Mitakuye Oyasin is Lakota Sioux for (roughly) "we are all related". It refers to the view of all things in the Natural world being interconnect. The energy flow between everything (plants, people, animals, Earth herself, etc.) as well as the great Circle of living and dying in ecological terms.
There is a great similarity between Mitakuye Oyasin as a conscious awareness, and some of the great legends of the old world empires. The web of creation found in many mythos is a cosmic expression of this awareness.
If you live according to Mitakuye Oyasin, see and experience it daily, most often you will find that it leads to a better life of health and happiness.
This has been my experience.