ON this day, our minds naturally turn to Burns, and his unwavering commitment to Scottish nationalism (Such a Parcel of Rogues in a Nation), British Unionism (Does Haughty Gaul Invasion Threat), and egalitarian internationalism (Is There For Honest Poverty).

Despite constant attempts to co-opt him politically on biographical or literary evidence, one indicator of Burns’s genius is that he exhibits them all; a universality and ambiguity which many see as an essential component of great literature. Scott Fitzgerald called it “the ability to hold two opposed ideas in mind at the same time and still function”; Walt Whitman, with customary understatement, declared: “Do I contradict myself? Very well then I contradict myself (I am large, I contain multitudes)”.

A later luminary of Scots poetry, Hugh MacDairmid – whose own politics were similarly all over the shop, embracing nationalism, internationalism, communism and even (briefly) fascism – thought this not just a characteristic of literature, but a characteristic aspect of Scottish literature in particular.

He popularised the notion of “the Caledonian antisyzygy”, inspiring numerous academic theses comparing James Hogg’s Confessions and Robert Louis Stevenson’s Jekyll and Hyde with any other works of Scottish literature that lend themselves to notions of duality. These have replaced shipbuilding and mining as one of our national industries.

Syzygy (from the Greek for a yoke) is an unhelpful word, like “sanction”, that has antonymic definitions to start with – it means either “conjunction” or “opposition”. Antisyzgy, even more redundant and contradictory, not to mention ugly, is usually taken to mean “the yoking together of irreconcilable objects”.

Cometh the hour, cometh the word, though. If ever nationalism, unionism and internationalism alike needed a handy term to encompass what the naïve observer might have thought incoherent, contradictory or downright delusional in their respective positions, it is now.

It lets Theresa May claim Brexit (which she opposed) means independence from the EU and sovereignty and strength for the UK, while her version leaves almost all significant power with Brussels and recklessly endangers the Union. Or unions. Attention is naturally on Northern Ireland and the equal dangers of either backstop or hard border, while the PM alienates Unionists and nationalists alike. But there’s a similar inconsistency in refusing the Scottish Government a say in post-Brexit trade, while insisting that such decisions are best made at more local levels.

Few people – certainly no one drawing up the current plans for Brexit – seem to have considered that a UK withdrawing from a large union might, given the nature of its constituent parts, face arguments that “taking back control” could be extended further.

Not that that’s necessarily a logical position for nationalists, who lost a referendum that would have meant leaving the EU as well as the UK but now, because the UK wants to leave the EU, want one to leave the UK in order to stay in the EU. Fortunately for Nicola Sturgeon, Mrs May’s inability simultaneously to manage cake-eating and cake-having offers the SNP an opportunity to look as if they can – even if it involves a Great British Bake-Off’s worth of contradictory things before breakfast.

The First Minister gets cheerfully to demand another independence referendum on the basis of Scotland’s divergence in the Brexit vote, and to complain when she’s refused one. This suits her fine, since she would lose it because (a) support for independence hasn’t grown (b) dissatisfaction with her Government has and (c) Brexit shows how complicated and – according to Ms Sturgeon herself – potentially disastrous, such divorces are.

Political discourse is in its current atrocious state because, whatever the practical or theoretical merits of nationalism, unionism or the EU, almost no one with a dog in the fight is capable of presenting them honestly. Indeed, fanatical supporters of independence, supporters of Leave and supporters of Remain have more in common than they suppose.

For the ultramontane in each camp, any argument can be levered, or ignored. You can advocate any referendum that you think you might win, and resist any you fear you’ll lose. In the event you’ve already lost, you advocate another go. If you’ve won, you complain you haven’t been given what you voted for.

If the financial predictions suggest your preferred options are going to lead to disaster, you ignore them, either because that hasn’t happened yet and probably won’t, or because the argument isn’t about economics, anyway, but something more important than temporary economic prosperity, like culture or self-determination.

If the economic evidence shows that your previous claims were piffle, you ignore that, too. It either wouldn’t have happened if we’d done things your way, or it will all be different in the future, because, well, reasons.

Almost all political opinions involve contradictions, and almost all theories of political philosophy, from David Hume on, have concluded that part of the nature of politics is that no one gets everything that he or she would like. To recognise that is not to accept that you need to compromise on every principle: everyone’s entitled to a dream, and it doesn’t help to indict other people’s as treason.

Scottish independence, or a UK of united, devolved nations outside the EU, or even a single European state that does away with constituent nations, are all coherent political ideals. The majority of people feel – at a minimum – dual identities, whether that’s Scottish and British, or Scottish and European (but not British), or European but anti-EU, or some other permutation.

None of these beliefs, however, can be held without accepting that they are not universally shared, or by ignoring external realities. They must be advanced by persuasion, reason and evidence.

Insisting on one particular kind of “real” Brexit, while ignoring what the EU, or the Commons, or public opinion, or industry will wear, isn’t that. Nor is arguing by satellite link from Davos that a People’s Vote will be “real” democracy, as the last vote wasn’t. Nor is seeing those quarrels only through the lens of whether they make Scottish independence more or less likely, and adopting any and every approach as circumstances suit.

Reality is prosaic; it demands matter-of-fact politics, and Parnassus is not a hill to die on. No matter our capacity to imagine political solutions that give us everything we want, facts, as someone or other once put it, are chiels that winna ding, and downa be disputed.

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