A large number of people including professionals tend to rely on anecdotes, sometimes personal encounters, as evidence which is a slippery terrain. Even a string of anecdotes may not constitute evidence unless there are other corroborating aspects. Often, it is misused to malign or judge people
Several anecdotes strung together don’t create compelling logic, and one anecdote creates no grounds for sweeping generalization – I wrote this several years ago. When I revisited this recently, I began doubting if this observation can be made without qualifications as I did when I wrote this. In what follows, I am thinking afresh on the matter.
First some qualifications. I understand now that there is not just proof but standards of proof. In the world of standards of proof, it is commonly held among those who consider themselves scientists that mathematics employs the most rigorous standards of proof. Even other ‘hard’ sciences are not thought of as using such a rigorous standard of proof. This is extremely important to always bear this in mind, especially as we evaluate any ‘evidence’.
Let us start with a basic definition given by Oxford Dictionaries – the available body of facts or information indicating whether a belief or proposition is true or valid. Merriam-Webster dictionary offers a different definition, more than one in fact – an outward sign (indication), something that furnishes proof (testimony), one who bears witness. MW also offers many synonyms which are interesting to examine – attestation, confirmation, corroboration, documentation, proof, substantiation, validation and a few more – (https://www.merriam-webster.com/dictionary/evidence). The Cambridge English Dictionary sees evidence as “one or more reasons for believing that something is or not true” (https://dictionary.cambridge.org/dictionary/english/evidence).
This done, we can get down to the business of examining anecdotal evidence. As I have mentioned in the title, any evidence is evidence of something, just as when we talk of percentage, the automatic question is ‘of what’. If we lost sight of this umbilical cord, we will wander only in darkness although we may be convinced that we are basking in brightness.
We encounter anecdotal evidence almost every day. It is very common to see any number of people believing fiercely in something based only on anecdotes, what they have themselves encountered and what they have gotten to know through their networks, implicitly thinking that these exhaust the universe of possible explanations. An Indian-American told me that ‘all Indians living in the US are very successful’, because these are the people she encounters in her life. Yes, the problem here is more than the misuse of anecdotes as evidence but out interest here is with this dimension.
Use and misuse
Is this laziness or an elevation of one’s own encounters in life? Perhaps, a bit of both. However, in certain areas, several anecdotes can be strung together to create a compelling story line, albeit (intentionally) misleading. The criminal justice system, especially based on the jury system, tends to rely heavily on anecdotal evidence to damn or liberate someone. In fact, a sometimes not so subtle use of such evidence is a clever ploy to influence the jury, in the knowledge that the judge advising them to disregard will have no real impact because the jurors’ minds have already absorbed it. Used this way, cited anecdotes become an effective channel to bring people’s biases to the fore to lead to the intended (decisive) views. The only way you can challenge such misuse is through another misuse where you put together contrarian anecdotes, which will bring to the fore either another set of biases or in some cases, the genuine portrayal.
There are certain theorems in mathematics which haven’t received a conclusive proof, logical proof not empirical verification. Every new instance that ‘proves’ the theorem is akin to anecdotal evidence but is so different from the general use of anecdotes. Anecdotes do play a role in the social sciences too but it is quite problematic because it relates to behavioural aspects, which are vulnerable to many influencers. In fact, there is the ever present risk of confirmation bias in social sciences as people tend to lean towards anecdotes that support their hypothesis. What we should bear in mind is that there can be anecdotes and anecdotes that may imply or indicate completely contradictory phenomena. It is only when anecdotes are domiciled within some regulative idea that they earn credibility. And therein lies the risk of misuse.
To be fair, a string of anecdotes veering around some stable behavior does call for a careful evaluation. However, it also calls for efforts to look for data that will lend credibility to the anecdotes and may lay the ground for a provisional statement or hypothesis. To use the language of statistics, the question is whether such anecdotes represent an appropriate sample for a population. To conclude what cannot be, extreme caution is advised in the use of anecdotes as misuse is more the norm than exception.
Takeaways
Widespread tendency to rely on anecdotes as evidence
Use of anecdotes is different in different disciplines
Biases decide which anecdotes are considered important
Anecdotes can be useful but caution is advised
