When you relax the root softly but firmly into the Earth from a good posture, and the joints of the body remain free and open, then the energy of the Earth will gently spout up the leg and gush into the opposite side of the body. This is cross energy. It generalises into a principle that states that soft structures born of the rigours of discipline and correct practice become vessels for energy of a completely different quality and order to the energy that created the structures. The key word is softly. Softness means that my labour never resists the energies ready to manifest in the structures created by that labour, no matter how strange or difficult or unexpected those energies may be. In this sense, ignorance – lack of mindfulness – is a form of resistance.