Having been an obsessive traveller most of his life, beginning with termly commutes to Eton from his Indian parents’ home in California, Pico Iyer has lately been documenting the virtues of sitting still. A 2014 Ted Talk outlined the advantages – spiritual, environmental – of lying back and thinking of old pilgrimages or of nothing at all. This book is a mix of restlessness and the couch; it sees the author reporting on and recalling journeys through some of the world’s most divided and chaotic places – Kashmir, Jerusalem, Sri Lanka, North Korea among others – mostly in search of a bit of peace and quiet.

Iyer, now 65, has always been in thrall to clouds of unknowing, prizing glimpses of the ethereal in remote corners, clocking up air miles and epiphanies. He spent some time with Leonard Cohen in the five years he was a Zen Buddhist monk at Mount Baldy, near Los Angeles. He has been a friend and confidant of the Dalai Lama since they met at Dharamshala in 1974. He has often given the impression of a peripatetic personal Buddhism, without too much of the suffering. This particular quest – in search of the idea of paradise in the midst of political complication – is something of a summation of that roving life.

It begins in Iran, the place, Iyer argues, that gives us both “our word for Paradise and some of our most soulful images of it”. Thoughts of ancient Persia return Iyer to some of the most mystical moments of his own life – “the water softened courtyards that had bewitched me one candlelit evening in the Alhambra, the landscaped gardens depicting paradise around a marble tomb that had transfixed [his Japanese wife] Hiroko and me on our honeymoon, at the Taj Mahal”, and so on – but they also remind him of the words of the Sufi poet Rumi, that if heaven is within, then “one leaf is worth more than all of Paradise”.

That faith is mostly frustrated in modern Iran, where Iyer has to do battle with Shia bureaucracy to gain access to the Imam Reza shrine in Mashhad and the inner sanctums of the ayatollahs’ city of Qom. Once inside, he is alive to the ironies of a paranoid surveillance state keeping watch over ancient mysticism; the one tends to get in the way of the other. In order to protect his notebooks and emails from any prying theocratic eyes, he finds himself replacing the word “Iran” with the word “Paradise” to avoid repercussions.

He wonders, back in London, whether his almost pathological “longing for an ideal world might not be a kind of curse, even a heresy”. The rest of the book is a test of that particular complaint, what you might call the dharma burden, as Iyer scrolls through the motivations and abiding memories of a life on the road, the reasons he was always leaving home. It takes him back in his mind’s eye through a 1990 journey to the terrifying “People’s Paradise” of North Korea, all stage set and no script, and then to the time he and his wife stumbled on to the Cyprus Avenue of Van Morrison’s Astral Weeks in divided Belfast, and how he was transported in his head to the singer’s Edenic garden “all wet with rain”, and from there to Kashmir, the “paradise that had shone inside my mother’s heart, at least until she discovered Oxford”.

This latter transport is a physical as well as a spiritual journey. What Iyer finds in Srinagar is what he is at pains to locate in all of these quests: moments of transcendence in places surrounded by checkpoints and barbed wire. He locates his Kashmiri high drifting in a gondola on the lakes in the centre of the ancient city, floating among lily pads past houses from which images of the stern faces of fundamentalist clerics gaze out across the water.

He is a deft sketcher of haiku-like scenes: “From the sundeck of the houseboat named for inner peace, I watched four schoolgirls in spotless white salwar kameez, white shawls around their heart-shaped faces, paddle through the quiet of the morning.” Frustratingly, however, his curiosity rarely seems to take him beyond these surface descriptions; the characters he encounters – guides and strangers and friends – rarely take on convincing lives of their own. That quality lends this book a kind of fleeting mood, a sensual drift between disparate and often desperate places. The thread is the author’s elevated desire for a sort of aesthetic revelation, the godhead in the mud, but increasingly the places in which he seeks it – a cemetery in Sri Lanka, the ghats of Varanasi – tend to merge. At one point, toward the end, he finds himself at a place called Bridge of Heaven outside Osaka, to which one earthly response might be: are we nearly there yet?

• The Half Known Life: Finding Paradise in a Divided World by Pico Iyer is published by Bloomsbury (£16.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply