As I passed through York on the Flying Scotsman last week, the train chugged by the yard of the National Railway Museum, where two old carriages stood out in the frost.

To the adult eye, these specimens of a sootier, grimier age were as tempting as a dolls' house to a child. Peering out of the window, I wished I could hop off and spend the rest of the day looking at relics of the great age of rail.

There's no need to be nostalgic about trains, though. Even sleek, futuristic slow-worms that scarcely sigh, let alone hiss, as they reach the platform, have a mystery and allure that, for me, no car or plane can match. As for railway stations, be it light-filled St Pancras, the soaring beehive of New York's Grand Central Station, or Milan Centrale, a monument to brutalist architecture that's as impressive as the city's cathedral, I can think of few more atmospheric, exhilarating places.

Certain myopic individuals, though, would like to have seen trains consigned to history. Their arch nemesis was Dr Richard Beeching, chairman of British Rail, whose infamous report, The Restructuring of British Railways (which proposed cutting 5000 miles of track and 2000 stations), was published on March 27 1963. Fifty years on we are still living with the effects of that paper. Although Beeching and his colleagues tried to bury the train network, or at least anything other than lucrative mainline routes, the system has proved not just indestructible but, of late, astonishingly popular.

Even so, it was no surprise that the announcement that the forthcoming reopening of the Borders Railway will be economically unviable led to renewed calls to abandon this expensive and, its critics say, woefully inadequate line. Stopping at 10 stations between Edinburgh Waverley and Tweedbank, the village downriver from Abbotsford, Sir Walter Scott's stately home, this revivified route may be far from perfect, but it is a step in the right direction. As car travel loses its lustre, thanks to cost and congestion, and as towns grow increasingly inimical to anything on wheels beyond a taxi, bus or bike, rail is the cleanest, swiftest, most efficient use of fuel and investment, not to mention of a traveller's time.

To listen to the Borders Railway's critics, you'd think arithmetic was the only gauge by which a venture can be assessed. Obviously there must be rigorous evaluation of any such substantial outlay. But, since Transport Scotland maintains that the line will generate a 30% benefit greater than their £350m investment, to continue with it does not seem unreasonable. To halt it most certainly would.

True, the levels of benefit originally expected seem unlikely to materialise in the short term, though who can predict the impact the railway could have on those who might, once it's running, consider moving to the region? As accountants and venture capitalists very well know, spreadsheets and financial projections only ever tell partial truths. The scything of stations after Mr Beeching reported has shown too clearly and too late that the value of certain services cannot be expressed in purely monetary terms. Had the government of 1963 appreciated the crippling impact of station closures on countless small communities – a gradual erosion of economic, social and environmental health that in some cases has taken decades fully to be felt – it surely would have baulked before agreeing to such disabling cuts.

At the heart of the railways' predicament lies a profound lack of imagination. Had Mr Beeching spoken to a novelist or philosopher he might have realised that what in his day promised to become a brave new world of universal car ownership and limitless cheap oil could, like an uncapped tank of petrol, quickly evaporate.

The Borders Railway may not be the god-send everyone has hoped for, and its inadequacies will probably irk as many as it pleases. But to use the same narrow fiscal argument to destroy it as first led to its demise, and to ignore the invisible but not intangible benefits of using rail rather than road, seems profoundly self-defeating and short-sighted. The question we should really be asking is not how can this route be made more economically attractive, but can we really afford not to invest in railways, whatever the price?