‘I’m getting rather tired of me,’ begins Jan Morris in one of the diary entries in Thinking Again, almost certainly the writer and journalist’s last book. She is only half kidding. This collection of essays and whimsical daily musings — a sequel to 2018’s In My Mind’s Eye — is both a deep dive into the charming and erudite mind of Morris, now 93, and also a moving meditation on just what it means to be old. Morris was launched to fame in 1953 when, as James Morris, she was the first journalist to report on Edmund Hillary and Tenzing Norgay reaching the summit of Mount Everest. She experienced a different type of fame altogether when in 1972 she had gender reassignment surgery in Morocco. Over her career she was written more than 40 books — notably her Pax Britannica trilogy on the British Empire — and raised four children with her ex-wife and now civil partner Elizabeth. It’s no wonder that she’s a little tired.

This book is every bit as witty as the last one, and touches with insight and good humour on everything from Brexit and Harry and Meghan to Welsh nationalism and being ‘big on goats’. Much of it is self-consciously inane, and part of its charm is that it feels as if we are having a natter in person with the author herself.

But it is sadder than the last book, I think. ‘I am well past my sell-by date,’ she claims with a wink. But then, ‘humanity is hardening’, she adds, as she rages against ‘these cyber-days’ and the ‘disadvantages’ of old age. ‘Never get old!’ If old age was once a bit of a joke, ‘grist to a writer’s mill’, it is also a very serious business indeed. Elizabeth has developed dementia, and Morris recounts with blistering honesty her own clumsy reactions to dementia’s challenges. Often she is irritated, then remorseful. She may be urbane, droll and commendably cheerful, but she is human.

Nostalgia may explain Morris’s surprising thoughts on Donald Trump. ‘I have always rather liked his political style, as against his personal ideas’, and later, ‘his appeal to old-fashioned patriotism may be deceptive, but at least it is comprehensible’. She doesn’t much explain herself on this point, but she does have a special place in her heart for the Great Republic, on which she wrote several books, and laments ‘the progressive disintegration of the American reputation’. She longs for the true grit of the space race.

Despite her ‘loitering somewhere between despair and resentment about the state of almost everything,’ there is much optimism and daily routine too. Morris starts every day with 1,000 paces, come rain or shine, sometimes along the seafront by their house in north Wales, more often towards the mountains with Snowdon’s peaks on the horizon. Every night she reads Anna Karenina and admires in Tolstoy’s characters a recognition of ‘the simple power of goodness’. She remains deeply hopeful about the next generation, delighting in the chutzpah of the young folk on the promenade and their manners in the café.

I don’t want you to think that this is grand or overly serious book. It is largely a pleasant one of comic curiosities, something to dip in and out of. Some views do feel half-formed, such as those on Trump, but then they are so swiftly followed by something frivolous — the idea that Morris’s favourite TV programme is the lowbrow American comedy Two and a Half Men made me laugh out loud — that perhaps we are not supposed to take it all so much to heart. ‘That’s the way it goes,’ as Morris writes cheerfully in her classic signing-off style. ‘Keep smiling anyway!’