It is all a matter of professional perspective.
When I worked for the Forest Service Foresters were advocating reducing the timber harvest TODAY so we would not have to reduce the harvest levels TWO HUNDRED AND FIFTY YEARS from today.
The Economists, on the other hand, just shrugged their shoulders and said the "discount rate takes care of future generations". If you took economics in college it is a pretty funny comment....otherwise just trust me and laugh.
I guess I still go back to Aldo Leopold and his comments in Sand County Almanac. One of which is that you keep all the pieces in the ecosystem at some sort of level. Aldo was a Forester by education.