What’s the point of the Liberal Democrats? Maybe the party should just shut up and die. There is a coherent and enticing argument which says that a party formed through an alliance of parties in the heyday of Thatcherism has outlived its purpose, and whose existence is harming the very cause it was founded to champion. Such an argument might go on to say, very plausibly, that British liberalism is in a pretty good state: it’s just embedded within mainstream opinion, widely adopted by both Labour and the Tories, and has no need of a party whose name recognises it.

Social liberalism marches on: witness the passing, from a Conservative Prime Minister, of legislation recognising gay marriage. Economic liberalism rules in the Treasury: from Thatcher to Osborne, and despite a Brownite interregnum, those who believe in a smaller, smarter state that promotes prosperity for all have won the argument.

Finally this argument would say, again with a great deal of emphatic evidence to support it, that the experience of coalition for the Lib Dems – in which they endured five years of misery at the polls, achieved considerable wins in government, got no credit for them whatsoever, and were slaughtered in a national plebiscite – would suggest that the fate of minority parties in government is always grim, and that the comfort of opposition is preferable to the compromises of power.

This argument has logic, recent experience, and the weight of history behind it. Despite all that, it is wrong. There is indeed a real purpose and point to the Liberal Democrats, and Britain would be weaker without them. Moreover, there is still a unique and distinctively liberal agenda which neither Labour nor the Tories have the courage to implement. This newspaper doesn’t have a vote in the postal ballot currently with party members, but for those reasons, if we did, we would cast our vote for Tim Farron.

That is not to denigrate Norman Lamb. As this editorial column observed recently, Mr Lamb is an authentic liberal with an impressive record in government. He achieved vital wins for mental health patients, and was recognised by his Tory partners as an outstandingly effective minister. He has also run a mostly strong campaign, and embraced commendable positions on, for instance, reform of drug laws.

It is the nature of the task ahead, however, that recommends Mr Farron for the role. The Liberal Democrats are starting from a very low base, and will probably take a decade at least to recover genuine parliamentary influence. Mr Farron’s suggestion that they rule out entering coalition unless they have guaranteed electoral reform would help mitigate some of the damage of any such arrangement.

Precisely because he is untainted by the tuition fees mess, and because he is a highly effective campaigner, the party’s former president has the better chance of galvanising the base and persuading voters that the Liberal Democrats offer something unique. That should include radical policies on building houses, decriminalising drugs, shifting the burden of taxation, more effective justice, and a greener economy. In all these areas, there is a vacancy.

Mr Lamb has highlighted Mr Farron’s faith, saying it led him to positions on gay marriage, abortion, and assisted suicide which are illiberal. It will be for Mr Farron to make clear to party members, the public at large, and this newspaper, that his faith can indeed be reconciled with a liberal view on matters of birth, marriage and death.