see "The Good" as a universal Platonic form.  He believed what was good for any particular thing depended on what sort of thing it was, and what its ultimate purpose was. 


After Aristotle, the idea that there are laws of morality in nature (or human nature) that transcend laws of particular governments, and can be discovered by reason, came to be known as "natural law".  I've been reading about natural law off and on all week, and it's a complicated subject, because there have been many versions of natural law thinking.  Here's my understanding (take it with a grain of salt).  Aristotle is often said to be the founder of natural law theory, though it seems to me that Plato and Socrates were advocates of "higher laws", and could also be said to believe in natural law.  In any case, various forms of natural law theory have been promoted by a long line of thinkers.  The Roman Stoics believed in cosmic lawfulness, and were among the first to maintain that humans were created equal (an idea that would have seemed laughable to the Greek philosophers).  The Roman statesman Cicero promoted the idea that unjust laws are out of tune with higher, natural law, and thus shouldn't be accepted as laws at all.  

St. Paul seems to have believed that all people, even non-Christians, have a sense of universal law.  St. Augustine also believed in natural law, but he believed that the world had fallen from its state of perfect natural law after the fall of Adam and Eve.  For Augustine, humankind, and the world we live in, are now characterized more by sin and evil than by goodness and justice.  St. Thomas Aquinas was much less pessimistic about human nature, and about nature itself.  In his Aquinas' day, Aristotle's writings had recently been rediscovered in Europe.  Amazed by Aristotle's insights, Aquinas tried to harmonize the old heathen's philosophy with Christianity.  Aquinas saw natural law as a subset of God's eternal law.  He believed that the highest good was to know God, but he also believed, like Aristotle, that everything in nature has a purpose, and that whatever furthers that purpose is good.  He believed that certain virtues could be discovered by reasoning about natural law, while others could only be known through faith.  Like many others before and after him, Aquinas equated what he saw as natural for humans with what is moral.  For example, he condemned homosexuality on the grounds that the natural purpose of sex and marriage is procreation.  Since homosexuals could not procreate, their behavior was seen as unnatural, and therefore, wrong.  More on this line of thinking later.


After the Renaissance, when people became more individualistic and less focused on religion, natural law theories took on a different tone, which focused more on the natural rights of individuals.  Hobbes, who famously believed that human life in the state of nature was "solitary, poor, nasty, brutish, and short", nevertheless believed in natural law.  For Hobbes, however, natural law was a very different thing than for Aristotle or Aquinas. Hobbes thought natural law corresponded to the laws rational people would naturally come to accept as the right way to live, in order to transcend the state of nature (the time when people were irrational and unconstrained in their violence).  To this end, he was the first to suggest the idea of a social contract which people could enter into to insure their basic rights and safety.  Hobbes thought that rational people would see the necessity for a sovereign, or king, who could enforce the laws that keep people from being too nasty to each other.  Hobbes was rejecting the traditional idea of the divine right of kings (a revolutionary idea, whether he meant it to be or not) and suggesting that a king's power is justified by the need for a social contract, and a sovereign strong enough to maintain order.  

Hugo Grotius, a Dutch contemporary of Hobbes, made influential arguments based on natural law regarding just war theory and the law of the seas.  Although he was a very religious man, Grotius argued that natural law would exist even if "we should assume the impossible, that there is no God or that he does not care for human affairs".  This was also quite radical, of course, because it claimed that God wasn't essential to natural and moral law.  John Locke took Hobbes' idea of a social contract, and turned it around, claiming that a king or government's power is only legitimate if it protects the rights of its citizens to "life, liberty, and property".  If it fails, the people have a right to revolt and create a new government. 

Of course, colonial Americans did just that.  In the Declaration of Independence, Thomas Jefferson summed up the natural law philosophy of his day, closely echoing Locke.  Because this is one of the most influential documents in history, it's worth quoting at length:
When in the Course of human events it becomes necessary for one people to dissolve the political bands which have connected them with another and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness. That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.
Here we see, in the founding document of what is now the world's most powerful country, all the threads of the natural law theory of the time.  These ideas, as far as I'm concerned, represented a huge leap forward in justice and liberty.  Even though some groups, such as women and slaves, were not immediately credited with that equality, or extended those rights, they have gained them over time, partly because of the power of the ideas of natural rights and natural law.  It was a tremendous accomplishment.


