The Department for Education in England recently issued guidance to teachers to remind them of legal requirements to be politically impartial when they teach sensitive topics such as the legacy of the British Empire.

Commenting on the guidance, Education Secretary Nadhim Zahawi said “contested theories and opinions must not be presented to young people as facts”. He added that an important purpose of the guidance is to ensure that “children can learn about political issues and begin to form their own independent opinions, without being influenced by the personal views of those teaching them”.

It’s hard to see that Zahawi’s reminder of the need for teaching to be politically impartial should be at all contentious. To become citizens in a democracy, young people must be taught how to think rather than what to think.

Yet Zahawi’s comments were greeted with protest. Mary Bousted, joint general secretary of the National Education Union claimed the guidance would make teachers reluctant to teach controversial topics. Rowena Seabrook, an education spokesperson for Amnesty International UK claimed that the guidance would “have a chilling effect in classrooms”.

While the spirit of the guidelines ought to be uncontroversial, the line between a fact and a contested idea is not always straightforward to draw. The progress of science teaches us that many theories once thought incontrovertibly true – for example, that the earth is at the centre of the universe – were eventually overturned by new evidence. Even ideas that seem unlikely to be refuted scientifically such as evolution are contested by some.

Of course, evolution is a scientific idea, whereas Zahawi’s guidelines are meant to apply to the teaching of political topics. Political ideas are often more emotively contentious than scientific ones, perhaps because political viewpoints can depend more on values than on evidence.

It is unclear whether New Zealand has a problem in its education system that guidelines like Zahawi’s would fix. What is clear though, is that it’s becoming increasingly difficult to discuss contentious topics openly. To present a viewpoint at odds with those fashionable can draw opprobrium, censure and even ostracism. Examples include vaccine mandates, the constitutional role of the Treaty of Waitangi, the uncertainties inherent in climate change modelling and how mātauranga Māori should be positioned in relation to science in the New Zealand Curriculum. Yet these need to be discussed in a frank and open way for the good of our country.

In a democracy, political ideas must not only be contestable but must actually be contested. For democracy to remain healthy, diverse viewpoints must be included and welcomed in public debate.

This brings us back to the importance of teaching students how, rather than what, to think. But how might teachers go about teaching children to think for themselves? One answer is that, rather than drawing a sharp distinction between facts and contested ideas, we should focus on enabling children to contest ideas productively – that is, in ways that lead to better ideas.

To argue productively, students do need to be taught facts – the body of established knowledge relevant to an argument. Without that, they’re flying blind. And when teaching the facts relevant to a political debate, teachers do need to be aware of their own opinions and avoid cherry-picking facts that support them while ignoring those that challenge them. Students also need to be taught to reason – that is, to argue logically and to avoid fallacious statements.

In political discourse, the ability to make a sound argument is necessary, but it isn’t, on its own, enough to make a strong contribution to political debate. Certain dispositions are also important. Perhaps foremost amongst these is humility.

Humility entails assuming that there’s something to learn from those we disagree with. It means being open-minded and willing to alter our opinions in the light of new information. It is a quality that seems to be lacking in much of our current political discourse. Adopting a humbler stance when contesting ideas would do much to counteract our increasingly censorious and polarised political culture.

Intellectual humility needs to be modelled rather than taught explicitly. If children observe adults practising respectful, attentive and open-minded disagreement, they’re more likely to adopt that way of arguing themselves.

In a democracy, argument has a higher purpose than humiliating our opponents. That kind of argument does nothing to improve our ideas. If instead, we argue in good faith, we can discover things that we would not or could not have discovered alone. Facts, reason, humility and respect are the best guidelines for teachers interested in preserving and enhancing democracy.