I went to a seminar he gave in All Souls College once, on communism, about fifteen years ago. I left liking the man very much - as dry as talc but with a warm wit that revealed itself in asides made whilst sipping black coffee - but also with a feeling of disappointment: I hadn't heard anything new or revelatory.
But then I realised I'd just been listening to a man whose ideas had triumphed so absolutely in his own lifetime that they'd become part of the intellectual air I was breathing. I don't think there have been many thinkers fortunate enough to experience such a rich justification.
Christopher Hitchens has written an appreciative assessment of him here. I wonder what Hitch, author of 'God Is Not Great', would say about Kolakowski's views on religion? The latter's philosophy was deeply rooted in an awareness of the importance of Christian thought. He believed that the more worthwhile ideas to have emerged from Europe in the last three hundred years or so were ones that retained some basis in a foundational Christian morality, the 'good' bits of sceptical and secular post-enlightenment thought included.
Kolakowski is very interesting - clear yet subtle - on the role of religious belief in the contemporary world, its relationship with enlightenment and modernity. A good way in is to read his 1990 book of essays 'Modernity on Endless Trial' (you can get a taster on Google books).
The essays are elegantly and clearly written, accessible. Their sceptical, doubting arguments resolve themselves into a sort of optimism: it's the intellectual tussle - engaged with humbly and ingenuously - that's the point. However, not without leaving you with a few observations along the way that are more than capable of making you pause. This one paragraph, from the title essay, also illustrates why the word 'mordant' is so often used about Kolakowski:
'I was told that near a Nazi extermination camp, where the soil was superbly fertilized with the ashes of uncountable cremated bodies of the victims, the cabbage grew so rapidly that it had no time to form a head and produced instead a stem with separate leaves; apparently it was not edible. This might serve as a parable for thinking about the morbid tempo of progress.'
UPDATE: The Times obit has come out today. It provides an excellent overview of his thought across the years. It's especially useful in summarising his thoughts on religion, which deserve greater exposure in the debate with Hitchens, Dawkins, et al.