Free-market economics seeks to equate marginal social cost and marginal social benefit for the purpose of deriving the optimal level of environmental damage. 

Economists in favor of this system would argue that it finds the level of destruction of the environment that maximizes human well being.  However, this is not the only method of determining what amount of environmental destruction is in the best interests of society.

David Pearce suggested a similar but unique method of finding the optimal pollution level.  He argued that in harming the environment, people decrease its ability to be damaged further, a theory that is scientifically supported.  For example, in filling the environment with waste beyond the level that it can handle, the environment's ability to assimilate waste is decreased.

Pearce argues that the consequences of damaging the environment are essential to economic evaluation.  These consequences are taken into account in Pearce's analysis.  He argues for an "ecologically stable output" level, a point where the environment's assimilative ability is not decreased.

Some have argued that the level Pearce advocates is zero pollution.  They feel that this is overly restrictive, and not in society's interests.

A large degree of uncertainty surrounds any method of determining the optimal level of pollution.  It is impossible to fully predict the negative impacts of some actions such as dumping radioactive waste, which leads some people to say that this should not be done to any degree.