It shows to what depths the perception and coverage of British politics has sunk just now when everything is perceived in terms of personal advantage and cynical strategy. ‘Why has he taken that side rather than the other?’ Obviously because he’s looking to lead his party in the future. ‘Why has she changed her mind on this or that issue?’ Clearly because she thinks it will get her new friends. ‘Why does he seem to have abandoned principles he espoused forty years ago?’ Self-evidently because he’s not a man of principle at all, but a hypocritical opportunist, just like all the rest. ‘Why is politics so despised amongst ordinary people?’ That’s why.

As an academic, and it may be only because I’m an academic, I find this way of thinking depressing. In some cases the charge of cynicism may be justified: I wouldn’t trust Boris further than I could throw him, for example (and with my arthritis that’s not very far nowadays). Too many politicians are merely tacticians, playing politics like a game. Public school probably does that to you, as the only way of keeping your head above water, as you try to swim against the social tide. Blair was a master at this sport. And of course he was a success, by the rules of the game.

But changing your mind, or choosing one team to play for rather than another, doesn’t imply this necessarily. In my field it’s considered to be a mark of intellectual honesty and moral virtue if we change or modify our theories in accordance with new times or new evidence. Sticking rigidly to a view I formed forty years ago would not be a reason for others to trust my judgment on historical matters today. As long, that is, as I had good reason to change my view. If so, then it would be ludicrous if people regarded me as less ‘principled’ for that reason alone; and insulting if they assumed I had changed my mind for personal career reasons, or in order to make friends. There may be some academics like that, but I would not accuse even my sworn scholarly enemies – Niall Ferguson, for example – of forming their views simply in order to better their positions.

So it annoys me when Corbyn’s critics harp on the fact that he used to be anti-the EU forty years ago, yet is campaigning on the ‘Remain’ side today. It’s obvious from everything he’s been saying recently that he is still just as hostile to the EU as present constituted – as a neo-liberal scam – as he was back in the 1970s. That’s the principle behind his hostility: not an anti-European, but an anti-capitalist one. It’s mine too. We’re both sticking to it. The question now, therefore, is which way to vote in order to damage neo-liberalism and restore some socialism to Europe. That’s not a matter of principle, but a judgment call. Is Brexit the way – paving the way for an even more neo-liberal government in Britain, while doing nothing to help the socialist cause on the Continent? Or staying in, with a fairly good chance (I’d say) of Labour’s forming a British government some time afterwards, which could then work with the burgeoning anti-austerity movement in Europe, to – for a start – scuttle TTIP? You may think this is a naive hope, as it may well be; but in that case it’s simply a misjudgment, not a betrayal.

It’s a fine choice, and the answer isn’t obvious. But it’s clearly one that shouldn’t be dictated by the position one reached all those years ago, without any thought – the sort of thing we academics engage in all the time – being applied to it. That’s a lazy way of coming to judgments, and of judging the judgments come to by others.