The Declaration of Independence was written well over 200 years ago, so it's no surprise that science and philosophy have moved beyond the ideas it expresses.  As brilliant as Jefferson and some of the other founders of the United States were, they were people of their time.  They would have had no reason to question the Aristotelian idea that there is a natural purpose to everything in nature.  They also had no reason to question the idea that human reason is a sure route to transcendent truth, and that there is such a thing as a "self-evident" idea.  Many, following Locke, would have believed that the human mind is a "blank slate".  Almost all of them believed in a God that had created the natural order of things, though some, like Jefferson, were Deists who believed God set the universe in motion and then mostly left it alone.  

In the century after the Declaration, other ideas came along that challenged some of its assumptions.  Jeremy Bentham, the founder of Utilitarianism, suggested that the ethics of an action should be judged based on its consequences--specifically, whether or not it increases the amount of happiness in the world--instead of whether it is dictated by natural law.  Bentham was scornful of the idea of natural rights, calling it "nonsense on stilts".

Even more importantly, Darwin realized that the amazing diversity of life had nothing to do with an intrinsic order in which every living thing had its purpose and its role to play.  He saw that nature is not eternal and unchanging, and that living things, including humans, could have evolved through the blind process of evolution by natural selection.  In Darwin's view of nature, species do not exist to serve some Aristotelian purpose.  A species exists because it evolved to fit into its ecological niche.  While a species may come to play a role in nature, because it inter-adapts with other species that may come to rely on it, this is accidental.  Even if cows can't live without grass, grass didn't evolve to feed cows.

In the 1800's, then, it came to seem less likely that natural order was due to a divine architect who had written natural law and natural rights into the blueprints, to be discovered by the pure power of human reason.  Humans could now be seen as another on of the animals, albeit a very brainy one.  The human mind could be seen as a product of the blind process of evolution.  This means there is no guarantee that reason is a window into eternal truth, or even that we are especially reasonable creatures.  Smart, yes, but not necessarily wired to recognize eternal truths.  Besides, science--which was based on observation instead of pure reason--was chalking up one triumph after another.  This started to make traditional philosophy look plodding and outmoded. 

And then there were people like Jeremy Bentham, who raised a very good question: does it really make sense to say that morality is based on some transcendental natural law?  Aristotle and Aquinas' view of the natural purpose of humans and other animals--one major source of natural law thinking--had been dealt a serious blow.  Some were even questioning whether God was necessary at all.  If humans and other creatures were not put on Earth for a certain purpose, what sense did it make to talk about ethical laws having a reality unto themselves?  Are moral laws somehow written across the sky?  Or should we just follow Bentham, and say that ethics are simply a way of maximizing pleasure and minimizing pain? 


Here's how I see it, for what it's worth.  The modern scientific view suggests that the universe, and life on earth, has evolved in ways that can be explained entirely in terms of blind physical laws. While I'm not going to take the leap of faith required to state flatly that there is no God, or that there is no conceivable purpose to the universe, it seems to me quite plausible that there is no intrinsic purpose.  I've read about science and nature for years, and never seen something that seems like a clear-cut purpose to me.  If nature wasn't created with a purpose in mind, and to the extent that its order can be explained by physical laws instead of divine design, it doesn't make sense to assume that there are natural laws of morality written into the universe.  Goodness, truth, and justice are great things, but not because they are fundamental to nature in the way that light and matter are.

The only version of natural law that makes sense to me is similar to that of Hobbes, who saw natural law as reflecting the conclusions rational people will naturally come to when deciding how to organize their that it's tolerable to live in it.  This view doesn't see natural law as something fundamental in nature, but as something that arises out of nature, when people with the ability to reason come along.  Some people would say this doesn't seem much like a natural law.  Maybe not, but it doesn't really concern me whether or not ethical laws are fundamental to reality.  If ethical laws are something we invent because it makes sense to do so, well, good for us. Or, perhaps what is really a fundamental natural law is not the presence of positive natural law, but the absence of something:  the absence of any good reason to think my interests are any more valuable than yours are, and that I shouldn't treat you ethically.  

Actually, I think science and nature, as well as pure reason, can tell us a lot about ethics, even if there really isn't a natural law of morality.  We are a part of nature, and if we don't understand it, we're likely to make mistakes with ethical consequences.  Also, our ethical sense is based on emotional impulses, such as empathy, fairness, guilt, and even disgust, that are a product of our evolution as social animals.  So, we need to understand the intersection between nature and ethics.  However, we have to be very careful when looking to nature to decide what is right and good.  There is a lot of good in nature, but not everything in nature is necessarily good.  Skeptical?  Stay tuned...