The second leg is your relationship with all in the world that’s not human. If you have only these two legs, you can try to live a good life, but it’s like walking on stilts. The third leg is what gives you a place to rest, and that leg is your relationship with the unseen world, everything not described by the other two. Having all three constitutes health. That’s where it lives. This tripod sustains you. You don’t exist as an individual without these relationships.