"Oh! Goodness you're entirely right...though I must confess I haven't much information on the exact workings of it. Hamon was the gathering of life energy- the energy of the sun itself. It concerned not only the flow of one's breath, but the flow of everything around- blood, water, anything alive and organic at all. That, at the very least, was how the hamon could affect a rock without harming the frog- and as well how it could heal! It brings life after all! ...Unfortunately I can't well explain precisely how beyond that."