The Refutation of All Heresies (Greek: Φιλοσοφούμενα ή κατὰ πασῶν αἱρέσεων ἔλεγχος, Latin: Refutatio Omnium Haeresium), also called the Elenchus or Philosophumena, is a compendious Christian polemical work of the early third century, now generally attributed to Hippolytus of Rome. It catalogues both pagan beliefs and 33 gnostic Christian systems deemed heretical, making it a major source of information on contemporary opponents of Catholic orthodoxy.
The first book, a synopsis of Greek philosophy, circulated separately in several manuscripts and was known as the Philosophoumena (Greek: Φιλοσοφούμενα "philosophical teachings"), a title which some extend to the whole work. Books IV-X were recovered in 1842 in a manuscript at Mount Athos, while books II and III remain lost. The work was long attributed to the early Christian theologian Origen.
Hippolytus's work is divided into ten books, 8 of which have survived more or less intact. Books II and III, however, have not been unearthed, and their contents remain the subject of conjecture
Book I offers a summary of the thought of various ancient Greek philosophers. Catherine Osborne identifies Book I as being an important source of information on Pre-Socratic Philosophy. Hippolytus's most extensive treatment is given to the works of Pythagoras, Plato, and Aristotle. An outline of the philosophies of the Brahmins of India, Zamolxis of Thrace and the Celtic druids and also of the mythological poetry of Hesiod is given here.