James Hansen is arguably the most famous and brave climate scientist living today. He was asked to give evidence on behalf of a group of protesters who had broken into a coal-fired power plant in Britain and caused $70,000 worth of damage; the six activists did not deny what they did. “The not-guilty verdict, delivered after two days and greeted with cheers in the courtroom, raises the stakes for the most pressing issue on Britain’s green agenda and could encourage further direct action. The defense of “lawful excuse” under the Criminal Damage Act 1971 allows damage to be caused to property to prevent even greater damage. ” (The Independent, September 11)

“Think like a [person] of action, act like a [person] of thought.” Henri Bergson
The verdict has huge implications for Britain and the world: nations must defend people who protest and act to stop climate change destruction. The jury of twelve thought that a greater crime was being committed by the coal plant with its release of greenhouse gases, and they released the activists.
This brings us to the Precautionary Principle. Interestingly, the Precautionary Principle is found on Environment Canada’s website  www.ec.gc.ca See ‘A Canadian Perspective on the Precautionary/Approach Principle Discussion Document’ that states “Canada supports the statement in Principle 15 of the 1992 Rio Declaration on Environment and Development: “In order to protect the environment, the precautionary approach shall be widely applied by States according to their capability. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradationt.”
In the case of climate change it would be hard to find any scientist in 2008 that has not accepted that climate change is real and that humans have caused it. Aside from that fact, nothing we do in life has 100 percent certainty, and we apply the precautionary principle all the time. ‘Better safe than sorry’ or ‘Err on the side of caution’ are just two of many aphorisms that sum up our daily walk through life. We can’t afford to be cavalier about climate change!
Medicine is no different.  ’First, do no harm’ can be seen as the precursor of the Precautionary Principle. We can do irreversible harm by not taking action. Clearly the Precautionary Principle, as applied to the planet and medicine, means that we are proactive. In an interview this week with Dr. Ralph Manktelow, a surgeon, it became plain that doctors frequently act without complete knowledge. The best research efforts that are meant to be the foundation for a doctor’s actions can be found to be inconclusive; this does not mean that a doctor refuses to operate when his patient can face a worse fate through inaction.
Regarding such issues as public health and food safety, few would dispute how important precaution is, but the same principle has not been applied to climate change. Why? Is it that governments and people feel that climate change is still far off in the future? Does anyone truly believe that it is not the duty of every adult to do what is required to stop climate change, considering the fate of future generations?   What has been happening in the arctic this summer would demand that the future is now: in the last 100,000 years never before has (liquid) water completely surrounded the North Pole.
There is no doubt that Canada and its provinces have not lived up to the Precautionary Principle as it is stated in the Rio Declaration. We all must be held accountable. ‘Aspirational targets’ have no place in any government’s fight to stop climate change. Such targets are utterly jejune..