By-elections are unforgiving affairs. Under relentless scrutiny, weak candidates fall apart. In Stoke, Paul Nuttall had two fatal defects. He had embellished his CV, and he was thick – which explains why he thought that the CV would survive. It did not. Otherwise, he might have won by persuading Tory voters to move to Ukip in order to defeat Labour; we can confidently assume that Stoke Tories do not think much of Labour. But by the final week, all momentum was gone. He had become a joke.

Apropos jokes, Ukip has a problem which goes deeper than Mr Nuttall’s powers of invention. In earlier centuries, there were itinerant musicians, especially on the continent: Pied Pipers without the rats. In woodcuts, they are sometimes depicted banging a drum while playing a bugle and wearing a cap with bells. Step forward Nigel Farage, who is the Pied Piper, indeed the Mr Toad,  of Ukip. He is also its Upas tree. Nothing can grow in his shadow. If any remotely serious figure emerges through the Ukip ranks, Mr Farage falls out with them. So he is left with dunces and dunderheads who cannot be allowed near a journalist, let alone a by-election.

Not that Ukip would find it easy to move into seriousness. The referendum result shot its fox. Mr Farage hopes to reinvent the party by replacing Labour in the North. Post-Stoke, that seems a harder task. Even with Mr Corbyn in charge, there is a deal of ruin in a Labour movement. Nigel Farage thinks that Ukip should concentrate on immigration, to appeal to the self-styled Northern working classes afraid of competition from Eastern Europeans, who actually want to work. An anti-immigrant campaign would win votes, and make it even more impossible for Labour to recover. But it would not be enough for a breakthrough. The British electoral system is also unforgiving.

Mr Farage has already made an enduring contribution to British history, for good or ill. He is a more important Poujadist than Pierre Poujade, who gave his name to the species. But for him, the UK would not be leaving the EU, or at least not yet. Yet his own future is unclear, partly because he is a one-man band. He may also have lost interest even in that. it is much more fun having dinner with the Donald than it is pounding pavements in the Potteries. One thing is clear, however. The aptly-named Mr Nuttall ought to retire to the obscurity from which he should never have emerged.

The sensible wing of the Labour party – let us call them the despairers – are praying that he would take Jeremy Corbyn with him. They have an obvious point. They also have a less obvious problem. Of course, Mr Corbyn is useless. Trying to lighten their misery with a bit of gallows humour, some despairers are saying that the results were not so bad. Labour did hold one seat. On that basis, they should hang on to half their current seats in 2020. Even so, Mr Corbyn has one asset. He is a believer. As he is a hapless feeble beardie suffering from the ravages of a vegetarian diet, it might seem paradoxical to describe him as a conviction politician, yet there it is. A socialist, he is convinced that fundamental change is necessary to liberate human potential and to use the resources of the planet to lift everyone out of poverty and oppression. The very suggestion that their leader might have any ideas worth considering would make Peter Mandelson, David Miliband, Philip Collins and all the other despairers roll their eyes and groan. But wait a minute. What do those eminent figures actually believe?

This brings us to the less obvious problem. In an interview that he gave on Saturday, Milipede major told us that he was in favour of “radical and substantive change.” That has a platform ring to it, but what does it mean? In the American boondocks, shyster politicians often base their rhetoric on “bomfog”: the brotherhood of man, the fellowship of God. Throughout its meretricious history, Blairism was sustained by an afflatus of bomfog. “Radical and substantive” is straight out of that lexicon.

The despairers may not realise it, but they have a credibility problem. Twice in modern history a Labour leader kept the Left under control, dominated British politics and made promises along the lines of “radical and substantive change.” Both won elections. Both were charismatic narcissists. In each case, promise and promises subsided in tawdriness and failure. Harold Wilson and Tony Blair were the two most morally negligible Prime Ministers in British history. So why should anyone buy a “substantive” from their political heirs? Agreed, no-one could accuse David Miliband of being charismatic. Yet there may be signs of narcissism. He has not forgiven his party for choosing his younger brother. Labourites were always keen to accuse David Cameron of feeling entitlement. That charge could be much more justly levelled at David Miliband. He and his friends do believe that they are entitled to be in power. They will work out what “radical and substantive” means when they get there. There are strong grounds for arguing that social democracy is now intellectually bankrupt and politically exhausted. The despairers are unwilling to address that problem, let alone answer it. Clever they may be, but that will avail them naught if they just hide behind empty phrases.

Poor old Corby does know what he would mean by radical and substantive. Thank God that he will never have the chance to practise it on the rest of us, but he deserves recognition for intellectual honesty. He could no more come out with a glib phrase than he could fly to the moon. To be fair to him, he has no interest in glib. The rest of us should be grateful to him – the only political gratitude he will ever receive – for helping to save us from Wilson or Blair Mk 11.

Theresa May is relishing the chance to assist him. She is the least charismatic PM since Alec Home, which has helped to win trust. She also has an opportunity, which she will not be able to exploit unless she moves beyond her caution zone. To be fair to her, Brexit is an enormous and necessary preoccupation. Yet it must not be allowed to consume the Government’s entire political energies. Because the other three parties are on the floor, the Tories have an historic opportunity to dominate British politics.

First, however, they will have to craft the language. This needs to combine Mrs Thatcher’s passion with Mr Cameron’s inclusiveness. It should be firmly in favour of hard work, the rule of law and personal freedom: after all, those are the values of the vast majority. It should not only contest Labour’s claim to the moral high ground: it should laugh it to scorn. Tories should delight in stealing the Left’s clothes, but be wary about stealing its language. Tories believe in social generosity, an uplifting cause, and in equality of opportunity, ditto. But they should steer clear of social justice and equality of outcome. That is the phraseology of left-wing totalitarianism.

Thus far, Mrs May has been a lucky Prime Minister and there is no sign that this will change any time soon. That said, luck is there to be exploited, as Margaret Thatcher did for many years. Theresa May tells us that she admires Geoffrey Boycott, which is wise. She will need the old curmudgeon’s grit and tenacity to fight her way through Brexit. But to consolidate her hold on the electorate, she should think of another cricketer: the greatest post-war English batsman, her namesake, Peter May. If only she and her party could deploy some of his flair – the despairers would not yet know what “despair” means.