In July BBC Radio 4 announced the result of its poll of listeners to find the “the greatest philosopher of our time”. And the winner was – Karl Marx, as the first past the post with 28 percent of the 34,000 or so votes cast, way ahead of the second, the 18^th century Scottish sceptic and agnostic, David Hume, with 13 percent, and the early 20^th century logical-positivist, Ludwig Wittgenstein, with 7 percent.