pragmatic fallacy - The Skeptic's Dictionary (original) (raw)
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The pragmatic fallacy is committed when one argues that something is true because it works and where 'works' means something like "I'm satisfied with it," "I feel better," "I find it beneficial, meaningful, or significant," or "It explains things for me." For example, many people claim that astrology works, acupuncture works, chiropractic works, homeopathy works, numerology works, palmistry works, therapeutic touch works. What 'works' means here is vague and ambiguous. At the least, it means that one perceives some practical benefit in believing that it is true, despite the fact that the utility of a belief is independent of its truth-value.
The pragmatic fallacy is common in "alternative" health claims and is often based on post hoc reasoning. For example, one has a sore back, wears the new magnetic or takionic belt, finds relief soon afterwards, and declares that the magic belt caused the pain to go away. How does one know this? Because it works! There is also some equivocation going on in the alternative health claims that fall under the heading of "energy medicine," such as acupuncture and therapeutic touch. The evidence pointed to often uses 'works' in the sense of 'the customer is satisfied' or 'the patient improves,' but the conclusion drawn is that 'chi was unblocked' or 'energy was transferred.'
There is a common retort to the skeptic who points out that customer satisfaction is irrelevant to whether the device, medicine, or therapy in question really is a significant causal factor in some outcome. Who cares why it works as long as it works? You can argue about the theory as to why it works, but you can't argue about the customer satisfaction or the fact that measurable improvements can be made. That's all that matters.
It isn't all that matters. Testimonials are not a substitute for scientific studies, which are done to make sure that we are not deceiving ourselves about what appears to be true. It is especially necessary to do controlled studies of alleged pain relievers to avoid self-deception due to the placebo effect, false impressions of placebo effects, post hoc reasoning, or the regressive fallacy. We may not want to question too deeply the felt relief, but we must question the cause of that relief.
It is easy to understand why someone with "terminal" cancer who seeks out an "alternative" treatment and finds the cancer goes into remission soon afterwards would attribute miraculous causal efficacy to the "alternative" treatment. However, if the "alternative" treatment is not really the cause of the remission, then others who seek the treatment will be filled with false hope. Of course, those patients who try the same treatment but who die anyway are not around to tell their story. Their surviving loved ones may even claim that the only reason the treatment did not work was that the patient came to it too late. The only way to know for sure whether the treatment has causal efficacy is to study its application under controlled conditions. Testimonials regarding how well the treatment works may be heartfelt, but they can be dangerously misleading.
One of the most common errors made in reasoning that some therapy works because of a felt or measurable improvement soon after getting the therapy is that one ignores other relevant possible explanations. A person who has tried several things to relieve some health problem might ignore the possibility that either the problem resolved itself (went away on its own) or some earlier therapy finally kicked in and was the real cause of the relief.
For practices like astrology, numerology, and palmistry, 'works' means little more than that one can find some way to make sense out of the vague or ambiguous claims practitioners make. Here there is the likelihood of ignoring the role of subjective validation in defending these ancient superstitions.
Last updated 14-Jan-2014