archeus

noun

1. The vital principle or force believed by the Paracelsians to be responsible for alchemical reactions within living bodies, and hence for the growth and continuation of life.

   “[T]o acknovvledge any other Archeus, being inextricable difficulties along vvith it. For vvhere, ſay they, vvere all the Archei vvhich ſhap'd the VVaſps out of an Horſes Carcaſe? Are they parts of the Horſes Soul, or nevv intruding gueſts upon the old ones being ejected?”

   “Willis rejected not just scholasticism's ‘substantial forms’ but Paracelsus's ‘archeus’ doctrine as well.”

   “But Paracelsus' theory of the archeus and the alchemy of life inevitably led him into deeper waters.”