It would be much more credible if vegetarians said, for instance, that the suffering of animals, health benefits, environmental impacts, and purely spiritual concerns all involved considerations that pointed both towards and away from vegetarianism but that the balance of the arguments points towards it.
In practice, as far as I can tell, environmental concerns pretty much all point towards vegetarianism with some shellfish and other abundant sea life.
It would be much more credible if vegetarians said, for instance, that the suffering of animals, health benefits, environmental impacts, and purely spiritual concerns all involved considerations that pointed both towards and away from vegetarianism but that the balance of the arguments points towards it.
In practice, as far as I can tell, environmental concerns pretty much all point towards vegetarianism with some shellfish and other abundant sea life.