Map of life expectancy at birth from Global Education Project.

Sunday, December 18, 2005

Truth

So it turns out that the claim by Korean scientist Hwang Woo-suk to have created human embryonic stem cells by cloning adult somatic cells may be fraudulent. Whenever such spectacular allegations of scientific fraud surface, some people will raise questions about the integrity of the scientific enterprise, or even the validity of the entire structure of scientific belief.

On the contrary, this incident cogently demonstrates the power of science. Either it is possible to create human embryonic stem cells by the methods Hwang claimed to have used, or it is not. If it is not, other scientists will discover that they cannot reproduce Hwang's results, and that will be the end of it, regardless of the denoument of this case. If it can be done, it will be done, even if Hwang in fact did not do it.

Some people think that we social scientists have a different view of truth than so-called "hard scientists" like biologists or physicists. We do not. (I acknowledge some embarassing departures from the epistemological consensus by some people who called themselves social scientists, particularly during the 1980s and 90s. Fortunately, the era of transgressive hermeneutics appears to be receding in the rear view window.) We are however perhaps somewhat more alert than other kinds of scientists to the existence of various kinds of truth.

The behavior of human cells when subjected to various manipulations, like the composition and motions of the heavenly bodies or the quantum states of the beryllium atom, is out there to be discovered. Although some people may have opinions about these matters that differ from scientific findings, it would be senseless to think of these truths as socially constructed or culturally dependent. (Of course, their importance or meaning to people might be.)

However, questions like the prevalence of depressive disorder or how best to treat it, or the nature and extent of racial disparities in health care, are quite different. Depressive disorder, like most of the psychiatric diagnoses, is defined as whether or not a person reports a certain percentage of a list of subjective feelings and sensations, at levels of intensity which are generally defined qualitatively. While people have various theories about specific, measurable biological states that might correlate with getting a diagnosis of depression (such as a "deficiency" of serotonin in certain parts of the brain) there is no convincing evidence for any of these. The disease of depression, like the personality disorders, is indeed socially constructed, by a consensus of psychiatrists assigned quite frankly to the task of constructing it. The definition of whether depressive disorder responds to various treatments is likewise socially constructed, as whether people's responses to a list of questions change by a certain arbitrary amount. One can easily and quite defensibly decide to use different criteria for diagnosing depression or the remittance of depression, whereupon the prevalence of the disorder and the effectiveness of treatments will also change. (Note that this is not true of all diseases.) Indeed, it is possible to make the disease of depression go away altogether simply by denying the ontological status of the bundle of observations that constitute it.

Then there is the realm of ethics -- what ought to be, including how people ought to behave, and what we ought to desire. Truths of the first kind -- such as our origin in biological evolution, or how people of various cultures and personal characteristics respond to ethical puzzles -- may inform ethical discussion but cannot finally settle ethical questions. Truths of the second kind -- what cases belong to certain categories -- also are obviously very important in ethical discussion but there is often no good way of settling them.

Scientists sometimes claim to have settled questions based on their findings of the first kind, when in fact those findings rest on truths of the second kind, and can be challenged on that basis; or else their prescriptions depend on ethical choices which may be made differently. Critical thinking depends on being able to keep these kinds of truths separate, and to process each of them in the appropriate way. So it is possible to criticize the scientific enterprise, to make claims about science having biases, or leading society astray in some way, without denying the epistemological claims of science.

When I talk about democratizing science, I don't mean deciding on scientific truth by taking a vote, or anything remotely like that. I hope we can have more discussion here about what I do mean, and what the idea of democratizing science means to some of you who read this.

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