Sean Carroll -- a prominent cosmologist at CalTech -- has written an
excellent critique of Sam Harris's
TED talk on science and human values.
In his comments at TED, Harris contends that the perceived distinction between science and moral judgment is "an illusion," which has led many secular thinkers to embrace a dangerous kind of moral relativism. According to Harris, scientific truths can tell us an awful lot about the well-being of conscious creatures and, as a result, inform our understanding of human morality. The "facts" will point to the superiority certain moral frameworks and tell us which system of morality fail to promote well-being.
Caroll takes exception to this view:
Morality and science operate in very different ways. In science, our judgments are ultimately grounded in data; when it comes to values we have no such recourse. If I believe in the Big Bang model and you believe in the Steady State cosmology, I can point to the successful predictions of the cosmic background radiation, light element nucleosynthesis, evolution of large-scale structure, and so on. Eventually you would either agree or be relegated to crackpot status. But what if I believe that the highest moral good is to be found in the autonomy of the individual, while you believe that the highest good is to maximize the utility of some societal group? What are the data we can point to in order to adjudicate this disagreement?
In his extended
response to Carroll and other critics, Harris argues that morality must arise from a certain ethical premises regarding the value of "well-being," just as science must be premised on the value of logical coherence. Thus, we can and should dismiss as "imbeciles" those who argue against the premise that well-being the fundamental value upon which our moral judgments must be based.
As Carroll rightly points out in his
second post, however, Harris seems to be straying off course. People clearly disagree over what constitutes human "well-being." Harris cleverly bypasses this point by assuming that there are - or
can be - definitive measures of well-being.
The bigger problem with Harris's argument, though, is that he hasn't really solved the problem that he identifies: namely, that moral subjectivity leads to a dangerous kind of moral equivalence, which ultimately jusfies immoral actions.
My own view is that you generally can't convince people to change their minds on fundamental moral questions by simply asserting the objectivity of premises with which they disagree. You must convince people by finding
common premises and deducing your conclusions therefrom. Telling your intellectual opponents that their morality is
objectively wrong based on our scientific understanding of the world doesn't make the world less dangerous. Nor does it automatically lead to moral consensus.
Carroll explains:
The problem, obviously, is that we don’t all agree on the assumptions, as far as morality is concerned. Saying that everyone, or at least all right-thinking people, really want to increase human well-being seems pretty reasonable, but when you take the real world seriously it falls to pieces. And to see that, we don’t have to contrast the values of fine upstanding bourgeois Americans with those of Hitler or Jeffrey Dahmer. There are plenty of fine upstanding people — you can easily find them on the [I]nternet! — who think that human well-being is maximized by an absolute respect for individual autonomy, where people have equal access to primary goods but are given the chance to succeed or fail in life on their own. Other people think that a more collective approach is called for, and it is appropriate for some people to cede part of their personal autonomy — for example, by paying higher taxes — in the name of the greater good.
I think the issue of redistributive taxation offers an excellent challenge to Harris's view of objective morality. After all, the most controversial moral questions often exist in the realm of the social sciences rather than the physical sciences.
In economics, there remains an important distinction between positive analysis and normative analysis. Positive analysis seeks to explain the world
as it is, while normative analysis seeks to describe the world as it
ought to look. (This distinction can be traced back to David Hume's
is/ought problem.)
Nowhere is the barrier between positive analysis and normative analysis more apparent than in discussions of efficiency and equity. Economists often explain that positive economics can inform us about the efficiency trade-offs from redistributive taxation, but it
cannot tell us anything about the appropriate level of equity in a society. Different economists will come different conclusions regarding the "best" level of taxation in a society based on their view of equity.
When we look at different kinds of policy interventions, each of us employs her our own evaluative criteria. You may be willing to accept more inequality in order to create more economic growth, while I may be willing to accept a lower level of growth in order to achieve greater equality. No matter how much data we collect - or how many econometric models we construct - empirical investigation can never tell us which of these moral preferences is
correct in an objective sense.
The only thing that we can do is try to
agree on certain ethical premises and go from there . . .