Jardine House was the tallest building in Hong Kong, a city with - back then - many more shanty towns than shopping malls.

Colour TV had just started replacing black and white, but only in the wealthiest of homes. And magazine ads featured doctors and airline pilots with pearly white Hollywood smiles, extolling the health benefits of cigarette smoking.

Beam us back to that book, Scotty! Now those brainy people at the London- based The Economist - the news magazine that weirdly eschews bylines - have undertaken a collective crystal ball-gazing exercise, albeit based robustly on current and keenly projected trends.

This ambitious work, penned by the cream of the magazine's editorial team, looks at sweeping and epoch-defining 'mega-trends' that are changing the world faster than at any time in human history.

Warp speed is the new paradigm, and it's going to accelerate. Abundantly buttressed with supporting facts and graphics, the book's 20 chapters take us for an ostensibly informed peek into the year 2050.

Right away, this work does hedge its bets, though. Not-so-boldly announcing that 'predicting the future is a guess', while positing on the same page that much can be determined from what we know, gives the reader an early sinking feeling.

The forehead-thumpingly obvious - Asian economic growth, world population increase, surging social media usage - are all lavishly explored, but the broader strokes don't amount to much more than one could get from any reasonably switched-on random dude with a daily newspaper habit.

Nevertheless, Megachange does take a fair crack at the Big Asks of tomorrow: how to fill nine billion stomachs every day in 2050? How to face down a chilling multitude of new security threats?

Much of Megachange is captivating and thought-provoking but it's also a flawed work.

One glaring overestimation here seems to be the scant attention given to the ominous forecast of escalating climate change. One lonely chapter? My teenage daughter's world - everyone's children's future - is going to be changed in myriad ways by global warming; now so grimly inevitable, in this reviewer's view, despite what the 'flat-earthers' say. Those hopeless optimists (or shrewd cynics) have huge stakes in the very industries that are doing the cataclysmic warming up of our planet.

Team Economist takes a bit of a stumble on this topic.

What lies ahead, according to this collective of writers and observers? They predict that our brothers and sisters across the globe in 2050 will be richer, healthier, more connected, more innovative and better educated. They also see - and I see some wishful thinking/ projecting here - a reduction in inequality between rich and poor.

Ahem.

The trouble is, this volume of officially approved futurology is bedevilled with so many weasel words and qualifiers - 'it may well be', 'probably', 'possibly', 'likely' and all their skittish chums - the reader might well be lulled into thinking these Economist eggheads are genuinely sceptical about their own forecasts.

However, they write with such elan and passion that one can't stop leafing through the pages, and marvelling at our high-velocity zeitgeist. Unfortunately, in the real world, developed economies with shrinking wealth gaps are few and far between. As are any nuggets of truly useful wisdom here.