Historians are disputatious people. One of them says something is white? Others will say it's black. One scholar says that up is down? Well. Others will soon appear to say that up was, after all, very up all that time. Partly that's a generational effect, as each group of doctoral students rightly overturns the wisdom of their masters; partly it's a way to make a name and a career for oneself; partly it's all to do with the availability of new sources, particularly in contemporary history, which allows each orthodoxy to be questioned in its turn. Then there's the effect of fashion. The economic and social history boom of the 1960s and 1970s, with its overt Marxist and economistic turn, gave way during the 1980s and 1990s to histories of discourse, language and identity; and then, during the 2000s, to a fissiparous, complicated history of the local, the fractured, the 'de-centred' and (perhaps) the surprising. No-one's sure where we've got to now, but we've got somewhere. We know a lot more than we did in the 1960s, though we've had a load of rows along the way. Polite ones, you understand.
One of these debates is very simple: what is the role of structure, and what is the result of agency, in historical change? That is to say, the big basic effects of our time - deindustrialisation, perhaps, or the information deluge of the online age, or the (return to) globalisation - clearly set the scene for the enormous forces that shape our lives. But loads of historians - not all conservatives wedded to their narrative stories of powerful people doing apparently momentous things - would say 'hang on a second, what's the role of personal choice here? What about chance, that great decider? What about lived lives, and their ability to bend and remake those so-called "impersonal forces" we're talking about here?' They're both right, by the way, and the skills of both types of historian are needed to build up a really clear picture of any period in the past. In part this depends on what you're looking at - what your question or your problem is. Want to know about meat-eating in the late nineteenth and early twentieth centuries? You'd better bone up (sorry) on the history of refrigeration and shipping costs, as well as on the environmental transformation of the non-European lands (hello, New Zealand) on which all that protein was grown. But want to understand something very different - let's say the course of Britain's Second World War campaigns - in any detail? You can't do that, in the example we've chosen there, without plunging into the complicated life story and personality of Winston Spencer Churchill.
Anyway. Let's give you an example of what we mean, for one of the great moments of 'structure' and 'agency' is nearly upon us: the impending campaign as to whether the United Kingdom should remain a member of the European Union.
Elements of structure? Well, the competing claims cultural Americanisation and Europeanisation, in flux and playing one against the other; Britain's trade with the EU, which has boomed so much since the 1960s; the lure, on the other hand, of new markets in India and China; mounting public fear about immigration, evident at least since the turn of the millennium; and so on. Chunks of agency? The Prime Minister, David Cameron (above) seems at the moment to have made a grave mistake by copying his predecessor, Harold Wilson, in opting for a re-negotiation of Britain's terms of membership. Coming back to the voters with some good and worthy - but dull - compromises, it just all looks a bit shoddy and tawdry. It's as if Mr Cameron is trying to fool his electors (he isn't, really: he's just desperate to protect his job and his legacy). Labour's accidental left-wing leader, Jeremy Corbyn, would probably prefer Britain to leave the EU, in his not-so-secret heart of hearts, so he doesn't exactly sound strident in its defence - and nor will Labour (or the increasingly left-wing and isolationist trade unions) really, really strain every sinew to keep the UK inside the EU.
So there are great big forces in play. But there are also elements of chance, among our 'leaders' and their choices. An observation that doesn't end there. Maybe hundreds of boats will fill the Mediterranean in the early summer, frightening British voters into cutting ties with their neighbours. Perhaps the increasingly-shaky European banking system will implode, taking what remains of the Euro's credibility (and much of the EU's claim to legitimacy) with it.
How this balance of context and choice play out will decide the question. It might be very tight. There might only be a few tens of thousands of votes in it (it's impossible to say at the moment). But however it falls, that will then have knock-on effects in the future. If Britons vote to leave the EU, with some of those elements of chance deciding the day in a very, very narrow way, Mr Cameron will probably have to resign. He may then be replaced by a much, much more right-wing leader (even the deeply unconvincing Liam Fox is being touted for this role among the membership, as much of a right-wing mirror-image of Jeremy Corbyn as it's possible to get). And then Labour might have a chance, at the next General Election, of salvaging something - anything - from its likely very heavy defeat.
It's also very likely that, in the event of a 'Leave' vote, Scotland will then itself decide to leave the UK, so it can defend its European identity and security. Who could blame them, really, if they had voted by something like 70%:30% to stay in the biggest trading group in the world, and then English and Welsh voters had pulled them out anyway? Anyway, that issue's for another time.
The point here is that lots of commentators will then say 'ah, it was coming all the time. English nationalism; Scottish nationalism; the parochialism and populism of the age of rage; the sense that the governing elite at Westminster were far, far, far away from the voters; it was all there, all the time'. But maybe it wasn't. Maybe a poorly made, cramped campaign that boxed the Prime Minister in from the moment he made his 2013 Bloomberg speech was a tactical misstep that doomed us to leave. Maybe Labour's turn towards a Marxist Eurosceptic who can only make a very tepid case for Europe (and who very few voters listen to anyway) thrust us out of Europe. Maybe something will just turn up - a migrant crisis, a banking crash - that is decisive in pushing us out.
There's structure there all right. But there's also agency. And there's the blind, brute, base force of chance. Welcome to the history of the now.