Group polarization is a term well known to psychologists but little known outside their field of study. Yet it may prove to have particular significance during the climate change conference in Copenhagen.
Group polarization describes what happens when people of strong views on any subject come together and discuss them. Almost invariably, the views of each individual member become more potent or even extreme; convictions become more entrenched and conclusions less open to question.
It is, if you like, a form of 'herd instinct', a powerful expression of social conditioning, and events of the past few days suggest that eminent scientists are as susceptible to group polarization as the rest of us.
A small storm erupted late last week with the release on the internet of the pirated e-mail correspondence of one of science's most respected advocates of climate warming.
Professor Phil Jones is director of the climatic research unit at the University of East Anglia in Norwich. His team's databases recording global temperature changes have played a central role in building the case for global warming -- and, by extension, humanity's responsibility to reduce carbon emissions.
The e-mails in question seem to suggest that statistical trickery may have been used in an effort to shade data in support of a cause, rather than producing accurate science. It is alleged that in at least one email to a colleague in America the professor even proposed organising boycotts against scientific journals which published papers challenging the warming message.
If this is true, the people involved have crossed the line between publishing science and promoting propaganda. The public is left asking: is this the only time this has happened in the global warming debate? Are other science units making similar decisions, on both sides of the argument?
It is entirely possible that opponents of global warming have held onto the hacked emails until now so as to create maximum doubt prior to the Copenhagen summit. But that should not distract us from the importance of what this story potentially represents.
There are two things that make this story both compelling and unsettling. First of all, it reminds us that science is not merely about the production of information.
Contrary to a widely held impression, scientists do not simply observe and record data or 'facts'; they also make assumptions about those facts. And being as human as the rest of us, they are just as prone to being influenced in these assumptions by professional pride, career ambition and even financial gain.
There's no evidence of any financial motive in this particular case. Yet we are left to wonder why at least one eminent climatologist may have chosen to highlight certain interpretations of fact over others. Was it in an attempt to promote or protect his unit's importance? This would be all-too-human, but hardly helpful to a debate as important as this.
Over the past few days it has also emerged that the raw data on which the unit's important findings were based are no longer available. Supposedly this is because they were collected before the widespread digitization of information on computers.
So, the only data now available for further scrutiny takes the form of 'value-added' information - that is, data which has already been adjusted or interpreted in some way. Meanwhile, requests for the raw data - some made by respected academics - have been consistently denied, apparently without anyone thinking to mention that it no longer existed.
The advancement of science relies on a capacity to access raw data, so that it can be tested and re-evaluated by other scientists. This allows for the development of alternative interpretations and hypotheses, for debate and synthesis which leads to new paradigms.
Without this kind of accountability and transparency, science becomes a form of secular religion; with scientists scoffing at the subjectivity of other forms of belief while expecting that they will receive a kind of priestly deference.
There's a second reason why this story is so important. In it we may be seeing an emerging differentiation between globalisation and 'globalism'.
The former represents the dropping of barriers to world trade and migration. The latter, though, may refer to a new kind of worldwide 'we-think', in which conclusions on important issues are arrived at quickly and disseminated to vast numbers of people without allowing proper time for reflection or proper opportunities for debate.
Globalism of this kind might lead to group polarization on a grand scale.
Scientists who no longer care to, or are able to, question one another's assumptions, may simply bolster the prejudices of the majority. Meetings of government leaders may merely strengthen already-held views, instead of asking difficult questions in a quest for truth.
When group polarization operates at a local level it can lead, for example, to discrimination against ethnic minorities. At a national level, it can spark bloody revolution or the rise of fascism. But on the global scale, it may result in government leaders committing entire populations to extreme actions which are based more on emotion than logic.
Although hopes of any binding treaty emerging from Copenhagen have been diluted in recent months, measures still on the table will potentially impact thousands of industries and many millions of individuals globally. They may also pass heavy responsibilities to our children and grand-children.
So, we the voters and our elected leaders need to know that the science available is more than speculative.
Scientists cannot be permitted to lob hard predictions into the public debate then retreat to the safety of their research labs when asked to support them.
If the 'facts' on which they rely lack an authority which is both transparent and tested, the debate itself may also distract them from what might turn out to be more pressing issues.
For example, we may wonder as we approach 2010 what has happened to the idea of making poverty history? Who is keeping the UN accountable for its Millennium Development Goals, set in 2000?
What is happening about the global fight against HIV/AIDS and other pandemic diseases; or the reduction of warfare worldwide; or people trafficking? These and many other issues cry out for international debate at a high level.
One can be wary of climate change predictions without being anti-environment. The earth's often fragile ecology should be of concern to us all, in the interests of our own survival if nothing else. If even a small percentage of the tumultuous events some climatologists predict are likely to happen, we must pay urgent attention to the warming issue.
However, if the debate is driven by politics hiding behind a mask of science, or if it is driven by data that's not open to evaluation or by assumptions that are not properly scrutinized, we may need to step back, take a deep breath and respond in a more measured way.