Anecdotes vs. Evidence

We all know that a single anecdote is just that, a one-off observation or event.  Some generalize a single anecdote or couple of them as a rule.   We usually call it evidence supporting a rule and conclusion.  Lofty, right?  We all do it – often making an incorrect conclusion based on a semi-inductive argument  from grossly incomplete information.  

The question is this: Can a multiplicity of anecdotes constitute evidence?   And if so, how many do you need?  How sweeping need they be, and does their incidence correctly develop evidence?  The answer is really unknown, but it clearly is one of the operational aspects of social living.  It even applies to science.  What is done is that a model is created that fits the anecdotes.  This lends our treasure trove of anecdotes as actual and credible evidence.    This is another and rather pointed situation upon which humanity is socialized and is sustained.

There remains the question of how many anecdotes are required to make a rule or more generally a theory?  This is something akin to the “heep” paradox – but in reverse.   Suppose you place a single marble into an area, and keep adding more and more marbles.  Soon you have a bunch of marbles, still individually observable.  Add more and more.   Eventually you have a “heep” of marbles.  But when does the transition take place?  It seems to be, in this example, where individualization becomes impossible or unsupportable.   This applies, as well, to anecdotes.  When does their plurality make individual anecdotes unidentifiable?  We don’t know.