When a bomb threat is called into a high school, the issue is not put up to a debate. Nor, does the police wait for a complete search of the building before the children are evacuated. Long before such an irresponsible call comes in, the community, the police, and the educational system institutes a specific plan to deal with a situation fraught with unknowns. There are procedures that the officials must follow to protect life, measure the importance of the threat quickly, and deal with the potential havoc. On the great environmental issues of today, we need to gather enough information that will help us decide at what point an intelligent decision can be made.
Scientists have a role in environmental decision making, but the public is the final arbitrator.
In addition, given the gravity of our environmental predicament, the error margin should be on the side of those concerned about the health of this planet. This is because once a part of Nature goes, we can never get it back. In philosophy, a common joke of the discipline is that philosophers argued about how many angels could dance on the head of a pin, while a millennia passed by with little human advancement. The same criticism can be made of a picayune obsession with scientific detail when the public cries for direction. Refuse to gain a higher perspective of the environmental problems of today, than what facts you wish to extract from an argument, and our forests will be gone.