Democratic Alliance insiders have long identified a serious threat to our project: the proliferation of DA members whose own values are fundamentally at odds with the party.

We must be wary of those who see the DA merely as a platform for publicity or a path to power. There is no point winning elections if we cannot implement a programme of action grounded in our vision of an open, opportunity society for all.

At the same time we must be aware of those who use the spectre of ‘illiberal tendencies' to shut down legitimate debate and discredit people. Such bullying tactics are the hallmark of authoritarianism, not liberalism.

Alan Paton once described liberalism as "a generosity of spirit, a tolerance of others, an attempt to comprehend otherness..." His point was that, besides a commitment to the rule of law and individual freedom, liberalism is about empathy, mutual respect and the ability to see other people's points of view.

For liberals, this means dispensing with the dogma and grappling with some of the great questions we face, such as: what does it mean to be a liberal in Africa? Is there a place for notions of community within the liberal framework? Are liberalism and religion compatible? The list is endless.

The DA's National Spokesperson Mmusi Maimane attempted to tackle one such question in an opinion piece published in the Sunday Times this week. In it, he interrogated the concept of ‘Africanness' and its place in our democratic discourse following Jackson Mthembu's attack on Lindiwe Mazibuko.

Maimane argued that nobody has the right to unilaterally decide or prescribe what is or what isn't African. Furthermore, traditions and cultures are constantly evolving and, as such, are open to the interpretation of each individual.

Maimane went on to say that his identity as an African comes from a sense of shared history and an emotional connection to the continent. He argued that, for him, the idea of Ubuntu sums up his Africanness and that, in his view, being African means being part of a community.

That is how Mmusi Maimane chooses to self-identify as an African. He was not forcing his identity on anybody else; he was stating what Africanness means to him.

When Barack Obama talks about something "inherent in the American spirit", nobody accuses him of being illiberal. Likewise, when Nick Clegg talks of inculcating an inclusive, positive British identity, his liberal credentials are not questioned.

And yet a former DA staffer suggested in his blog yesterday that Maimane's column signalled the erosion of the DA's liberal values on the grounds that:

1. Maimane suggested there was such a uniform thing as ‘Africanness'

2. There is no such thing as Ubuntu and, if there was, it would be anathema to liberalism

3.  There is no such thing as community, that it is an artificial abstraction incompatible with liberalism

The first argument is intellectually dubious because Maimane explicitly rails against uniform notions of Africanness, asking: "What right does Mthembu or anyone else have to prescribe identity to others?" Maimane's intention was to describe what Africanness means to him without being prescriptive. To suggest otherwise is dishonest.

The second argument is worth having. It is true that the concept of Ubuntu is ill-defined. But, because of this, it is difficult to ascertain whether it is compatible with liberalism or not. Since both concepts are open to contestation (even if liberalism is far better defined), it is feasible for a person to self-identify as a liberal who believes in Ubuntu.

The third argument was the subject of fierce academic debate between communitarians and liberals in the 1980s. It fizzled out when somebody pointed out that one could be an individual in the context of a defined community - as long as group rights were not permitted to override individual rights.

Like Africanness, liberalism cannot be defined and prescribed by any one individual because - for one thing - it is not static. Liberalism is constantly evolving, particularly as it is applied in new contexts on our continent and across the world.

This is something that liberals should celebrate and not feel threatened by. Pluralism gives rise to debate and introspection. It brings a freshness and energy that invigorates our project.

We must guard against self-appointed custodians of liberalism unilaterally deciding what liberalism is and what it isn't, and who is in and who is out. If we do not, you can be sure that authoritarianism will follow suit.

Gavin Davis is Communications Director at the Democratic Alliance. He writes in his personal capacity. This article first appeared here.

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