In Chinese medicine, there are six Yang (fu, "hollow") Organs and six Yin (zang, "solid") Organs. Each fu organ is paired with a Zang organ of the same element; the Fu organ embodies the Yang power, and each Zang organ the Yin power of that element. The Zang organs, being Yin, are considered more interior (though not necessarily according to their physical location in the body). Disharmonies of the Fu organs are more likely to be implicated in severe and chronic illnesses.