Traditional Chinese medicine is based on the philosophical concept that
the human body is a system of systems. These
separate yet interconnected sub-systems usually work in balance to maintain
the body's healthy functioning. The balance of yin and yang
is considered with respect to qi ("life force", or
"spiritual energy"), blood, jing ("kidney essence"),
other bodily fluids, the Wu Xing (diagram left), emotions, and
the soul or spirit (shen). TCM has a unique model of the body,
notably: the meridian system. Unlike the Western anatomical model which
divides the physical body into individual parts, the Chinese model is
more concerned with function. For example, the TCM "spleen"
is not a specific bodily organ, but an aspect of function related to
transformation and transportation within the body, and of the mental
functions of thinking and studying.