Although I like to think I am a rational person who can consider most issues objectively, I know this is rubbish. I am biased, prejudiced, and a prisoner of my experience, although perhaps acknowledging this is better than denying it. Not easy, as the ability to deny is probably our most powerful coping mechanism, and extremely useful for people like doctors who spend much of their working lives dealing with constant uncertainty, suffering, and stress. There is only so much reality with which the human frame can cope, and many people do appear to be very skilled (maybe too skilled) at detachment, denialism, and clever ways of dealing with more than their fair share of pain, suffering, and death. Perhaps this explains why we sometimes seem so poor at understanding the effect of our behaviour and actions (or lack of them) on others.

It is the exception, not the rule, that doctors become visibly and collectively very engaged about the future. And although almost everyone finds it difficult to make much sense of the future, we might consider health professionals to have a particular responsibility and opportunity to wave the flag on behalf of the health and wellbeing of our children. This is very apparent in our ambivalence to take visible and collective action towards what the evidence now confirms is almost undoubtedly the largest health threat of the 21st century: namely our unsustainable behaviours and lifestyles leading to significant and well understood health threats. These range from obesity and global inequalities, to runaway and irreversible climate change (and the civil and health threats to everyone that will ensue). Ignorance is no excuse: health professionals know how to take a visible stand against global challenges to health. Witness the collective and vocal stand against other health threats from cholera to tobacco to nuclear war.

I have just been reading a book called Engaging with Climate Change lent to me by Caroline Jessel, a wonderful colleague from Kent.  It’s written by a group of psychoanalysts, so much of it is beyond me, but it does have a very good section on denial, particularly its different forms. The most dangerous sort is not the one concerned with active and malicious misinformation for ideological or commercial reasons (“denialism”), nor the sort, as in grief, where we initially wish to disbelieve the truth (“negation”). The most worrying form (“disavowal”) is when we casually accept the best estimates of the truth, but skilfully justify actions that avoid its obvious implications. So many doctors rightly claim that they don’t have time to address the health of the environment as they are too busy dealing with the health of their patients. Perfectly true, but it does sound a little like the person who needs to spends all their time rescuing people from the river so that they don’t have time to go upstream and stop them falling in. Pragmatism or disavowal or both?

I was reminded of this whilst listening to some guru on the radio saying that self doubt is important, natural, and mostly good as long as it does not become crippling and provoke paralysis or worst. I like the definition of a professional as someone who is constantly worried (but not paralysed) by the chance that one day they will be rumbled—something we should all be alert to, and perhaps something that medical revalidation is there to address. But remember that the sins of omission can be far more damaging than the sins of commission. When the history books are written about the 21st century (if there is anyone left to do this), it may be that the most vocal, respected, and influential parts of civic society in the early part of the century (us, now) will be rumbled, for knowing so much and doing so little.

If you haven’t done so already, you can pledge to take more action, by visiting the Climate and Health Council at an international organisation of health professionals and others dedicated to combating climate change and its impacts on health and wellbeing.

David Pencheon is a UK trained public health doctor and is currently director of the NHS Sustainable Development Unit (England).