The writer shuffles towards the bar, throwing off the chill of the evening with a shrug and warming himself with the anticipation of a hauf.

A voice mutters somewhere to his left: "It was Glasgow on a Friday night, the city of the stare." William McIlvanney smiles. It is his duty. The opening lines of his second Jack Laidlaw novel have just been recited by an innocent bystander. Laidlaw, laid delicately but not irrevocably to rest in Strange Loyalties more than two decades ago, has again been brought to life amid the fumes of a pub.

It is further, unnecessary evidence that McIlvanney is pursued by the figures of Laidlaw, a troubled intellectual – is there any other kind? – and members of an Ayrshire mining family called Docherty. He may succumb to the chase. Laidlaw was the hero of three groundbreaking McIlvanney novels and the Dochertys featured in two works, Docherty and The Kiln, that articulate brilliantly what may be called modern Scottish history.

McIlvanney accepts these characters speak to his past, but he may be compelled to give them a voice in the future. Sitting in the basement dining area of a Glasgow Italian restaurant, he suggests: "I have a few ideas for Laidlaw and for a third Docherty. I would not advise anyone to hold their breath but these are vestigial thoughts I may take further." The casual softness of the words cannot detract from their import. A comeback for Laidlaw or Tom Docherty, grandson of the original in the eponymous novel, would make the Lazarus business look routine.

McIlvanney is fit for the task of resurrection. He uses a walking stick to accommodate a back condition as he makes his way towards the table but, at 76, he retains an eerily youthful aspect in appearance and vigour. The next case for Laidlaw might be to divine McIlvanney's secret of youth. The answer may be found in a picture in the attic.

The stares in the restaurant and the words in the pub testify to McIlvanney's enduring place as a beloved Glasgow author. Now living in the city's south side, the boy from Kilmarnock grew to be the philosopher of these mean streets, and should Jack Laidlaw and Tom Docherty once again take up their woes and walk, there will be a congregation of jubilant believers.

Something has been sparked in the writer as Canongate prepares to publish his body of work after years of neglect. McIlvanney now talks of a website that will collect his journalism and of further expeditions for his intriguing policeman and for the Docherty clan.

It does not require a detective to divine that both Laidlaw and Docherty take something from their creator. "Laidlaw allowed me to say something to a wider audience," he says. "He has an abrasive voice but he is dealing with hard things. You are saying things about real people in a real city. If it has a philosophy, it is about surviving with dignity and decency in the main."

Be assured, it has a philosophy. McIlvanney heads off discussion of the crime genre with an admission: "I do not read thrillers." Thriller writers, of course, read him. He was the standard-bearer of tartan noir and has had an enduring influence on American crime-writing. The genre gave him room to manoeuvre and he used it. The crime is detailed in the first pages of Laidlaw, the murderer named on page 23.

"It is not a whodunnit but maybe a why did he do it," says McIlvanney. "Laidlaw gave me the chance to say things about society. I sort of held him up as a mirror to what was going on. He was a good man dealing with bad things. He gave me the capacity to approach what I wanted to write about from another angle. He could come in the back door in a way."

He adds: "My reading is mostly re-reading. I am not one for contemporary novels. I do not have a deliberate pursuit of the modern. I read Montaigne's essays, Proust and Shakespeare - possibly because he is the best in the business."

There is no apology or bombast in any of this. It is just a matter of fact. Laidlaw would approve. In The Papers Of Tony Veitch, the character reflects: "The only climate is the truth." The police officer also has words of censure against academics who "use literature as an insulation against life rather than an intensification of it". This is a detective who keeps the statutory bottle of whisky in a bottom drawer, but only under a tome of Kierkegaard. Laidlaw is a rebuke against the triteness of moral certainty, an evangelist of the sanctity of doubt and a preacher on the necessity of love. Laidlaw is the product of a tough but inspirational life but so is William McIlvanney.

"Mammies is great"

Jack Laidlaw, The Papers Of Tony Veitch

The writer pauses and a smile that demands to be described as rueful passes across his face. "There are times in life when I could be said to have made an arse of it. My mother would then say, 'That's not what you do, son.'" The shuddering impact of that deceptively gentle rebuke causes him to shake his head.

The character of McIlvanney was formed in an extraordinary childhood and his mother was crucial to his development in word and deed, in example and in determination. Helen McIlvanney left school at 12 to work in a mill, woefully robbed of a formal education. She became a wife to a miner, Conn, and the mother of four children: Betty, Neil, Hugh and William. She was also a serene presence in a turbulent household. "We argued all the time and about anything. Politics, films, books. There was always an argument and you learned it was always worthwhile making your point." Laidlaw describes such discussions as a way of getting to know oneself and Mclvanney does not disagree.

There were quiet moments. The writer remembers coming home from the dancing to find his mother sitting up, waiting for him with a copy of The Rubaiyat Of Omar Khayyam in hand. There is nothing overly sentimental in this reminiscence, just an acceptance of living in a house where books were to be devoured in between arguments. Helen McIlvanney, too, made an intervention that changed the course of her youngest child's life. "There are great moments that seem casual at the time but become definitive," says McIlvanney. "There was one when I was 14 or 15 and I was in the lobby and I heard my mother and father talking. You know that way there is a recognition, you say to yourself, 'They are talking about me.'

"My father was saying, 'Willie should leave school, get a job and bring money into the house.' I heard my mother saying: 'Do not even dream about it.' My father just murmured: 'Aye, all right.' Now, that was important. Because I would not have minded going out to work. I would have said: 'Why no'?'"

