Just as the sun gives us warmth and vitamin D, the Earth underfoot gives us food and water, a surface to walk, sit, stand, play, and build on, and something you never, ever thought about—an eternal, natural, and gentle energy. Think of it perhaps as vitamin G—G for ground. What does that mean to you? Maybe the difference between feeling good and not so good, of having little or a lot of energy, or sleeping well or not so well. You can’t see the Earth’s energy but some people can feel it as a warm, tingling, and pleasant sensation when they are out walking barefoot along the water’s edge at the beach or on a stretch of dew-moistened grass.