What is "vis medicatrix naturae"

n. The ability of the body to heal itself without intervention

Vis medicatrix naturae (literally "the healing power of nature", and also known as natura medica) is the Latin rendering of the Greek Νόσων φύσεις ἰητροί ("Nature is the physician(s) of diseases"), a phrase attributed to Hippocrates. While the phrase is not actually attested in his corpus, it nevertheless sums up one of the guiding principles of Hippocratic medicine, which is that organisms left alone can often heal themselves (cf. the Hippocratic primum non nocere).