Axel Gosseries wrote:
>I was wondering what the main reason would be why Sidgwick did not see 
>that improvements to climate could actually be sold (through a tradable 
>quotas scheme). Any suggestions?


Axel: who would buy such improvements in the absence of government 
requirements that the climate be  undegraded? Tradable quotas today occur 
in the context of  restrictions on emissions put in place by governments 
and enforced.  Without such restrictions, the benefits are not appropriable 
- just as Sidgwick says. A better climate is a public good which is subject 
to free-riding. If one of us gets it, all of us do - it is impossible to 
exclude non-payers. Each of us does better not paying for it no matter what 
the others do, so no one pays and the entrepreneur attempting to sell the 
improvement fails.

Kevin Quinn