Right livelihood has ceased to be a purely personal matter. It is our collective karma. Suppose I am a schoolteacher and I believe that nurturing love and understanding in children is a beautiful occupation. I would object if someone were to ask me to stop teaching and become, for example, a butcher. But when I meditate on the interrelatedness of all things, I can see that the butcher is not the only person responsible for killing animals. He does his work for all of us who eat meat. We are co-responsible for his act of killing. We may think the butcher's livelihood is wrong and ours is right, but if we didn't eat meat, he wouldn't have to kill, or he would kill less. Right livelihood is a collective matter. The livelihood of each person affects us all, and vice versa. The butcher's children may benefit from my teaching, while my children, because they eat meat, share some responsibility for the butcher's livelihood.
~ Thich Nhat Hanh, in Claude Whitmyer's Mindfulness and Meaningful Work