When you are well into your 10th decade and can reflect on a life of rich variety, erudition and achievement in so many fields, it is probably quite irksome to be grilled on that brief part of it when you spent your leisure hours chasing an inflated pig's bladder around a field.

If so, Logie Bruce-Lockhart keeps his frustrations well disguised over the course of a fascinating conversation that is spiced with self-deprecating wit and insights of almost forensic precision. Those same qualities illuminate his recently-published memoir, Now and Then, This and That, which reads like a kind of real-life version of William Boyd's Any Human Heart in terms of its span and underlying wisdom.

Yet there is no getting away from the fact that his distinction, in many eyes, rests on his membership of one of the great dynasties of Scottish rugby. His father, JH (Rufus) Bruce-Lockhart played two Tests for Scotland, in 1913 and 1920, and would almost certainly have played more had the Great War not intervened.

Bruce-Lockhart's brother, Rab, won three caps between 1937 and 1939, another career curtailed by conflict. His son Duncan was widely tipped to continue the family tradition when he made a couple of appearances for Scotland B in the early 1980s, but persistent ankle problems prevented him from reaching the very top.

Bruce-Lockhart himself made five appearances for Scotland. The first was in 1948, when he turned out at centre and helped the side to a 6-3 win over England at Murrayfield; two more were won in 1950 and another two in 1953. Now 92, he remains one of Scotland's oldest living internationals.

As a general rule, the news that an old player has gathered his recollections and ruminations into book form usually provokes a kind of dread, as few of those tomes depart far from the theme that things ain't what they used to be and the handcart that is taking us all to hell is well into its journey. In which light, Bruce-Lockhart's work is a glorious, uplifting and life-affirming exception. Few authors have ever counted their blessings quite so eloquently.

And in an age when guidance is generally dished up in the form of glib aphorisms, it is humbling to be presented with wisdom born of real experiences that range from joyful to heart-breaking. "How lucky I've been!" writes Bruce-Lockhart towards the end of his book. "In spite of so many horrific and unjust sufferings, in which no-one can hope to avoid some part, it is an unbelievably beautiful world [...] I had lots of love and laughter, a fair share of cock-ups, good friends and, above all, the supreme and undeserved blessing of a supportive, forgiving and unreasonably affectionate wife and family. Nothing, in the end, matters more".

Professionally, Bruce-Lockhart spent his working life in education, the final 27 years of it as headmaster of Gresham's School in Norfolk. Before he settled into that career, however, he followed many of his generation to war, seeing service as an armoured car commander as the Allies swept through northern Europe in 1944 and 1945. Later, his skills as a linguist became invaluable as he was retained to help manage a teeming refugee camp. In that role, he found himself at Belsen just a few weeks after it had been liberated.

So, like I said, talking rugby with such a figure as Bruce-Lockhart can seem absurdly trite. But for all that he considers himself privileged to have had a solid, Presbyterian upbringing, his book shines with an understanding that life is a pursuit of joy, not redemption. And Bruce-Lockhart unquestionably brought that to the field of play.

The late and inimitable Frank Keating quoted Bruce-Lockhart's thoughts on the principles of fly-half play in an approving passage of his book The Great Number Tens. "To handle beautifully and pass swiftly [...] to kick or thrust your way beyond the advantage line [to use accurate kicking to keep play in your opponents' half [...] not to line back too steeply in the backs [...] to cultivate the swift long pass to an outside centre lying fairly flat in order to outflank drift defence."

By all accounts, Bruce-Lockhart played the game he advocated, which begs the question as to why he won just a handful of caps. Goodness knows, Scotland could have used more of him, for the early 1950s was a gruesome era for the national side. Seventeen Tests on the trot were lost between February 1951 and February 1955, during which time Bruce-Lockhart was called upon just twice. "It seems strange that in recent rather barren years, Scotland have needed him so little," wrote one newspaper at the time. "One wonders that the Scottish selectors can afford to overlook him," said The Times.

And yet, there is no bitterness. "I had made an arrangement with the school that I would not play during the first half of the season," Bruce-Lockhart explains. "I was busy teaching and I would coach the school teams until Christmas. The selectors would have had to pick me blind because they had not seen me playing. On the other hand, I kept reasonably fit by coaching every afternoon, and I was able to practise and develop my skills by doing that."

Those skills, honed through perseverance and repetition, were the essence of his craft. Consideration of which also provokes his solitary suggestion that rugby may have lost something along the way.

"The players of today are far better than we were in so many ways," he says. "They are bigger, stronger, more intensively coached, more subject to team plans and the defensive schemes and all that sort of thing. On the whole, we didn't do anything like that. Playing for Scotland, I was introduced to my scrum-half on the day before the match, which would be ridiculous now.

"But there is one way the players of my time were a little more skilled than the players of today, and that was in beating a man. You are now expected to take a man out, to offload and get over the gain line, but we were taught to sidestep and dummy and swerve, and reckoned that, given five yards, we would beat the opposition."

Small wonder that Bruce-Lockhart's enumeration of the greatest players he has seen leans heavily towards those who have shown the same will o'-the-wisp qualities that he sought to develop in himself.

"I think the one who stands out for me was Bleddyn Williams, the Wales centre," he says. "He had a marvellous sidestep, probably the most ferocious sidestep I ever saw. Haydn Tanner, their scrum-half, was very good too. There was an English fly-half just before me called Tommy Kemp. He had beautiful hands, a wonderful kick and was very dependable. He was an elegant player, but he put on weight during the war and became more physical. It was strange how he changed.

"Of course, I was a great admirer of Phil Bennett and Barry John as well. Of the Scots, I loved the way Gregor Townsend played. He would be among the top half-dozen fly-halves I have ever seen. I suspect that is why Glasgow have come to the fore with him as coach."

Bruce-Lockhart was a regular visitor to Murrayfield until about a dozen years ago. As agile as his mind might be, he admits that the body has struggled to keep up in recent years. "At 92 I'm not a great traveller," he confesses. "And I don't like sitting on uncomfortable seats when you can see it so much better on the telly. It is very expensive, too. You go up, meet old friends, drink too much and have to pay for your hotel and a long journey. It is not a thing for old men."

Maybe not, but rugby would be so much the weaker if it ever stopped paying heed to old men like Bruce-Lockhart. He talks fondly of going to games with his old friend Tommy Macpherson, and it is only with a little prodding that you realise he is talking about Sir Thomas Macpherson, celebrated war hero, most decorated British Army officer of the Second World War, and brother of GPS Macpherson, one of the stalwarts of Scotland's 1925 Grand Slam side.

No sport should ever forget its past. Or its place. "What do they know of cricket who only cricket know?" asked CLR James - echoing Rudyard Kipling - in Beyond a Boundary, his brilliant social and historical analysis of the game that had been his life. It is a question that could be asked just as easily of many rugby players nowadays. But not one you would ever dream of putting to Logie Bruce-Lockhart, a man who knows much more about rugby for the simple reason he knows much more than rugby.

Now and Then, This and That, by Logie Bruce-Lockhart. Larks Press, £14.00

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