The first is philosophical: Demarcation is crucial to our pursuit of knowledge; its issues go to the core of debates on epistemology and of the nature of truth and discovery. The second reason is civic: our society spends billions of tax dollars on scientific research, so it is important that we also have a good grasp of what constitutes money well spent in this regard. Should the National Institutes of Health finance research on “alternative medicine”? Should the Department of Defense fund studies on telepathy? Third, as an ethical matter, pseudoscience is not — contrary to popular belief — merely a harmless pastime of the gullible; it often threatens people’s welfare, sometimes fatally so. For instance, millions of people worldwide have died of AIDS because they (or, in some cases, their governments) refuse to accept basic scientific findings about the disease, entrusting their fates to folk remedies and “snake oil” therapies.

It is precisely in the area of medical treatments that the science-pseudoscience divide is most critical, and where the role of philosophers in clarifying things may be most relevant. Our colleague Stephen T. Asma  raised the issue in a recent Stone column (“The Enigma of Chinese Medicine”), pointing out that some traditional Chinese remedies (like drinking fresh turtle blood to alleviate cold symptoms) may in fact work, and therefore should not be dismissed as pseudoscience.