Towles' plot can be abbreviated into one sentence. A former Russian aristocrat, condemned after the Russian revolution to live in a Moscow hotel, stays there throughout collectivisation, purges, the Second World War and Stalin's death, acquiring friends, skills and love along the way. As one gentleman writing about another, Towles disdains any trite tics or tricks. A gun is fired, but only once, into a photograph. Sex scenes focus on the cosmology of freckles on a lover's back or that same woman's brusque instructions about closing the curtains post-coitus. Deaths occur decorously off-stage. Intrigues concern assembling the ingredients for a bouillabaisse or arrangement of the placement for a dinner. Moscow beyond the hotel is depicted only in a fretful, fleeting visit to a casualty ward and one brief, lighthearted stroll across Red Square. "The sky was the very blue that the cupolas of St Basil's had been painted for."

A plot so ostensibly thin is a prop for serious work. Towles defined a novel for me as "a machine for meaning". He elaborated by arguing that a story may well be entertaining, and certainly should affect the emotions, but the tale also needed to push the reader to think. All available devices in a writer's tool kit could be used: plot, character, imagery or poetry.

That range, Towles contended, explains why we still argue about Hamlet. The richness within its text is developed in a consistent and organic manner, one deep and dense enough to stimulate unending debate. Put differently, as John Donne would have noted about a novel set in a hotel, love combined with talent can "make one little room an everywhere". "Let sea discoverers to new worlds have gone; let maps to other, worlds on worlds have shown." Towles requires only Moscow's Hotel Metropol.

Thinking is notoriously hard work; too few take it on, and thinking for five minutes at a stretch can seem a long time. To write a truly thoughtful novel, respect is critical - respect for the reader, respect for what a novel can and might try to do, respect for intelligence and irony. Constructing a machine for meaning demands such respect.

Towles recognises that he asks a lot of any reader. He works on the basis that readers do not want that much explained to them. Cutting, which means focusing on rigorous economy and insisting on a consistent tone, can tug out of a narrative those layers of explication which otherwise bog it down. In Towles' opinion, readers are a good deal smarter than publishers think. They are interested in "climbing the mountain" of a serious book.

Towles reckons that the reader wants to be set to work, to be pushed into keeping up. Much of A Gentleman in Moscow goes one step farther, obliging the reader to catch up, even in nominating famous quartets or considering if Russians would burn Moscow a second time. Towles described A Gentleman in Moscow as a hybrid, a book hearkening back to the great aspects of novel writing while adding a lighter, modern touch.

Shorter chapters, more elliptical sentences, scenes which conclude without a clear meaning, jumps in the time sequence, all these contemporary add-ons are integrated within a wonderful story. However smart a reader may be, she still ends up out-smarted. The subterfuges with which the gentleman in Moscow outwits secret police, quislings and commissars pale by comparison with the games Towles plays with the reader.

Towles thinks (and has two million proofs) that his work responds to a natural desire for complexity and depth and nuance and ambiguity, a desire not whittled down by social media. For Towles, readers are disheartened by twitter and the 24-hour news cycle. They then turn to long-form television narratives, stories which take a dozen hours or more to tell. Those tales rely less on suspense and surprise than they do on ambiguities and character changes. Much briefer feature films now do the opposite; their formulas entail "people doing and saying the same things" over and again.

As for books, rather than blood and bullets, the cover of A Gentleman in Moscow depicts wistfulness. A stout man, wearing a hat indoors, hands clasped behind his back, peers out a window. Wistfulness and whimsy are first cousins to irony. Irony, in turn, is the last refuge of a gentleman - in Moscow as elsewhere. Alone among Russian literary heroes (except perhaps for Tolstoy's Stiva Oblonsky), Towles' Count gives irony and charm a good name once more. He lives as both outsider and insider, confined within his hotel but standing outside the otherwise all-enveloping Stalinist system. The "former person" becomes current again, in a delightfully quizzical, quixotic way. Unlike generations of English characters from upstairs and downstairs, the Count's charm is a happy, vital quality, devoid of snobbery or fussiness.

Towles put that point more gracefully. He suggested to me that irony - like surprise, sharp dialogue or suspense - could supply the electricity required to lift a story. By virtue of his choices and circumstances, Towles noted, the Count grows and becomes more practical. In my view, he does more again. Russian novels abound in odd types.

The melancholy list includes the awkwardly remorseful (Raskolnikov), the malevolently vengeful (Karamazov, Fyodor that is), the wilfully slothful (Oblomov) , the frivolously hurtful (Vronsky) and the ineffectually genteel (the older Kirsanov). Towles' Russian, created by an American, now adds new electricity to that mix. The spark is generated by intelligence, wit and grace, as it is with Anton Chekhov.

Where, then, does A Gentleman in Moscow come from? The same question might be asked of other idiosyncratically charming modern novels, of The Siege of Krishnapur (Ireland: JG Farrell), The Sunset Club (India: Khushwant Singh), The Architect's Apprentice (Turkey: Elif Shafak), An Imaginary Life (Australia: David Malouf), or To Love a Woman (Israel: Amos Oz). With Amor Towles, though, the answer is quite particular.

Towles spent 21 years as an investment manager at the same Manhattan firm. When I asked him whether that experience taught him lessons useful for writing (like shrewd perception, say, or deep analysis), Towles scoffed. He thought that his work had instead taken away a decade and a half when he might have been writing novels.

Nonetheless, Towles did note that, when he began to write professionally, he did not need to worry about external pressures. Money was not an issue. He did not bother about impressing his parents or how his friends perceived him. "My sense of what I was was not really at risk."

That said, the transition is unusual. Publishers, lawyers and politicians often have a go at a novel; those in the finance industry, less so.

Towles is also distinctive in his emphasis on designing his books (for up to a year), then ensuring - "the biggest challenge" - that the tone is right, consistent, and holds the interest of a reader. Tone is a word borrowed from music, befitting a lover of both jazz and rock and roll.

Tone here sets pitch, harmony and melody in the Count's concerto. They work wonderfully well.