Sam Harris has posted "Toward a Science of Morality" and "Moral Confusion in the name of Science" to reply to some philosophical questions. He is finishing up a book on this subject, and he outlined some highlights at the 2010 TED conference .
As a philosopher and a humanist who is sympathetic to Harris’s efforts here, I offer some general comments. Harris is quite right that unless a naturalistic humanism can be grounded in science, humanism has nothing helpful to say about our planetary moral problems. We don’t have his book to read yet, but Harris is already defending himself in fairly specific terms. But I’d like to step back for an overview of the big picture. There is a good reason why the big philosophical guns are turning against Harris.
The last great eruption of naturalistic ethics, that actually made a major impact in the real world, was Social Darwinism. The fit rich deserve their wealth, the unfit poor should die off, and eugenics can speed things up. A truly ugly philosophy. Not without reason do religious people recall Social Darwinism as a dangerous naturalistic ethics. Many people suppose that Social Darwinism is about the best one could expect from humanism.
The philosophical problem with Social Darwinism was not its (correct) premise that human evolutionary history is crucial for understanding human morality. It was also based on two other questionable premises: that ethical and political judgments should be inferred from the foreseen trajectory of evolution, and that morality should be regarded as a social property of large groups rather than a capacity possessed by separate individuals.
You can easily see how to derive Social Darwinism: if moral progress depends on the natural evolution of the group, and if the struggle for survival drives our natural evolution, then surviving best is morally best. All individuals have to do is compete as hard as they can — their private morality is irrelevant and can only get in the way of success. The group that emerges as the winners can be called "moral" but only because they are the winners, and not because they were trying to be moral. In fact, the less individuals worry over morality, the better they might do.
Social Darwinism was repulsive to many philosophers, and different strategies to destroy it eventually worked. These strategies are now in play against Harris today. Not that Harris is suspected of Social Darwinism — no signs of that! All the same, philosophers can’t resist picking up rusty weapons just out of habitual reflex.
What worked to destroy the philosophical credibility of Social Darwinism? Three tactics were most effective:
First, "don’t use nature as a moral guide". Social Darwinism imitated Christianity’s natural law theory and subtracted God. Natural law theory said that humans should follow God’s design of the world. Subtracting God and adding evolution, we get "it is best for humans to follow the evolutionary design of the world". So, the philosophical counter-tactic is "nothing natural is therefore right". Hume’s "Is-Ought" distinction is invoked to enforce this tactic.
Second, "don’t infer morality from any evolution". Social Darwinism focused only on natural evolution, and that was a mistake. Just because we humans do something naturally, that doesn’t automatically make it right. All the same, we are cultural too. Humans do culture naturally, and morality is part of culture, so humans do morality naturally, learning from infancy and all throughout our lives. Why can’t we try to infer morality from examining cultural evolution? All the same, the philosophical counter-tactic is “just because it evolved that way, can’t make it right”. The fact that cultures endlessly disagree over morality is offered in evidence, too.
Third, "don’t think that morality is essentially social". Social Darwinism treated morality as a group phenomenon concerning social relationships in a cultural setting. Societies are not real things over and above people, but social relationships are quite real because people do sustain cooperative activities with each other. Here, philosophers are divided. Some philosophers see how morality is primarily social in nature. On the other hand, most philosophers think (following Christianity) that morality is entirely an individual matter, and that whether one is moral only depends on characteristics of each individual separately (this is a legacy of Kant as well). So, the typical philosophical counter-tactic is "morality is entirely a subjective individual matter". The fact that people endlessly disagree over moral matters is offered in evidence, too.
Finally, philosophers combine all three counter-tactics to obstruct any naturalization of morality. Look, they say, if morality existed in nature, then it would be objective enough for science to study it. Yet morality isn’t in nature – its existence depends on human beings, either collectively or individually. And look how there is endless disagreement about morality, never to be eliminated. So no other methodology, besides science, could ever help either! These sorts of arguments now confront Sam Harris.
What is a humanist to say? I have some suggestions, following the lead of a great philosopher, the pragmatist and humanist John Dewey . Dewey has debts to two other great naturalists, Aristotle and John Stuart Mill. But Dewey was the first major philosopher to offer a completely evolutionary philosophy of society and ethics.
POINT ONE: Because humans are entirely natural beings, and humans do morality naturally in their social relationships , then morality has plenty of objectively real and natural existence to be the subject of scientific investigation. Morality does not exist in some unnatural world of spirits, souls, minds, consciences, free wills, or any other left-over religious notions.
POINT TWO: The scientific study of morality is NOT the same as the scientific effort of ethics. Morality as a natural phenomena can be objectively studied, without immediately drawing conclusions about finding the better morality. The social and cognitive sciences already do this work. Unfortunately, only relativism results from arbitrarily halting at that stage. We can do more. The scientific effort of ethics is the additional effort to build on such knowledge for investigating how morality can be improved, experimenting to see how social welfare may be increased. The analogy of construction and engineering helps clarifies the relation of morality and ethics. People naturally do construction, of many things. How people construct things can be objectively studied. But the extra effort to figure out improvements to construction techniques is the discipline of engineering. Similarly, ethics is the inquiry into better morality techniques.
POINT THREE: Just because people and cultures now have big moral disagreements does NOT mean that scientific ethics is impossible – it just means that we have not been doing ethics well enough. Should we say that just because people disagree over building bridges, and cultures build quite different kinds of bridges, means that a science of engineering is impossible? It is precisely because we can objectively study bridge construction that we can be thinking about better bridge engineering. There is no "Is-Ought" dichotomy to worry about! Only because humans already build bridges can we learn how we ought to build bridges.
POINT FOUR: Just because people would like to think that morality is entirely subjective and their own personal right, does NOT make this notion correct. Individuals are just as dumb about morality and ethics as individuals as they are dumb about any other subject if left to themselves. People are only intelligent in communicating, inquiring, and learning groups. The notion that a lone person can be a proper moral judge is a leftover from some religions. Social morality exists to sustain cooperative social relationships, and morality can be objectively evaluated by that standard. If philosophers want to only talk about some bizarrely unnatural private morality, they are just changing the subject and increasing the amount of irrationality in the universe.
POINT FIVE: When philosophers, or anyone else, say that morality can’t be objective because of disagreement, they are just giving up. Their minds stop working, and they announce "Relativism" as if some oracular wisdom has been handed down. Actually, there is plenty of cross-cultural agreement on matters of basic morality , and where there is disagreement, that is precisely why we need scientific ethics! To complain that we don’t yet have complete agreement on proper standards of social welfare would be like complaining that no one should have been doing chemistry 200 years ago, because no one could first agree on the basic elements of matter. Scientific ethics is experimental inquiry and does NOT require first knowing "which culture is the best one". Chemistry got started just fine without knowing all the elements first.
Humanism is not going to collapse back into Social Darwinism or cultural relativism, whose fallacies have been exposed. Humanism IS capable of doing better – IF we scientifically study morality, and undertake the extra effort of doing scientific ethics.