This week, Mark Thompson, former Director General of the BBC, gave a series of three lectures as part of his Humanitas Visiting Professorship in Rhetoric and the Art of Public Persuasion, in honour of Philip Gould. These lectures were all centred around the theme of how the language and tone of public debate has changed in recent years in ways that have been detrimental to the cause of public understanding and has created a ‘cloud of unknowing’ within the wider public regarding matters of civic policy.