What are "natural risk levels"?

Natural risk levels are those limits of potentially high-stakes (i.e., catastrophic) risks which maintain a parity, or balance, with respect to naturally occurring risks. Society's risk management charge must be to accept no human-induced risks that significantly alter these levels.

It is often argued that there can be no progress without incurring commensurate risk. In fact, true progress is measured by how far we can get beyond mere subsistence, safely. 

For additional insights on natural risk levels, and their achievement, click here.