Our culture is more than the result of who rules us

But he also had a word of caution. People in cultural movements, he said, were "always apt to run to machinery for a solution". "Machinery will never effect a cultural revival," he continued. "To imagine that a cultural revival will gush from the establishment of a separate legislature is like digging a well without making an inquiry into the presence of water-bearing strata."

Buchan was surely correct. He reminded MPs the "greatest moment" in Scottish literary and artistic history had come at the end of the 18th century when "Scotland was under the iron heel of Henry Dundas," and indeed decades after Buchan's death Scotland experienced another cultural renaissance during the 1980s and 1990s. Neither, arguably, had been predicated upon contemporary constitutional structures.

Nevertheless, it's striking the so-called "cultural case" for Scottish independence remains a fixture of the current constitutional debate. On Saturday, for example, the usually engaging National Collective movement announced plans for a "major cultural event" likely to take place next summer. Organiser Michael Gray said it would aim to "build on the cultural excitement and energy that is in favour of Scottish independence".

As The Herald's Arts Correspondent Phil Miller recently observed, Better Together can't really compete when it comes to artistic support for the Union, but that struck me as rather besides the point: for what precisely is the cultural argument for independence?

In an article earlier this year, the academic Alan Riach boldly declared that it was the "only" argument for independence.

"It was there long before North Sea oil was discovered," he explained, "and it will be here long after the oil has run out. It is the only distinction that matters." The arts, added Mr Riach, provided the "fuel and fire" which made imagination possible, a rather vague notion that also underpins the National Collective.

Yet such statements don't lead anywhere particularly useful, for it can't reasonably be argued the Union somehow constrains Scotland's cultural life. As the Scottish Government's White Paper conceded, "Culture and heritage are already the responsibility of the Scottish Parliament", although you wouldn't know it from listening to some advocates of independence, a lot of whom appear to be trapped in a retro Scotland where Westminster still calls the cultural shots north of the border.

This can all too easily manifest itself as anti-Englishness, for example when the writer and artist Alasdair Gray put pen to paper in a pungent essay entitled Settlers and Colonists.

This critique is driven by a belief that English people don't understand Scottish culture and are only interested in furthering their own careers, a line of argument revived (albeit more politely) in a new book, Scotland: A Creative Past, An Independent Future by the prolific cultural commentator Paul Henderson Scott.

Like Gray, he names and shames Vicky Featherstone (the first director of the National Theatre of Scotland), and also Sir Timothy Clifford (formerly of the National Galleries of Scotland), as examples of the problems "likely to arise when people with no previous knowledge of the Scottish tradition are appointed to lead Scottish cultural organisations".

And like Gray, Henderson Scott doesn't appear to think this is a problem when applied in reverse (ie Scots running London-based cultural institutions, as of course many do). Henderson Scott also holds the cultural case for independence to be crystal clear.

"It is remarkable two ancient nations which have shared the same government for more than 300 years are still so distinct in their cultures," he writes.

Paradoxically, he too acknowledges all Scotland's main cultural objectives have been achieved under devolution, with the exception of broadcasting, on which Henderson Scott has long campaigned.

There is, surely, a distinction to be drawn between different sorts of culture in this respect. In terms of the culture with which most people engage, as measured by the pop charts, cinema audiences and best-seller lists, it's difficult to discern differences between Scots and those from the rest of the UK. In high culture, too, there is little difference; only when the argument is boiled down to indigenous Scottish languages can a more convincing case be made.

Similarly, the recent White Paper dwells at length on broadcasting but has surprisingly little to say about culture. "An independent Scotland will enable culture and heritage to flourish", it states blandly.

Scotland's Future is on more solid ground when it comes to articulating a different approach: "This Government does not measure the worth of culture and heritage solely in money - we value culture and heritage precisely because they embody our heart and soul, and our essence." In other words, you'll get more dosh in an independent Scotland, although in common with every other spending commitment in the White Paper, associated costings are conspicuous by their absence.

It's this pitch Culture Secretary Fiona Hyslop has used to win over the already largely on-side Scottish arts fraternity, deliberately contrasting herself with UK Culture Secretary Maria Miller's more cost-benefit orientated analysis of the arts.

Yet at the same time is it really unreasonable - particularly in these straightened times - to ask those in receipt of public money to justify its use? I suspect Scottish public opinion is not as generous on that point as those in the arts.

The cultural case for independence also doesn't sit very well with the utilitarian, civic Nationalism being pushed by Nicola Sturgeon et al. It's all a bit Soviet, although others, including the First Minister, are more comfortable with this sort of stuff. As Alex Salmond put it in one interview (speaking of Scotland and England): "You couldn't get two more different cultures." But again, he made little attempt to explain precisely how that was so.

"Better Together campaigners", wrote Phil Miller in Saturday's Herald, "have not elucidated what they believe are the benefits of staying in the UK for the Scottish cultural sphere." That's a reasonable point, but nor have supporters of independence made a compelling contrary case beyond pseudish stuff about imagining a brighter future.

In truth, and as Buchan well understood, Scottish cultural life is driven by factors beyond constitutional machinery.