First Sam Harris in Project Reason:
[M]any people strongly objected to my claim that values (and hence morality) relate to facts about the wellbeing of conscious creatures. My critics seem to think that consciousness and its states hold no special place where values are concerned, or that any state of consciousness stands the same chance of being valued as any other. While maximizing the wellbeing of conscious creatures may be what I value, other people are perfectly free to define their values differently, and there will be no rational or scientific basis to argue with them. Thus, by starting my talk with the assertion that values depend upon actual or potential changes in consciousness, and that some changes are better than others, I merely assumed what I set out to prove. This is what philosophers call “begging the question.” I am, therefore, an idiot. And given that my notion of objective values must be a mere product of my own personal and cultural biases, and these led me to disparage traditional religious values from the stage at TED, I am also a bigot. While these charges are often leveled separately, they are actually connected.
I’ve now had these basic objections hurled at me a thousand different ways—from YouTube comments that end by calling me “a Mossad agent” to scarcely more serious efforts by scientists like Sean Carroll which attempt to debunk my reasoning as circular or otherwise based on unwarranted assumptions. Many of my critics piously cite Hume’s is/ought distinction as though it were well known to be the last word on the subject of morality until the end of time. Indeed, Carroll appears to think that Hume’s lazy analysis of facts and values is so compelling that he elevates it to the status of mathematical truth:
Attempts to derive ought from is [values from facts] are like attempts to reach an odd number by adding together even numbers. If someone claims that they’ve done it, you don’t have to check their math; you know that they’ve made a mistake.
This is an amazingly wrongheaded response coming from a very smart scientist. I wonder how Carroll would react if I breezily dismissed his physics with a reference to something Robert Oppenheimer once wrote, on the assumption that it was now an unmovable object around which all future human thought must flow. Happily, that’s not how physics works. But neither is it how philosophy works. Frankly, it’s not how anything that works, works.
Carroll appears to be confused about the foundations of human knowledge. For instance, he clearly misunderstands the relationship between scientific truth and scientific consensus. He imagines that scientific consensus signifies the existence of scientific truth (while scientific controversy just means that there is more work to be done). And yet, he takes moral controversy to mean that there is no such thing as moral truth (while moral consensus just means that people are deeply conditioned for certain preferences). This is a double standard that I pointed out in my talk, and it clearly rigs the game against moral truth.
Sean Carroll's rejoinder:
I wanted to try to clarify my own view on two particular points, so I put them below the fold. I went on longer than I intended to (funny how that happens). The whole thing was written in a matter of minutes — have to get back to real work — so grains of salt are prescribed.
First, the role of consensus. In formal reasoning, we all recognize the difference between axioms and deductions. We start by assuming some axioms, and the laws of logic allow us to draw certain conclusions from them. It’s not helpful to argue that the axioms are “wrong” — all we are saying is that if these assumptions hold, then we can safely draw certain conclusions.
A similar (although not precisely analogous) situation holds in other areas of human reason, including both science and morality. Within a certain community of like-minded reasoners, a set of assumptions is taken for granted, from which we can draw conclusions.