One idea, one word, one strand, pulls together three big stories in the news this week. It runs right through revelations of cheating by broadcasters. It is stitched into anxieties about the integrity of the honours system, anxieties hardly banished by the Crown Prosecution Service’s disinclination to bring charges. And it threads through the doubts and hesitations about David Cameron’s renewal of the Conservative Party, tracing out a question that the Tory leader needs to start answering after his party’s failure to break through in Thursday’s two parliamentary by-elections.

That word is “authenticity”. Our age is approaching a crisis of authenticity. Pontius Pilate’s “What is truth?” has wrongly been represented as meant contemptuously. But was meant despairingly. And Pilate did not have to contend with television editing, with Photoshop airbrushing, with political grooming and message-tailoring, or with honour as an impulse purchase.

Like plants whose presence marks the vein of a particular mineral in the soil beneath, a clutch of fashionable words and phrases alerts us to a lurking, growing problem with authenticity. They are all words about presentation and perception. They come from the worlds of marketing, of fame and of entertainment. They include “virtual”, “brand” and “rebranding”; “message”, “narrative”, “signpost” and “beacon”; “reputation-management”, “profile”, “target”; and (of course) “story”.

Each of them in its way offers the same hint: that appearance is the new reality; that what a thing is, is becoming secondary to how a thing seems. A book by Neal Gabler – Life the Movie: How Entertainment Conquered Reality – diagnoses the warping of perception in the world of celebrity. Here I want to look at way a similar lie warps politics and the media.

Understand that the lie is sophisticated. If the Devil came among us in the shape of a marketing consultant, he would not say to his client: “The product doesn’t matter”. He would say: “Of course the product matters hugely; but however good the product, the first thing to get right is how your potential customer sees it before deciding whether to buy – or how he feels about what he’s bought.”

And if Beelzebub took the shape of an honours salesman he would not say: “Give me half a million. You’ll be a pretty fake sort of a Lord, but the world will never know.” He would say: “You and I both know you have so much to offer public life; your investment in the Labour Party is a sign of your public spiritedness; but our poisonous press might misconstrue; so may we find a way to keep this discreet? By what might seem deception, the essential verity of your fitness to be a lord is protected.”

And were Satan to take the shape of Tory Central Office and approach the Ealing Southall Conservative Association, he would not say: “Tell your local would-be parliamentary candidates to get stuffed; we want a candidate who can make a big splash fast, regardless of his record of commitment to our party.” He would say: “Surely the first thing to do is win; otherwise, sadly, the calibre of the candidate is immaterial. And there’s a wider message we want to send out about inclusiveness, youth and picking winners. We know a fellow who ticks these boxes. His victory would be a beacon, helping change voter perceptions nationwide.”

Were the Evil One, finally, to do a stint as a television producer, the last thing he’d instruct his production team to do would be to fake it because who cares if TV is truthful. He would say: “The truth is everything to me, but it’s truth at the deepest level we need to pursue. The truth about children in need, about public generosity. And truth – yes – about entertainment, which our viewers know is the deal, and what they switch on for. They know where we’re coming from, that a quiz is just a game; and they want it to be slick and watchable.

“OK, a handful of viewers who tried to take part may have been ‘fooled’,”(and here the Devil crooks two fingers of each raised hand in the quote-marks gesture) – “but 99.9 per cent of our viewers wanted to watch, not play: to be entertained and heart-warmed in a good cause. Our show did what it said on the tin: entertained them in a good cause.”

Slipping away from BBC Television Centre, Satan might nip back to Tory HQ to advise the new leader on how best to make the change, be the change. And what he most assuredly does not say is: “Here’s a nifty stunt: fly to Rwanda and make like you’re doing NGO stuff with some starving Africans. Voters will think you care, ha-ha.”

He says: “Look, David, you do care. But you need to show it or you’ll never be prime minister and put your principles into action. We both know – and for Pete’s sake, the voters know – that a few days in Rwanda surrounded by cameras can’t achieve useful fieldwork; but your visit works on deeper levels. It’s a metaphor, David. It says ‘I care’; it says ‘Tories care’; it says ‘the issue matters’. It says ‘The Conservative Party has changed’. It’s the narrative, David, and the moral of the story is true, even if the story itself is a bit . . . er, constructed.

“So this is fieldwork, Captain, but not as Rwandans know it: fieldwork of a more cosmic kind. Its truth is timeless. And if it gets you to Downing Street it helps more kids than you and a food parcel could ever reach.” And as the Devil slips back into BBC Television Centre to advise that since a documentary is meant to get across the “essential” truth about homelessness, some of the sequences may need to be tweaked and the programme producer’s PA may just have to pretend to be a down-and-out, we tiptoe away. The last thing we hear the Devil explain is that the truth itself is often banal, incoherent, misleading; whereas what he likes to call, not “truth” but “truthiness”, may have an essential honesty that mere, plodding veracity can never capture.

Block your ears to all that. I have to believe, because I want to believe in life itself, that the simple truth matters and that where it is not the foundation the building will fall. The website ConservativeHome is a dubious friend to David Cameron, but its Editor’s Diary advice to him this week after the Ealing Southall result – that it’s all about authenticity – is spot-on. We respect the Lords less because we know that despite appearances there are real peers and fake peers, and all peers ought to worry about that. I never trust what I see on TV because I know how TV is made. I am not alone.

I would suggest to the BBC, to the House of Lords Appointments Committee and to David Cameron’s Conservative campaign, three key and neglected priorities for our age: authenticity, authenticity, authenticity. Except, of course, that to make it a marketing slogan would rob it of the very thing it claims.

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