Peters thinks the experience of age is undervalued in New Zealand politics with its obsession with culling the "dead wood" and bringing in younger, fresher faces.
"We've had people put into the job as Prime Minister who have learnt on the job and learnt very little." He won't say if that is directed at Mr Key.
It is true he still has the stamina of an ox. He puts that down to genes and early training.
In his childhood on a farm he says: "It was up in the morning early and go to bed late. That was a form of training for politics. You've got to train for it."
Peters is actually pondering a life beyond Parliament. He refuses to call it "retiring", saying he would never retire "from an active life".
However, he does see himself with a post-politics life. He says he will do the things he likes to do. "Fixing up boats, mucking around with horses, going boating, fishing. Projects that have a start and end to them."
He has stuff to do before them, but insists it won't be seeking out "positions and honours" for personal glory. "Whatever my enemies think, that's never been my career."
He may even have a book in him. Tonight he won't be doing anything self-indulgent like having a party. He says he doesn't have time. As a child, he did not have parties either.
"When you come from a family of 11 children it becomes less a matter of celebration. You'd be having one a month. Big families don't, small families do."
He did sometimes get a present. His worst was a Japanese tin car. "I wound it up, it went across the room and the spring broke."
He has bought Japanese cars since then. "Well, you've got to move on, don't you?" says the man known to hold grudges for decades.
Winston's wisdom
How to live: "The great fortune is to ensure, without being indulgent, that you have as much experience and fun as you possibly can. That's the serious business of living."
Don't learn to accept the things you cannot change: "You most certainly should be able to change them and you have to keep on trying."
Sleep four to five hours a night, maximum. A 90-year-old who sleeps eight hours a night spends 30 years of their life asleep: "I thought that was a very sad waste of time."
Don't list your regrets: " You look back and think 'could I have done better?' But it's nothing I can do anything about now."
On whether he's an elder statesman: "No. You've got to think young. You can't just sit around filling out time."