Are you sure?

I think I always know when I have not understood something. For example, I went to a symposium last year where one of the lecturers left me wondering what on earth his talk had all been about. Pinning him down afterwards it was evident that he was vastly knowledgeable in his topic, and in conversation was well able to deal with the questions I raised clearly, and very fully. But when he came to put a lot of his knowledge together to deliver in an hour's lecture to a group of people, the clarity with which he spoke disappeared, and I knew I had not understood what he was saying, in common, I suspect, with quite a few others.

But the obverse is not equally true. When I have partially understood, or misunderstood, I am probably confident that I have got the message, when in fact I have only got a bit of it, or got the whole thing totally wrong. But I don't know that. The greatest chance of being wrong is when you think you've got it right.

One of the joys of my retirement has been discovering the wonderful podcasts at www.historyofphilosophy.net where Peter Adamson's lucid delivery leaves me feeling I have learned something every time. Probably I have, but the question remains “how much of what was contained in the podcast have I grasped, and how accurately?” I follow up on some of the recommended reading and I have become gripped by the Stoics, with whom share an interest – the Art of Living, it has been called, and from whom I have learned a lot. I've even been stimulated to refresh my Greek. But even if I have grasped some of what the Stoic writers and modern commentators are saying, I know there is a lot more – well that's progress: realising that there is a (not too distant) boundary to knowledge beyond which lies an infinity of ignorance is in itself a good thing.

Among my growing collection of downloaded podcasts is a much larger one, not part of the main series, Podcast Live, a lecture delivered last year as part of the Arts & Humanities Festival at Kings College, London by Peter Adamson. He called it “A Brief History of Nothing”, the Nothing in question being the concept of Void or Emptiness which is prominent in the work of ancient philosophers. I have lost count of the number of times I have listened to it again. I do tend, it has to be admitted, to listen with my headphones on while lying in bed, and once or twice I have dropped off part way through. This is due to the lateness of the hour and the greatness of my comfort, not the lecturer's style. Now I think I have mined it fully, but even so, I find that I have to go and listen again to the podcast on Plato's Timeus, which has not lodged properly in my head.

Heavens, I'm 68 years old, nearly. I need more time to read, and to think more. It was Plato who first explored the important distinction between belief (of which an important sub-category is true belief) and knowledge. And still we haven't got it right. Just recently there was an item on the BBC about those experts one hears making predictions about the future of economics, sport, art, the weather, you name it. Well, one thing is for certain, about the future we have no knowledge. A study of these expert predictions revealed that the most compelling listening, most favoured by the public, is strongly associated with the confidence of the speaker. And the more confident the speaker the more likely he was to be wrong! Those experts who hedged their remarks with such phrases as “we can't be certain” and “there are several unknown factors” and “I don't want to be definite” and “all in all it seems to me that the greatest probability is...” were the ones hardest to listen too, and the least regarded by the public, and the most likely to be right.

It seems to me that we have a similar problem with the present, and sweeping assertions are highly likely to be wrong. When we are right, as my hero Karl Popper said, we are so by accident, and we can never be sure that we are right.

But even if I cannot be sure that I have properly and fully understood Peter Adamson's podcasts, the boundary of ignorance has been pushed a little further back and understanding has increased and most important of all, I may have made a slight improvement in the art of living.