Tom Murphy tells a story about two old men, idling in a park in Paris. A pretty young lass passes by, and the old men look wistfully after her.
"Oh, to be 70 again," one says.
Murphy will be 80 next year. He looks at least a decade younger, and two decades tougher. But his voice has slowed (he apologises for it, needlessly) and his writing hand is afflicted by a tremor.
"If you have three clear days," he says, "I'll tell you what I have physically and mentally wrong." He says it in good humour, another joke about ageing. But then I ask about his work.
"This tremor in my hand," he says, and he doesn't finish. There is almost a flash of anger but he catches it.
Earlier this year, he picked up the Greek tragedy Agamemnon, by Aeschylus, which itself inspired Hamlet, his favourite play. He started work on something inspired by it.
"I was excited, almost passionate." He showed six or seven pages to a friend. "It's as good as anything you've ever written," the friend said.
But the tremor got in the way. "Maybe I will get back to it," he says, stoically.
He won't consider using gadgetry such as voice recognition software. The extent of his technological mastery, he says, is the fridge.
As age haunts our conversation, so too do his parents, each the inspiration, in different ways, for two plays currently being staged by Druid (details below).
Bailegangaire, first staged 30 years ago with Siobhán McKenna in the lead, was initially inspired by a photo of his maternal grandmother, Granny Shaughnessy (he takes it down from the mantelpiece; "formidable" is the only word).
This gave him the thought of writing a story for his children "so that they will know where they come from." But as he wrote, the play took hold. Soon: "Forget it, children."
The play depicts a bed-ridden old woman, Mommo, who barely recognises the two granddaughters that care for her. "My mother had Alzheimer's," he says, simply. "I witnessed it."
Now, he has written a companion piece, Brigit, telling of the early lives of Mommo and her husband, a carpenter, who is asked to carve a statue of St Brigid for the local convent.
"I've been thinking about my father a lot in recent years," he says. "He was a man in my family taken for granted. This is pretty personal stuff but at my age I don't care what you do with it. I was seven or eight when he emigrated. I think my mother was happier without him.
"He saved the family. The wire came fortnightly. He was a good man and I love him dearly" - he pauses - "now."
His father returned every year, and brought with him a muslin bag tied with string, full of threepenny bits. "Swag! I always expected that of him."
Later, he realised: "Every time he came across a thrupenny bit, he was thinking of me… That's love."
His father was an untrained carpenter, who hadn't served his apprenticeship and had left school young; but Murphy reckons he was an artist. As he grew old, his son encouraged him to retire.
The father moved home in July 1961, and the son left home six months later. Six months again, and he got a call to say his father was dead.
When he got home, there was a neighbour standing outside the house. "Sorry for your trouble," he said. And then: "You killed him, you know."
"I'm trying to redress…" Murphy says, and tails off. "I now realise that (my mother) was claiming me from her husband."
Brigit is a more simple, gentle play than many of his others. But the children in it will grow up to become the thwarted women caring for Mommo in Bailegangaire. Knowing this gives it a bleak aspect. Is this intentional?
"The vale of tears," he says. "I celebrate the heroism of humanity."
And then he quotes Camus: "There is only one really serious philosophical question, and that is suicide.
"Perhaps that answers your question," he says, but there is a twinkle in his eye.
I think Murphy's plays help us all know where we come from: a portrait of the Irish psyche, if such a thing exists. But he disavows this. "I'm not a sociologist," he says.
"I seem to have absorbed life rather than observed life. I think the self is the deepest well."
Bailegangaire and Brigit play at the Town Hall in Galway this weekend. Bailegangaire plays in Clifden on Tuesday and Wednesday.
Both plays are at the Olympia as part of the Dublin Theatre Festival, October 1 to 5. See www.druid.ie.