Interestingly, if air were in danger of being over-breathed then privatization would be the best solution. The only reason we don't have a tragedy of the common

Interestingly, if air were in danger of being over-breathed then privatization would be the best solution. The only reason we don't have a tragedy of the commons in the air is that there's an awful lot of it and nobody has anything to gain by breathing a hundred times more.