Prana is usually translated as life force and is often loosely equated with breath, but the classical scheme divides it into five vayus, each with a location, a direction of movement and a specific function. Prana proper governs intake and moves inward, seated in the chest. Apana governs elimination and moves downward, seated below the navel. Samana governs assimilation and moves laterally, seated at the navel. Udana governs upward movement, speech and growth, seated in the throat. Vyana pervades the whole body and governs circulation and coordination.
The divisions track observable functions rather than being decorative. Anything taken in, whether air, food or impression, is prana. Anything expelled, whether breath, waste or an unwanted thought, is apana. Digestion in the broadest sense, including the digestion of experience, is samana. Speech, effort and the upward pull of aspiration are udana. The distributed sense of the body as a coordinated whole is vyana. Disorders are diagnosed in these terms, so chronic constipation and chronic anxiety are both read as apana failing to move downward properly.
This is also why pranayama is treated as more than breathing exercise. Different techniques are directed at different vayus: retention after inhalation works on prana, retention after exhalation on apana, and the classical descriptions of kundalini rising involve prana and apana being brought to meet rather than simply breathing deeply. Understanding which function is disturbed determines which technique applies, which is a level of precision that the general advice to breathe deeply loses entirely. The wind that governs all of this is the same principle personified as Vayu.
The five pranas turn breath from a single activity into an instrument with five settings. To see the deity who governs the principle behind them, explore more of The Living Sanatan Timeline.
Part 84 of 100 — Series II: To the Eternal
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