Mudra is a Sanskrit word, and means both gesture and lock. The practice of yoga mudra is explained in terms of Ayurvedic medicine and Yoga philosophy. Each of fingers invokes one of five elemental substances: fire, water, air, earth, or empty space. By causing two or more of these substances to mix, the mudras are understood to create a particular medicinal - even mystical - effect. But what is really happening, if anything, and could yoga mudra practice have an established, tangible benefit, beyond the feel-good philosophy?
To better illustrate the traditional view and where it may go wrong, consider the Akash mudra, pictured here. In Yoga philosophy, meditation on Akash mudra is said to cultivate one's awareness of interbeing. In Ayurvedic medicine, touching the thumb to the middle finger represents a mixing of space and fire, and thus the mudra literally burns out impurities from the inter-cellular environment. Mystically, Akash mudra is thought to purge impurity from the whole universe, and thereby enhance our interconnection.
Similarly, Vishnu mudra is thought to help clear the energy channels within the body. The body's energy - known as chi in traditional Chinese medicine and as prana in Ayurvedic medicine - supposedly flows within us in dedicated channels, termed nadis in Sanskrit. Disturbances in the flow are thought to cause illness, and the yogi improves prana flow by alternating the airflow through the nostrils, blocking first one nostril with the thumb, and then the other with the little finger. Mystically, this practice is understood to close a "prana circuit", using the thumb to invoke fire to burn the impurities and then the little finger to invoke water to wash the channels. It is not immediately clear that nostril breath is an integral part of this process, but, traditionally, each mudra should be paired with a specific kind of breathing technique.
Now that we understand quite a lot about the traditional theory of yoga mudra, we are ready to ask, Does any of this actually work? Traditional medicines often come up short on theory, though they have established the empirical benefits of practices such as Pranyama, Shiatsu, and Acupuncture. But, they have created theories which have no logical backing, and which therefore cannot explain anything. For example they have never established a direct connection between energy meridians and the anatomy of the body. Even worse, we now know that four of the supposedly indivisible substances of Ayurvedic medicine are actually composites of simpler elements. The English chemist Joseph Priestley showed, in a series of experiments culminating in 1774, that air is composed of simpler substances, one of which he was able to isolate. Then, in 1783, the French chemist Lavoisier, pictured here, showed that water is composed of two elements, for which he coined the words hydrogen and oxygen. And, soon after - in 1777 - Lavoisier convincingly showed that fire is not a substance, but rather a process, in which oxygen combines with any one of a number of other elements. Taken together, these discoveries fatally undermined - for logically-minded thinkers - the entire theoretical basis for Yoga mudra practice. And it is thus logical to ask, Why practice?
To answer that, we turn to Zen Buddhism. From Zen we have the term, samadhi, which is translated into English as one-pointed mind. We should avoid a spiritual interpretation of this term; it is a mistake to think of samadhi as just another word for focus or oneness. It is rather to be understood as focus on an actual point in 4-dimensional space. Some Yogic traditions practice trataka, or candle-gazing. And in English we have the term omphaloskepsis, coined from Greek and usually understood ironically, as a reference to people who waste their time daydreaming. But if understood literally, both of these practices gradually develop the skill to remain focused on a point, and it is that skill which in the Zen tradition is called samadhi. And it is this power which we should seek to apply in mudra practice. Without cultivating samadhi, the mudras are nothing much more than stylistic elements. They make good marketing, but there will be no significant healing effect. But use the mudras correctly, and then you create a very powerful practice of samadhi - samadhi applied to your body. This is not a philosophy. If nothing is happening physically, if you are not feeling acutely more relaxed, if you are not experiencing powerful symptoms of physical and emotional detox - then you can be sure that you are not using samadhi, and you need to think more clearly about the mudras. Why are there are so many variations, and what are the differences between them, and how can I make this practice work? And indeed it can be made to work. It is a most phenomenal practice, so do not be discouraged, and keep thinking.
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