Chinese Medicine evolved from observing people in nature and society over many thousands of years. The effects of climatic factors and emotions on physiology are understood in Chinese medicine through the relationships between internal organs and pathways of energy (qi) called channels. Palpating the radial pulse and observing the tongue color and coat are two classical diagnostic methods that allow practitioners to evaluate the inner physiology of the patient and determine how to go about enhancing the overall function of the body and mind. Additional diagnostic methods include questioning, palpating channels and tissues, and observing gait and posture.