THE world has entered a new dark age, where uncertainty and ‘fake news’ have ushered in an ‘Un-Enlightenment’, according to former BBC journalist Gavin Esler.

He will discuss the issue when he delivers the 2017 Magnusson Lecture at the forthcoming Wigtown Book Festival, which begins this weekend in Dumfries and Galloway.

Esler, who no longer works full-time at the corporation, said one of the key dangers facing society is the lack of trust and belief in experts, in government, and in one of the cornerstones of Enlightenment thought: verifiable facts.

He will say that this ‘Trust Gap’ has opened the door to figures who tell good stories but are not necessarily tethered to objective truth, such as President Donald Trump, and others.

Esler, who is considering writing a book on the subject, said the time has come to find a way to fight back and defend rational and facts-based issues, but not to fall into the trap of “being patronising and saying everyone who voted for Brexit or Trump is stupid”.

He said: “We live in an Age of Uncertainty.

“Enlightenment values have been undermined and we have entered an Un-Enlightenment in which the general public has lost trust in governments, leaders, the media and even in the idea of facts, knowledge and expertise.

“The rise of populist leaders and movements from Trumpism and the alt-right to Brexit to Syriza, even to President (Rodrigo) Duterte in the Philippines, is in part due to the ability of populists to connect through simple story-telling with the mass population.

“This lecture is a call to arms for those of us who value facts, science, knowledge and expertise.”

He added: “We must make the case for those values, connect with the mass population, challenge and defeat those who pretend that ‘Alternative Facts’ are anything more than falsehoods.

“If we do not close the Trust Gap then the Un-Enlightenment will triumph.”

The annual lecture at the popular festival is sponsored by the Open University, and is a centrepiece of the Wigtown Book Festival.

He added: “Talking about the Enlightenment in Scotland of course has a very big resonance.”

Esler said that Trump succeeded because he built his own story, whether it was true or not.

He said: “We have looked in the past to trusted guides, to those who tell a good story.

“There is nothing new in this idea – Moses did it, it is a great story, the Ten Commandments.

“Now I am not comparing Moses to Trump, but Trump did tell a story, and the appeal of Trump and Brexit is that such as that despite all the expertise against them, they succeeded.”

The lecture is titled How Stories Built Trust and will be delivered on September 23, and is the festival’s speech to commemorate the life and reflect the interests of the academic and broadcaster Magnus Magnusson.

Esler is an award winning journalist and was a frequent broadcaster on the BBC - his report on the military build-up in the Aleutian Islands as part of the Reagan administration’s New Maritime Strategy earned him a Royal Television Society Award.

In 2007 Esler won a Sony Gold Award for his radio documentary report Letters From Guantanamo on Sami al-Hajj, one of the detainees in Guantanamo Bay. Following the broadcast al-Hajj was released from American custody.

Adrian Turpin, the festival’s artistic director, said: “Gavin Esler has interviewed many of the most powerful leaders of our time.

“His dedication to facts, realities and truths have made him a trusted witness to major events that have shaped our world.

“We are proud that he is using the 2017 Magnusson Lecture to call for a defence of reason against the powerful forces that are on the rise round the world which seek to use fear and prejudice to undermine progress, science and rationality.”

Esler will also be chairing a book festival event entitled The End of American Influence? This takes place on Sunday 24 September.

Wigtown Book Festival takes place from September 22 to October 1.

Esler was a main presenter on BBC Two’s flagship political analysis programme, Newsnight, from January 2002 until January 2014, and presenter of BBC News at Five on the BBC News Channel more recently.

He is the Chancellor of the University of Kent.

His family lived in Clydebank before they moved to Edinburgh.

He began his education at Duddingston Primary School in Edinburgh, before gaining a scholarship to George Heriot’s School at the age of seven. He studied at the University of Kent, graduating with a BA in English and American literature in 1974.

Until 2017, Esler was the main presenter of Dateline London on BBC News and BBC World News.