Global capitalism, as a system, simply doesn’t work. Russell Brand’s new book provides the proof. As does my new book. And the hundreds of other new books that are just out. And the Sainsbury’s advert. And all the current adverts for booze and perfume, chocolates and jewels, supermarkets and computer games. The gaudy, twinkly proof is going up all around us as the last of the leaves come down. It’s called Christmas.

On the face of it, Christmas seems like the most naked celebration of capitalism – and by “naked”, I mean the opposite: wrapped, adorned, decorated and sparkling. It might be dressed sexy but, by God, it’s dressed. Or perhaps by Satan. Or Santa. Or Setanta. Which is doubtless doing a Christmas deal on festive football with the opportunity to treat someone special to a banquet of motor racing in the new year. This is capitalism warmly enveloped by fur and wool and silk and diamonds. It’s retail at its most meretricious. Shopping as goddess and whore, love expressed with money and love bought.

But the pre-Christmas shopping frenzy is not really the callous manifestation of the free market that it seems. At the core of our midwinter festival is something fundamentally irrational, an urge a robot would never understand: a need to make merry, to paint the town glittery, to lavish one another with food and gifts purely because it’s got so dark. The sun has gone away and our fears are bubbling to the surface, so we have to dispel them with a big slug of the hard stuff. We must celebrate even though there’s nothing to celebrate. Nothing auspicious has happened other than our continued survival. Yet every winter, since long before Jesus was even a supernova-sized glint in his Father’s ineffable eye, we have a mad party to keep ourselves sane.

This huge quantity of panic buying must be an even more troubling spectacle for those who believe in efficient markets than it is for pious Christians. To people who have faith that the world can heal itself through the unfettered interaction of economically rational individuals, and that, if capitalism were allowed to operate freely, there would be no more slumps and bubbles because the invisible hand of the market would guide everything to its rightful price, the seasonal rush must seem like an orgy of blasphemy.

Christmas is an annual bubble – an irrational buying fever that’s actually scheduled. We know it will come and, like all bubbles, we know it will end. Unlike most bubbles, we also know precisely when it will end. The huge signs advertising a collapse in prices are already stacked in department stores’ stockrooms as the final spasm of Christmas Eve top-whack spending is taking place. At this time of year, the invisible hand gets delirium tremens – possibly from the number of drinks the invisible mouth is sticking away.

Looked at with a Scrooge-like economist’s hat on (gift idea for an accountant!), this makes no sense. Millions of people are each buying hundreds of things they don’t need – often luxuries they can scarcely afford – and at a time when such items’ prices are artificially inflated because everyone else is also buying them. Wait a couple of weeks and jumpers with reindeer on, chocolates in stocking-shaped presentation packs and sacks of brussels sprouts will be going for a song. The rational economic choice, even for an alcoholic gourmand who likes wearing jewels, would be to schedule a knees-up for 10 January.

And, as every shopkeeper will tell you, a huge sector of our economy depends on this. Our already beleaguered high streets would be wastelands without it, the hellish out-of-town malls exist primarily to harness this “golden quarter” of spending. The capitalist dream that western economies aspire to live is sustained by a crazy retail spike caused by a bastardised form of religious observance. It’s like what happened on Easter Island but, instead of giant stone heads, we get unimaginable quantities of Quality Street.

Quality Street is a good illustration of the system. When buying chocolate for ourselves, we seldom buy an assortment. Few of us have palates that favour such a wide variety of flavours. If you like strawberry creams – and such people must, I imagine, exist somewhere – you can just buy strawberry creams. You can structure your sweet eating so that every mouthful contains cloying pink goo. You don’t have to fight over the precious strawberry cream Quality Street with your loved ones (I’m attempting the further imaginative leap that they like strawberry creams too – this is making me feel queasy). A society has never evolved wherein people socialise in groups whose tastes in chocolate vary in direct proportion to an assortment’s range. Maybe when we construct such a society, we will finally find peace. More likely, everyone will just think everyone else is gross.

As things stand, as much as 30% of the chocolates aren’t really wanted. By purchasing an assortment, we’re literally buying into a system of deliberately acquiring unappreciated things. The loud ties, hideous jumpers, bottles of Drambuie, dubious perfumes and aftershaves, second copies of DVDs, panettones and stultifying board games are all an extension of that. And, yes, books too.

Autumn-published books are tapping into all this as surely as reindeer deely-boppers. Many people will buy many books this season, for themselves and others, which will be cherished and read from cover to cover (mine, for example – everyone will love mine). But anyone with a shelf will tell you that’s not the only sort of book. There are also the “it’s the thought that counts” books – the thought in question being the generous one of the person who gave it to you, not any of the author’s musings, by which you will remain as unaffected as the book’s spine is by creases. This is vital. Publishers and bookshops are in enough trouble as it is. Can you imagine how bleak the future of literature would look if book sales were reduced to the level of book reading? Gutenberg’s legacy is secured, not just by voracious readers, but by unopened books, gathering dust like a purple Quality Street in a household of the nut allergic.

Deep down, this must be what most of us want: bookshops and publishers, perfumiers and chocolatiers, bustling high streets and an abundance of sweet and smelly and sparkly and interesting objects. Christmas extravagance only continues with our collective consent – the society it engenders is closer to what we want than the one an unsentimental market would provide. In the end, our futile midwinter merriment comes from the heart. And maybe that is a reason to celebrate.

David Mitchell’s new book, Thinking About it Only Makes it Worse (£18.99), is out now. To buy it for £13.49 click here