As a topic, the is-ought (or fact-value) distinction has been beaten to death. It is so straightforward that it is surprising to see a very intelligent person like Sam Harris completely misunderstand it.
First, let’s go over the is-ought distinction. Famously pointed out by Hume, the idea is that no set of ‘is’ statements can lead to an ‘ought’.
The person is dying.
This medicine on the counter can save her.
-> the person ought to take the medicine
This simply doesn’t follow unless you believe the person ‘ought’ to live.
Now, to show that I don’t misunderstand Sam, I’m going to steelman his position as is done in the rationalist community.
We start from a naturalist claim. Consciousness is a natural phenomenon that each of us experiences and cannot really ignore. Once we acknowledge that consciousness exists and that we are conscious beings, we must acknowledge the reality that we are programmed to avoid suffering. To illustrate this point, Sam will note that we will pull our hand off a fire. In other words, consciousness is the proximate cause of human behaviour (as opposed to the root cause, which is the big bang or whatever happened at the beginning of the universe). That cause works in predictable ways that science can study. Therefore, we can posit that the subject of a science of morality is to figure out how to achieve the types of goals that are built into the structure of consciousness in the most effective way.
The only axiom needed is that navigating away from the worst misery and suffering is a good place to start such a science.
Sam compares this field to the study of medicine, which most acknowledge is a science. The goal of medicine is to figure out what substances will cause a human to live a healthier life. So medicine generally concerns itself with efficacy of taking pain away from living things.
The only axiom underpinning medicine is that it is worthwhile to study how to keep living things, specifically human beings, healthy.
Therefore, there is nothing more special about the science of morality than the science of medicine.
Now, I will show you why Sam is wrong. What Sam seems to miss is that the ‘ought’ itself is the moral claim and is not part of the science. Simply put, medicine does not tell you that you ‘ought’ to give the dying man this pill that will save him. It only tells you that doing so ‘will’ save his life. This explains why we need the hippocratic oath in addition to the study of medicine. It also explains how Nazi doctors, who performed extremely immoral scientific studies on people, were in fact practicing a form of science. If Sam wants to study what will cause the greatest well being in conscious minds, that’s fine. There is nothing that his science will compel us to do, until we bring our values to the table.
For instance, if the person in the original syllogism who was dying was a ‘bad’ person, we arguably ought not to give her the medicine. However, the scientific fact that medicine would save her life remains. Or suppose the person is really old and wants to die, she might choose not to take the medicine. Again the scientific fact about the medicine saving her life remains. The same is true of Sam’s science of morality. It will tell you what things maximize well being without telling you what to do about them. It might be true that acting in a way that causes humanity to suffer will indeed decrease the general well being of conscious agents (indeed this seems almost tautological) and is against the desire of each agent. However, it does make a rational agent compelled to act one way or another. For instance, we can easily imagine a situation where one conscious agent wants to hurt another, because they are a psychopathic serial killer. We can imagine putting the psychopathic serial killer on drugs that will cause them to stop wanting to kill the victim. This will add to the well being of the victim and, if the drugs are really good, they might also add to the well being of the killer. However, during that intervention, forcing the drugs down the throat of the killer, will certainly add to the suffering of the killer, who wants nothing more than to strangle his victim. I am sure what the moral answer should be, but the moral science will permit me no such claims. It will only be able to measure all of the well being of all the agents and tell me how all the agents respond to different treatments.
Sam might be right, that we generally understand that the goal of medicine is helping people lead healthier lives. However, that doesn’t acknowledge where the science is a science and where it is just the overwhelming social consensus of what to do with the knowledge. He can even claim that such a distinction is not useful in medicine. although the entire field of bioethics would seem to discredit such a claim. It is also true, that any study of morality must rely on a solid foundation of facts. Those facts might belong to the field of science of morality, which will tell you the consequences of actions on conscious beings. You cannot make an informed moral decision without the facts. So the facts are a necessary, but insufficient condition for moral claims.
If Sam were right, then a science of Sadism would compel me to be a sadist. Yet, we might want to study what causes suffering and how to cause the greatest amount. This field might spawn other useful subfields such as dentistry. The choice of the field of study is in itself a value judgement, in so far as it prioritizes time across an infinite array of fields and focuses on some particular domain. For example, we can agree that the government should sponsor basic research in astronomy, but not astrology. People can disagree with that statement in many ways, but none of those claims and statements are about facts. The facts remain, that astrology studies occult things and astronomy studies the cosmos. Choosing between these disciplines is a valid choice and a sufficiently functional society can choose to allocate its resources into either field.
There is a separate argument to have with Sam’s choice of axiom. We can imagine a drug that will give everyone the conscious feeling of well being, and yet it might be immoral to force everyone to take it.
I know that Sam is very smart and so I have tried as hard as possible to defend his position in a strong way. If anyone can help me make his case stronger, that is welcome.