Sometimes we need to re-evaluate tenets and beliefs that we may have held for years. And it is often serendipity that triggers that re-evaluation. One example of this occurred while listening to radio 4 late at night a few weeks ago.
The programme Think with Pinker was broadcast on 3rd February 2022 and is available on Apple Podcasts. If you are a “supporter” or intrigued by critical thinking, this is well worth a listen. Julia Galef and David Willingham are participants in the discussion.
The provocation Pinker gives us is “Why getting it right might mean admitting you’re wrong”. And the programme explores this and many related concepts and fallacies.
Most of what I learned or initially absorbed about rhetoric and the art of spoken word message design came from my mentor William Macnair during the late 1990s and early 2000s. The ideas he put over were compelling and always backed up with evidence. One of these he called the “Rule of Best Evidence” drawn from general and criminal law.
He, and then I, used this to demonstrate why, in convincing someone of an idea, only one piece of evidence was necessary and sufficient. Offering more than one piece of evidence (examples, data, quotations, credentials etc) would be self-defeating. I am fully aware that the Rule of Best Evidence is more properly associated with the hierarchy of evidence – for example an original vs a copy. But it seemed to me to be a helpful concept to which I signed up.
It was self-evident to me that people in my primary market – technology and consultancy – tended to over-explain, to provide multiple reasons for why their idea or assertion was correct. But the more they offered, the less credible they became. So the “Rule of Best Evidence” became part of the Kipper® methodology which I have taught – use only one piece of evidence in support of an idea.
A little epiphany
I still hold to this general principle of “less is more” but something that was touched on in the radio programme swiftly gave an insight into how people can react to and be really persuaded by evidence.
The observation made in the programme was that if you explain an idea with one example it might, but might not always, be convincing. But if you provided 2 examples, it would force people to think about what the two have in common – “how are both illustrations of the principle being put forward?”. This is what might create both belief and, importantly, memory. It follows that the two pieces of evidence must be of different types – it could be a survey statistic matched with a credential. It could be a return on investment alongside a staff survey.
So, I have re-evaluated that tenet held for 20 years and tweaked it – along with the advice I would now give to my clients. By the way, I still believe that credentials (e.g. “we have done this with a major retailer”) are the least persuasive types of evidence. And I also still believe that over-egging evidence – using many pieces – is counterproductive.
But I now would encourage the selection of up to 2 types of evidence to support any proposition or idea.
The other pay-off
The other benefit of this thinking is to do with behavioural types and styles that may be present in your audience. It is always a challenge if your target audience consists of both rational thinkers and those more persuaded through feelings and intuition. The “double evidence” approach will allow you to have two pieces and different types of evidence for each idea in your argument – therefore potentially satisfying the needs of these two distinct personal styles.
So, thank you serendipity and thank you Steven Pinker. You have caused me to check my own evidence and as a result I have changed my perspective. Getting it right has meant admitting I was wrong.