Scientists have protested that their work on climate change is based on hard evidence. Believers, led by Daniel Johnson writing in the Daily Mail, have complained that there can be no comparison between the ephemeral role of a political ideology like environmentalism and Christianity.

I believe that both scientists and people of faith are wrong to challenge this judgement. Scientists who object to the judge’s decision do so because they regard religious beliefs as unsupported by hard evidence or rational arguments. Christians will see this as a caricature of their faith. For them religious commitment is backed by a whole range of rational warrants from historical claims about the New Testament to complex philosophical arguments about the existence of God.

The judge, however, was wrong in labelling belief in climate change as religious because it is only ‘based on the present state of evidence available’. All science is based on such evidence. Scientists do not claim to be infallible; they are all, in principle, ready to modify conclusions in the light of new evidence though in practice they do not expect many of their conclusions to be ever challenged. In the same way religious believers do not expect new developments to overturn their faith but they concede change is possible and, in the case of some individuals, it does happen.

What makes environmentalism a religion for some people is that it provides them with both a frightening eschatology that is apocalyptic on a biblical scale, and a framework for daily living. In the case of a zealous core overcoming the threat of climate change is now the main purpose of life; everything else is judge in relationship to this aim. Other concerns seem trivial by comparison.

No measure, however small, however inconvenient, or however minimal its contribution to the overall objective must be neglected. Most of us find good use for old plastic bags in containing rubbish or books for donation to Oxfam. In Dublin sales of bin liners shot up when plastic bags were banned. But none of this deters the true believers. Banning plastic bags is a symbolic action designed to increase our commitment and strengthen our faith. It is a constant reminder of the kind of attitudes we need to foster, a spiritual discipline like fasting in Lent.

But to concede that environmental beliefs can be held with religious passion and even take the place of conventional religion in the lives of some should not threaten the position of long-established faiths. In some ways it can help Christians defend their role in a secular society.

Recent years have seen attempts to ban religious arguments from public debate. Partly this is a response to the rise of the Religious Right. No one worried when Martin Luther King used religious arguments. Partly, too, it is a response to the spread of multiculturalism and a fear that religious arguments are divisive and provoke conflict. Richard Rorty famously labelled them a ‘conversation stopper’. Non-believers cannot be expected to engage with religious arguments, he maintained; it is the job of believers to express their views in neutral, public reason.

In fact, there is no such thing as neutral, public reason. We all argue from certain presuppositions and within a certain tradition. As we debate with others, our traditions may be modified or even overturned but we cannot leave them behind when we enter the debate. They are part of who we are and how we think. Banning religious arguments from the public square can itself be a divisive measure. It can leave religious believers living in a ghetto where some of their core values and opinions are never challenged by others. Worse of all, it can breed a festering resentment, a sense on the part of believers that they are marginalised and despised which can turn them to fundamentalism or even religious terrorism.

For years some of us have been arguing that it is hypocritical to ban conventional religious arguments from the public square when what might be termed ‘New Age’ arguments are advanced all the time. The proposed European Constitution was not allowed to mention God but the Swiss constitution requires ‘respect’ for the integrity of creation and ‘for living nature as a whole’ prompting one American philosopher (who is an atheist) to ask whether opposition to biotechnology is religious.

He concludes that it is not easy to say where science ends and ‘religion’ begins. Mother Earth worship, a Romantic idealisation of nature, irrational fears about public health, hostility to ‘big business’, and genuine scientific concerns are all mixed up together, sometimes in the same person. ‘Anti-biotech’, Austin Dacey writes in his book The Secular Conscience ‘is a complex mix of factual reasons and non-traditional, post-Christian spirituality and the parties to the debate disagree on where one ends and the other begins’.

The right conclusion to draw from the Nicholson case is that we do not in fact live in secular society. We live in a world where religious belief of one kind or another widespread but usually unrecognised.