Throughout adulthood, the majority of our waking lives are spent at work. We develop friendships and enemies, entire philosophies and narrow skills that are exclusive to us. So ensconced are we in these enclosed worlds that we rarely – if ever – pause to imagine life in the thousands of professions and trades that keep a modern, post-industrialised world functioning.

The Office was a brief satire on a life that was strangely familiar to most of us, but generally we know almost nothing of the armies of our fellow citizens who toil in obscurity to keep the nation running. From a supermarket warehouse to a biscuit factory to a huge accountancy firm, Alain de Botton has taken himself to the heart of these cathedrals of industry for his new book, The Pleasures and Sorrows of Work.

It is an exploration of the joys and perils of the modern workplace, revealing what other people do all day – and night – to make a frenzied, complicated contemporary world function.

In undertaking these journeys into engine rooms of society, de Botton asks the big questions: What should I do with my life? How can I combine earning money with attaining fulfilment? What will I have achieved by the end of my career? “It is surely significant that the adults who feature in children’s books are rarely, if ever, Regional Sales Managers,” he writes. And asks the question: “What job did your 16-year-old self choose for you?”

The Logistics Park

The largest warehouse in the logistics park belongs to a supermarket chain, which throughout the night receives dispatches from food suppliers and recombines them for onward delivery to stores across the country. The aisles of an average supermarket contain 20,000 items, 4,000 of which are chilled and need to be replaced every three days, while the other 16,000 require restocking within two weeks. There are 50 lorry bays running along the length of the building and vehicles arriving and departing at a rate of one every three minutes.

Inside, staff circulate between shelves, placing goods on to automated runways, which rush them to rows of steel cages lined up behind the loading bays, where they wait to be driven to a range of obscurely numbered destinations.

Components of the national diet race around on conveyor belts high above the ground: 30 cartons of crisps for Northfleet, 1,200 chicken drumsticks for Hams Hall, 60 crates of lemonade for Elstree. Human beings, once segregated into dietary categories almost as strongly as by religious ones, into the peoples of rice or of wheat, of potatoes or of maize, now fill their stomachs with unthinking promiscuity.

Time is of the essence. At any given moment, half the contents of the warehouse are 72 hours away from being inedible, a prospect which prompts continuous struggles against the challenges of mould and geography. Clusters of tomatoes still attached to their vine, having ripened to maturity in fields near Palermo at the weekend, are exchanging the destiny seemingly assigned to them by nature to try to find buyers for themselves on the northern fringes of Scotland before Thursday.

Blind impatience is equally evident in the fruit section. Our ancestors might have delighted in the occasional handful of berries found on the underside of a bush in late summer, viewing them as a sign of the unexpected munificence of a divine creator, but we became modern when we gave up on awaiting sporadic gifts from above and sought to render any pleasing sensation immediately and repeatedly available.

If only security concerns were not so paramount in the imagination of its owners, the warehouse would make a perfect tourist destination, for observing the movement of lorries and products in the middle of the night induces a mood of distinctive tranquillity; it magically stills the demands of the ego and corrects any danger of looming too large in one’s own imagination. That we are each surrounded by millions of other human beings remains a piece of inert and unevocative data, failing to dislodge us from a self-centred day-to-day perspective, until we take a look at a stack of 10,000 ham and mustard sandwiches, wrapped in identical plastic casings, assembled in a factory in Hull, made out of flawless cottony-white bread, and due to be eaten over the coming two days by an extraordinary range of our fellow citizens which these sandwiches urge us to make space for in our inwardly focused imaginations.

This gargantuan granary is evidence that we have become, after several thousand years of effort, in the industrialised world at least, the only animals to have wrested ourselves from an anxious search for the source of the next meal and therefore to have opened up new stretches of time – in which we can learn Swedish, master calculus and worry about the authenticity of our relationships, avoiding the compulsive and all-consuming dietary priorities under which still labour the emperor penguin and Arabian oryx.