In martial arts, the medium is the activity of arriving obstacles. Without obstacle, there is no martial art, and there is no martial way. The wisdom of aiki is whereby through wisdom, awareness, perception, love, and compassion, all aspects better in the meeting, in each and every contact, though there be even a great turbulence or a great peace.
Therefore, it has been said that, there is no practice without four hands. This is true, and when one finds the hands of the will of kami, then one can practice anywhere, until then, four conventional hands are required.