Of course, his elder brother, Hugh, became a peerless sports journalist and author without a university education so surely William would have written too without a further, formal education? "I think so. I was writing poems at 14 and showing them to [elder brother] Neil because he was the one in the family who would have given me the kindest words," he says with a smile.

"But in more ways than one my mother was the key. In my first month at uni my father died and my mother went back to work in a mill to help put me through it. She was 49. Later, I gave her money when I was earning for I do not know how long. Then one day she said, 'That's it, Willie, no more money.' But at least I gave her something for a wee while."

There was another gift. "I wrote her a poem as a sort of thanks, I suppose, maybe more precisely a celebration of her life. Liam and Siobhan [his son and daughter] also wrote her letters or sent her postcards from their travels. I learned later from one of her friends that my mother would take out the poem and these letters and read them every night in her bed before going to sleep." She was 95 when she died.

The woman starved of formal education was a matriarch of a line of learning. McIlvanney graduated from Glasgow University and Liam, an academic in New Zealand, and Siobhan, who lectures in languages, earned doctorates at Oxford. McIlvanney, too, became a teacher of English. "I went into teaching without any missionary zeal," he says "It was about paying back for the education I got. I said I would do it for a couple of years and the world kind of lost my address. It did not beat a path to my door but what simultaneously happened was I discovered I loved teaching." He taught for 17 years. "When I packed up, I thought I had paid my dues," he says.

"When you lose touch with the front line, you're dead"

Jack Laidlaw, Laidlaw

The writer pauses to put a dash of water in his whisky. It is almost time to move on. With the referendum on Scottish independence only a year or so away, a nation, too, is wiping its feet on the door of an uncertain future. "I was outspoken in my support for the parliament and I am glad I did that," he says, recalling his prominent involvement in the 1999 home rule campaign. "My inclination is to vote yes next year, but I do not think we know enough. I would want more precise details on separation. One of my reasons for wanting a parliament is that Scotland voted Labour for generations but still got a Tory government. I want the socialist dimension of this country to have more power but there isn't a Labour Party any more."

He is dismayed by the politics of Britain. When asked about his political heroes, he replies, "They would not be very contemporary, that's for sure. Keir Hardie, for certain. But now we have a sort of paramedic politics and paramedics cannot cure a cancer. The NHS, along with the emancipation of women, was one of the greatest acts of the 20th century yet there is now a process to dismantle it. Politics should give a serious view of how to save a society, how to cure its ills. It seems to me that all politicians can offer today is an Elastoplast."

He is not downcast, rather quietly defiant. He defends the state of the nation. "In Scotland there survives some amount of mutual concern which I think is the key to a healthy society. There is also a refusal to be dazzled by money and status.

"I believe in people. My heroes are the people and I still believe the sort of values that I talk about in Docherty survive, maybe in a piecemeal way."

These involve a compassion that understands and celebrates the inter-dependence of people while emphasising the need for the individual to discover then walk a true path.

McIlvanney is poised at a junction. Will he stride down the mean streets with Laidlaw once again? The detective made his first appearance in 1977; The Papers Of Tony Veitch followed six years later and the trilogy was completed with Strange Loyalties in 1991. Or will Tom Docherty, grandson of Tam of Docherty and hero of The Kiln (1996), be a better route for what McIlvanney wants to say about society?

Famously, McIlvanney was urged to bring out a Laidlaw every year with promises of riches. He chose the road less travelled. "I had other things to do. I did not want to be defined by Laidlaw. I never wanted to write to demand," he says.

Any regrets? "No," he replies immediately. "I might not have written The Kiln, of which I am quite proud. In any case, I have always written from compulsion. I cannot even write to my own order, never mind anyone else's."

He has been accused of what some see as the sparseness of his output since Remedy Is None was published in 1967. "Nine novels and a book of short stories. It's not bad," he says. The criticism, of course, is absurd, clumsily applying the imperatives of industrial output to the mystery of creation.

"It might be laziness, but I don't think so," he says. ''I taught, I did some journalism, I did a bit of TV." This banishes the heretical thought that a dilettante could be conceived in Kilmarnock.

"The ideas about going back to Laidlaw are in an early stage. I am liable to go walkabout." This is a reference to his propensity to write what he must rather than what publishers say he should. "I never like to talk about ideas before they are fully formed. A third Docherty book with Tom Docherty would be interesting. I would set that in Glasgow. I love the city with the zeal of a convert."

There is a spark that is needed to detonate any further creative explosion. "I need the compulsion. It is about following that demon. I think if I had written other Laidlaws just because the market wanted them I would have lost the sense of my own commitment and I would have been defined by commercial demands. I would not have liked that. I don't like that."

There is no ferocious protest in any of this, just a measured, sober assessment of the way he works. There is no harsh judgment either. McIlvanney may have entered the age of self-acceptance but he has retained a quiet optimism all the more admirable because it does not shirk the cold wind of reality.

He once had Laidlaw meditating thus: "It was about hope - about trying to begin again because he had no option." McIlvanney awaits the tyranny of compulsion that may find him arm in arm with Jack Laidlaw or Tom Docherty striding down a path not yet cleared, not yet defined.

But first, he drains his whisky, gives thanks for dinner, takes his stick and strides to the door of the basement restaurant. It opens on to a landing 15 feet below Laidlaw's beat. He turns and faces the steps. It was Glasgow on a Tuesday night, the city of the stair - n

Aye Write! is celebrating the relaunch of William McIlvanney's novels on April 20 at 7.30pm. For tickets, priced £8, visit ayewrite.com or call 0141 353 8000. Laidlaw is published by Canongate on May 2. Other novels will follow this year and in 2014.