The tastefully-named Iain Dale invited a Greenpeace spokesman to debate the politics and science of global warming on 18 Doughty Street. The other “political” figure was to be eminent journalist Dominic Lawson. The enviro reply startled Iain:

We have a policy at Greenpeace that we no longer debate people who don’t accept the scientific reality of anthropogenic climate change. It’s similar to the policy undertaken by cancer specialists who used to debate the tobacco industry but discontinued doing so. To paraphrase Richard Dawkins, if we debated Dominic Lawson on climate change it would look great on his CV, not so good on ours.

As I said in my New Atlantis article on eco-censorship, denying debate achieves several objectives:

So if that’s all that the climate change denial charge can mean, why is it being made with such enthusiasm? The answer seems to be the chilling effect it has on the scientific debate. It makes public profession of opposing views unpalatable. Thus, Richard Lindzen of M.I.T. argues, “Scientists who dissent from the alarmism have seen their grant funds disappear, their work derided, and themselves libeled as industry stooges, scientific hacks, or worse. Consequently, lies about climate change gain credence even when they fly in the face of the science that supposedly is their basis.”
There is another, even more worrying result of the denial charge. It enables alarmists to portray the science as dispositive. The only way to solve the problem, science supposedly shows, is to reduce greenhouse gas emissions radically. Anyone who argues against this conclusion is deemed a denier.
Yet in public policy, science is not dispositive. Economic, political, and moral considerations also need to be taken into account. Practical tradeoffs and competing priorities need to be considered. By tarring those opposed to climate-change policy with the charge of denial, the alarmists have elided the economic, political, and moral debate to their great advantage.
Even worse, the denial charge obscures the many uncertainties that surround our understanding of climate change and its implications. Global warming is a serious enough subject that it needs to be debated fully, submitting every hypothesis to rigorous testing and hard-headed analysis. When the alarmists say the debate is over, responsible scientists and policymakers must reply, like Galileo, “And yet it moves.”

Moreover, if, like Heracleitus, we believe that justice is conflict, the denial of debate in the political sphere leads to fundamentally unjust outcomes. The fact that Greenpeace is worried about its CV (resume) simply underlines that this is all about apperences and power, not about justice, or, for that matter, science.