A biography of the great art historian, Kenneth Clark, has just been published. It is reviewed in the Times Literary Supprumlement this week. And a paragraph in the review reminds us of something that might be forgotten in the commemoration currently going on around the world of an event 500 years ago.

Clark is mainly remembered now for his masterly book and BBC Television series, Civilization, first broadcast back in the 1960s.

Susan Owens, reviewing James Stourton’s new biography, notes that he has been able to quote extensively from Clark’s letters for the first time, “and the voice we hear is unexpectedly funny and candid.

“But it is the accounts of Clark’s involuntary reactions that perhaps shed the most light on the character of someone so often described as ‘chilly’ and ‘remote’. While making episode six of Civilisation, ‘Protest and Communication’, he kept breaking down in tears in front of an astonished crew as he stood at the church door in Wittenberg to speak Luther’s words ‘Here I stand!’ The shot took six takes.”

In the very depths of his being Clark felt the pain of the devastating impact on western civilisation symbolised by that moment in history, a gesture of rebellion – without passing judgement on its causes – from which flowed so much death and destruction, wars, persecution and impoverishment of the human spirit, century after century ever since.

James Stourton, KENNETH CLARK Life, art and civilisation, 496pp. William Collins. £30. ISBN 978 0 00 749341 8