It is curious how an idea eloquently expressed can be read about, absorbed and thoroughly understood and then, minutes later, be brought to mind again by means entirely different. Synchronicity? Something of the sort.

The principle was well illustrated for me last week when Craig Brown’s reasoned objection to writers talking about their work, which he expressed in the Mail on Sunday, was swiftly followed – as I moved from newspaper to novel – by Agatha Christie’s trenchant explanation of why she refused to do this.

Craig wrote: “At literary festivals, the pleasure of reading must take second place to the more dubious pleasure of hearing an author chatting. The process goes like this. An author spends years crafting the best book possible. The book is then published, and the author is invited to talk about it. Reading aloud is frowned upon: organisers and audiences alike prefer the loose, unformed, impromptu sound of talking.”

And what of Agatha Christie? Her view was made clear in the 1956 novel Dead Man’s Folly.

The opinion was given, of course, not in her own name, or even in the narrative voice, but by the character Ariadne Oliver.

This Christie ‘regular’ is herself a writer of detective stories and makes observations which can be taken to accord with the views of her creator.

On this occasion, Mrs Oliver is delighted to be distracted from a duty in hand by a phone call from Hercule Poirot. “It’s splendid that you’ve rung me up,” she tells him. “I was just going to give a talk on How I Write My Books. Now I can get my secretary to say I am unavoidably detained.”

She goes on: “I’d have made the most awful fool of myself. I mean, what can you say about how you write books. What I mean is, first you’ve got to think of something, and when you’ve thought of it you’ve got to force yourself to sit down and write it. That’s all.

“It would have taken me just three minutes to explain that and then the Talk would have ended and everyone would have been very fed up. I can’t imagine why everybody is always so keen for authors to talk about their writing. I should have thought it was an author’s business to write, not talk.”

This can certainly be seen to have applied to Dame Agatha, as she became, in her dealings with the good folk of Wallingford.

Though she lived among them from the late 1930s until her death in 1976, she could not be said to have been part of the community. She was not even on speaking terms with her next-door neighbour.

Her only public ‘duty’ there was to serve as president of the local amateur dramatic group, the Sinodun Players. Even in this capacity, she insisted there should be no need for her to do anything except attend their performances. She usually did, up till the end, sitting in the front row in a mink coat teamed incongruously with plimsolls (she had poorly feet).

Her contact with the local press was virtually nil. She relented just once from her no-interview rule to talk on the telephone wth my colleague Don Chapman.

This was principally (and commendably) because she wished to pay tribute to the staff of the Nuffield Orthopaedic Centre, in whose care she had recently been.

Throughout her three-week stay, she told Don, fans had kept writing to her, saying now she was in hospital and had to rest, they hoped she would write another thriller.

She said: “I don’t know whether you’ve ever been in bed with a broken hip. But I’m over 80, you know, and the last thing I felt like doing was settling down to some serious writing. All I wanted to do was to get home to Wallingford and my lovely garden.”

Her stand-offishness in respect of the townsfolk would seem to me to have been a reflection, in part, of her contemptuous dismissal of those she judged not to have been her social equals.

Dame Agatha would appear to have been on easy terms with academic Oxford, as she came to know it through her archaeologist husband Sir Max Mallowan. His All Souls colleague, the often waspish historian A.L. Rowse, held them in high regard.

He wrote in All Souls in My Time (1993): “Max and his wife Agatha Christie became dear friends of mine. I loved going out to lunch with them at Wallingford, where they now lie in the churchyard beneath the shadow of Cholsey Church Tower.”

A thick vein of snobbery runs through most of Christie’s work – and certainly through Dead Man’s Folly, set in a grand country house whose owner is peremptorily dismissed as a parvenu.

The book is far from being one of Dame Agatha’s best, with a daft plot and a denouement preposterous even by her standards.

The book set me one little poser, though. Christie writes at one point of “a plastic collar box”. Is this a box for plastic collars – a sartorial device favoured by the lazy, since they could be wiped clean – or a plastic box for collars of all types?

Alas, we shall never know.