The contest to be the next leader of the Conservative party, which has six entrants and will last until November, by necessity involves a great deal of reflection. It could hardly be any other way, in the wake of the party’s worst defeat in its 200-year history: every aspirant is right to understand that there can be no realistic hope of recovery without understanding how Conservatives came to such a calamitous and precipitous failure.

One of the most common themes, which was being thrown around well before the general election, is that the party has lost its ideological moorings, abandoned fundamental principles and embraced instead a fatal combination of managerialism and incompetence. There is, as the 4 July election proved decisively, little support for technocrats who cannot even achieve the tasks in front of them. But an idea which is commonplace now, and will be insidious and toxic if it is left unchecked, is the proposition that the successful candidate must be a ‘proper Conservative’ and so re-embrace the party’s ‘real Conservative’ beliefs.

The candidates themselves have been careful not to enunciate this notion explicitly but their supporters and proxies have done so freely. Sir Edward Leigh, veteran MP for Gainsborough who is now backing Robert Jenrick, told journalists after the first meeting of the 1922 Committee last month that his party needed to become a ‘proper Conservative party’ to win back Reform UK voters. Lord Frost has joined Team Jenrick similarly because he regards the former immigration minister as having ‘genuinely conservative’ principles. Meanwhile, Sir Jake Berry, a former party chairman, has thrown his weight behind Tom Tugendhat because he is a ‘proper Conservative’, while GB News’s Mark Dolan has cried out for ‘some proper conservative candidates’.

This fixation with ‘proper Conservatism’ manages to be simultaneously meaningless and noxious. It is dangerously divisive because of its implication: if the candidate you support is a ‘proper Conservative’, then he or she is heir to the party’s greatest successes and heroes. And by extension, inevitably, the other candidates are somehow ersatz or insincere, or at least misguided. They are not ‘proper Conservatives’.

This is the language of religion, of the sect and the schismatic. The faithful have wavered, the faith itself has become weak, and we must turn for salvation to the truly sincere, those who still adhere to the fundamental verities. It is an excellent recipe for stoking division and promoting not just distrust but contempt. Worse than that, though, it is built on a raft of incoherence.

What is ‘proper Conservatism’? Perhaps it is adherence to the manifesto which won the 2019 general election, when the party was led by Boris Johnson. This was a platform which emphasised substantial spending on the National Health Service and other parts of the public sector, which talked relatively little about taxation and which emphasised the goal of achieving net zero carbon emissions by 2050.

If that seems dubiously ‘Conservative’, perhaps we should look at the party when David Cameron won a majority in 2015. Having parted company with his Liberal Democrat coalition partners, Cameron expressed the need for government to run a surplus (by 2018, the manifesto hoped) but also stressed the pressing urgency of infrastructure investment – funded by taxpayers’ money, of course – and made great play of the northern powerhouse.

Perhaps contemporary MPs and activists are uncomfortable with a Cameroon platform. The last manifesto to win an election before 2015, then, was that of John Major in 1992. That document dedicated a great deal of energy to reform of the public sector and the Citizens’ Charter, but it also pledged higher spending on the NHS and crammed in hasty promises on privatisation.

Instead of trying to distinguish truth from heresy, each of the six candidates must be allowed to articulate Conservative principles as they see them. They should then explain how these principles will create a better and more prosperous society. And they should make clear how they will take advantage of the missteps of the Labour government – missteps which are already coming with surprising speed and abundance. MPs will whittle the half-dozen hopefuls down to two. The party membership will then choose between them, and that must be an end of it, for the foreseeable future.

Successful political parties can never achieve absolute ideological purity, because politics is not an intellectual game but an exercise in persuasion and governance. This is especially true of the Conservative and Unionist party, which has no single foundational text, a Das Kapital or Little Red Book. Unless you are willing to espouse with exacting adherence every principle in Sir Robert Peel’s Tamworth Manifesto (the 1834 election address which is generally held to mark the birth of modern Conservatism), you have to adapt to contemporary circumstances – that is what politicians do.

Enough of ‘proper’ and ‘real’ Conservatives: focus instead on whichever candidate can produce a coherent platform which centre-right voters will gradually gravitate to. To do otherwise is to cultivate division and embark on a destructive cosplay of the Labour party in the 1980s, where everyone was seen as either a comrade or a traitor.