It will take the kind of conformism and sense of moral obligation offered by religious thought and ritual if we are to save the planet

There's a first class article in Nature this week on the reasons Americans reject the science of climate change. It has wider implications for a lot of the ways in which we think and talk about rationality.

The author, Dan Kahan, is not a scientist but a professor of both law and psychology. He is attacking the position that people reject the science of climate change because they are too stupid and too irrational. The idea that people disagree with them only because they are stupid and irrational is probably the consensus among scientists, even if you can't call it the scientific consensus because there's too much evidence to show that it is wrong.

Kahan cites some of his own research to show that the members of the lay public who are most science literate, and the most proficient at technical reasoning, are also the most divided on climate change – in other words, the deniers of climate change are among the most scientifically literate members of the general population.

This is not so much because they reckon they are smarter than the experts, but because they are able to pick the experts who agree with them: "People with different values … individualists compared to egalitarians, for example … draw different inferences from the same evidence. Present them with a PhD scientist who is a member of the US National Academy of Sciences, for example, and they will disagree on whether he really is an 'expert', depending on whether his view matches the dominant view of their cultural group."

One explanation is that we have a problem of propaganda: the lobbyist's rule that for every PhD there is an equal and opposite PhD makes it easy for malevolent forces to blind the world with bullshit.

Kahan, however, sees a rather more powerful explanation. "Positions on climate change have come to signify the kind of person one is. People whose beliefs are at odds with those of the people with whom they share their basic cultural commitments risk being labelled as weird and obnoxious in the eyes of those on whom they depend for social and financial support."

The result of these pressures are everywhere. It is not just your conclusions that your peer group influences but also your data. Both believers in and deniers of climate change find their positions vary with the most recent weather – but they disagree, sincerely, on what this weather has actually been.

Personal experience is not infinitely malleable. Perhaps if there were anything we could do about the weather, our opinions of it would be modified by the effects we saw our actions having. But there isn't. The weather is uncontrollable and this is even more true of climate change. What you or I do as individuals makes no difference to global warming. Even what the whole of the UK does won't change much.

The kind of changes in consumption needed to make a real difference to our carbon output would require multinational action at government level. But democratic governments act from perceived self-interest even more than individual voters do.

Since their actions are consistently directed to an end, an economist could call them rational. Both voters and governments, in ignoring the very painful adjustments that would be needed to diminish climate change, are definitely working to a utility function. They want to minimise their own unpopularity and will see the world in ways that make their actions seem rational. In general the right has understood this better than the left (or do I say this because the misdeeds of the other side are so much more apparent?).

Underlying all this confusion is the problem that we don't have a way of ranking rationalities, so that the word means something more to a moral agent than it does to an economist. There may be ways of fixing that and averting catastrophic global warming that don't make use of religious resources, but I can't think of any.

It's important to this argument to understand that religious resources need not be theistic. All they need do is make manifest a higher rationality than self-interest. This isn't an argument about whether God exists, but about how human beings make up their minds and form their characters. Atheist states based around myth and ritual are not hard to find. Social Democratic Sweden struck me even at the time as a theocracy organised around the worship of itself, and the official ideology was atheist. That's a benevolent example but there are plenty of malevolent atheist regimes that could serve as unpleasant examples. One of the most chilling aspects to accounts of life in North Korea is the degree to which official propaganda appeals to altruism and bravery.

What religious thought – and ritual – can supply is the two things absent from normative consumer liberalism. The first is a belief that the choice between ends is not arbitrary or wholly personal: that there are moral facts of the matter; that saving as much of humanity as possible is an obligation on all of us, and that this is actually true, and not just a matter of preference.

The second is the kind of conformism, reinforced by all kinds of social ritual, large and small, which will enforce the social discipline needed to carry societies through some pretty ghastly changes. Let's face it, any adjustment to an ecologically sustainable standard of living is going to be a lot nastier than anything Greece is going through now. It will need considerable determination and solidarity.

All of the elements necessary for this are in fact present in a rather disorganised way in the society we have now got. The basic mechanism of social conformism is not so much policing behaviour – that needs only outrage – but policing emotion: the kind of second-order enforcement of conformity where my failure to feel outrage becomes itself a matter for your outrage. There's plenty of that around today.

Similarly, I don't think our society believes there are no moral facts. On the contrary it believes that it is a moral fact that choice is the highest moral value, and so that it is wrong to maintain that other moral truths exist. Perhaps this can function as a unifying and compulsory truth if enough people believe it. It's certainly no less mythical than the alternatives.

Kahan ends his piece with a flight into pure fantasy: "Overcoming this dilemma requires collective strategies to protect the quality of the science-communication environment from the pollution of divisive cultural meanings." But the whole thrust of the piece is that there is no science communication that takes place independent of culture. You're going to have to fix the culture, so that words like "trust" and "sacrifice" mean something, before the science can in fact be communicated.