Personal experience and claims

A critical difficulty with appealing to personal experience when considering many claims is that there will be many competing explanations for the observed behaviour, event, or phenomenon, but personal experience offers no feasible means of ruling out all but the true explanation. Our reviews or analyses of our own personal experience or our attempts to assess the reports of other actors’ personal experience can lead us to fail in reasonably reaching a competent conclusion about the claim(s) in question.

Consider, for example, the claim that we will recover more rapidly from a common cold or even be able to successfully resist coming down with colds by regularly taking a certain daily dosage of Vitamin C tablets, and that there is no penalty to be paid by taking the dosage recommended by proponents. Neither our own experience nor the anecdotes of others’ provides us with a proper basis to make a judgement about this general claim as to whether it is true beyond all reasonable doubt, or even whether it has a substantial likelihood of being true. The evidence from scientific studies supports a general absence of efficacy, moreover, the research should engender some level of concern about long-term health effects from taking the suggested ‘megadoses’.

Furthermore, imagine the case many years’ ago of claims made by some people resistant to the idea of compulsory seatbelt-wearing in (moving) motor cars that, in their experience and the experience of their peers, putting up with the ‘inconvenience’ – in their eyes – of mandated seatbelt-wearing was not justified, as they did not believe that it would make they or their families appreciably safer and might even bring about deaths or severe injuries which would not have otherwise happened.

It is now well-accepted – an evidence-based belief – that overall road-users are much more likely to survive and to survive with less serious injuries in most crash situations, aided by the wearing of an appropriately-worn restraint. Anyone who ‘by virtue’ of using their own personal experience and/or attending to the anecdotes of others believed wearing seatbelts was an imposition which wasn’t merited was mislead by unaided human judgement and was simply wrong. They may well have held to this now-demonstrated error with a great deal of confidence.

This is not to say that human beings are useless in perceiving and observing things that go on around us, and in many of the judgements and inferences we make about events and situations. Clearly there are many circumstances in which we can and do successfully rely upon our own sensory experiences and the interpretations we make of those experiences. What is at issue here is the limitations of personal experience, testimonials, and anecdotes as evidence with which we can evaluate the truth or acceptability of particular claims.

For instance, if we would like to know about the effectiveness, safety, and the costs and benefits of fluoridization of our civic water supply, our best bet is to find out what the experts’ evaluation is of the scientific research on the subject. The same applies with concerns about flu shots giving patients a nasty dose of influenza (and thereby discouraging all those who should have an inoculation from being injected) or anxieties about brain cancer and the extensive use of portable phones.

There may be times where the research evidence available is very scratchy or non-existent, and in such circumstances it would be appropriate to exercise caution and even to, in some instances, withhold use of the substance, technology, or action until a clearer picture emerges about the matter and shows the unease is or is not likely to be verified – this assumes that the concerns had some plausible foundation to begin with.

The proper role of personal experience, testimonials, and anecdotes most often is to bring to mind hypotheses which should be meaningfully tested – subjected to the scrutiny of scientific inquiry.

it is probably a wise move not to underestimate our ability as human beings to confuse or mislead ourselves.

Keep handy the following two phrases: “I was wrong”. and “I don’t know”.

(see also: anecdotal evidence, testimonial, science, scientific approach, falsifiability, testability, pseudo-science)