[WS:] It is a good principle, but as any principle it is not absolute.
What if there is a product or treatment that addresses some existing problem now, say a terminal illness, but long term consequences are unknown and will not be known for years to come. What is the right course of action when you face the dilemma of addressing a known problem now and risking unknown consequences in the future, or avoid unknown risk in the future but fail to address a known problem now?
Behavioral economics (Daniel Kahneman) tells us that the solution to this dilemma is subject to cognitive bias. If you state the problem in terms of risk e.g. X number of people may die in the future, most people would chose the precautionary principle, but if you state it in terms of benefits e.g Y number of people can be saved now, most people would reject the precautionary principle.
This means that business interests should be prohibited by any means necessary from defining the terms of the debate on these issues because they invariably will define it in terms that will use cognitive bias to their advantage. This calls for strong and independent regulatory agencies - not ones that are in the pockets of business interests.
-- Wojtek
"An anarchist is a neoliberal without money."