Yīn and yáng are divisible but inseparable

The principle that although all phenomena can be divided into yīn and yáng, and each yīn or yáng phenomenon can be divided into yīn and yáng aspects, either phenomena of a pair that stands in a mutually dependent yīn-yáng relationship cannot be separated from the other without the loss of both. Division here means a cognitive distinction, whereas separation is the actual parting of the two. Yīn and yáng can be divided ad infinitum. For example, whereas motion is yáng and stasis is yīn, within motion there is a distinction between upward motion, which is yángand downward motion, which is yīn. Upward motion is yáng within yáng, whereas downward motion is yīn within yáng. However, though yīn and yáng can be differentiated in this way, they cannot be separated: the two are always interdependent and therefore inseparable; one cannot exist without the other. See yīn and yáng.