ABSTRACT
What is qi? Etymologically, the Chinese character for qi, in the form found in Zhou oracle inscriptions, symbolizes the cloudy vapors one observes in the air. Hence we can speak of yuanqi (cloud-vapor) or yueqi (cloudy vapor around the moon) in reference to observed phenomena of nature. In the present ideogram, qi suggests vapors rising from rice paddies, and hence a term dating from the agricultural period of early China. The commonly used term kongqi (air in empty space) is perhaps more recent, suggesting an understanding that in what seems to be empty space, invisible air is present. This suggests that qi can be invisible, even though it must in some way be experienced as physically real. Huoqi (fire-vapor) could refer to something other than the visible wave of heat when something is burning: that is, to the sensation of heat (reqi) and the underlying cause, which is described as a qi “of the fire type.” In this sense qi is no longer observable but is still a potent agent, causing the combustion of wood and the emission of heat. The human body receives evidence of huoqi as a physical sensation, experiencing a change when heat is conveyed to it.
