Dantian, Ming Men and the Motive Force
Hara is the Japanese word for the abdomen. However the concept goes deeper. Hara also describes a particular area within the abdomen, the lower abdomen. The lower abdomen is host to a number of traditional Chinese concepts all of which can be referred to as residing in the space between and below the kidneys.
The area between and below the kidneys is said to store both pre and post natal Qi and Essence (Jing). Fire provided in the form of (pre-natal) Basic Qi and Qi drawn to the kidneys from the Lungs warms and moves the stored Essence to generate and circulate more Qi.